June 10, 2025

Dear Fellow Shareholder:

We are sending this prospectus/information statement to you because you are a shareholder of Putnam Sustainable Retirement 2025 Fund. The Board of Trustees of Putnam Sustainable Retirement 2025 Fund is pleased to announce the upcoming merger of Putnam Sustainable Retirement 2025 Fund with and into Putnam Sustainable Retirement Maturity Fund. In this merger, shares of Putnam Sustainable Retirement 2025 Fund would, in effect, be exchanged for shares of Putnam Sustainable Retirement Maturity Fund with an equal total net asset value. The exchange is expected to be tax free for federal income tax purposes.

Putnam Sustainable Retirement 2025 Fund seeks capital appreciation and current income consistent with a decreasing emphasis on capital appreciation and an increasing emphasis on current income as it approaches its target date. Putnam Sustainable Retirement Maturity Fund seeks as high a rate of current income as Franklin Advisers, Inc. (the “Investment Manager”) believes is consistent with preservation of capital. As described in the Putnam Sustainable Retirement 2025 Fund prospectus, in 2025, the target date year for the Putnam Sustainable Retirement 2025 Fund, the fund’s target allocations will correspond to those of Putnam Sustainable Retirement Maturity Fund, and the Putnam Sustainable Retirement 2025 Fund will be merged into the Putnam Sustainable Retirement Maturity Fund. The Investment Manager believes that the merger is in the best interests of shareholders of Putnam Sustainable Retirement 2025 Fund and Putnam Sustainable Retirement Maturity Fund. Because the funds have the same portfolio managers, similar investment goals and investment strategies and because Putnam Sustainable Retirement 2025 Fund’s target allocations will correspond to those of Putnam Sustainable Retirement Maturity Fund before the merger, the Investment Manager believes the funds are appropriate merger partners.

The Trustees of your fund, Putnam Sustainable Retirement 2025 Fund, have carefully reviewed the terms of the merger and determined unanimously to approve the merger. We are not asking you for a proxy, and you are requested not to send a proxy. Details regarding the terms of the merger, and its potential benefits and costs to shareholders, are discussed in the prospectus/information statement, which we urge you to review carefully.

Sincerely yours,

Prospectus/Information Statement

June 10, 2025

Acquisition of the assets of

Putnam Sustainable Retirement 2025 Fund
100 Federal Street
Boston, Massachusetts 02110
1-617-292-1000

by and in exchange for shares of

Putnam Sustainable Retirement Maturity Fund
100 Federal Street
Boston, Massachusetts 02110
1-617-292-1000

Table of Contents

This prospectus/information statement relates to the merger of Putnam Sustainable Retirement 2025 Fund with and into Putnam Sustainable Retirement Maturity Fund. In the merger, each shareholder of Putnam Sustainable Retirement 2025 Fund will receive shares of the corresponding class of Putnam Sustainable Retirement Maturity Fund equal in aggregate value at the date of the exchange to the aggregate value of the shareholder’s Putnam Sustainable Retirement 2025 Fund shares.

The prospectus/information statement explains what you should know about the merger and investing in Putnam Sustainable Retirement Maturity Fund, an open-end, diversified registered management investment company. Please read this prospectus/information statement and keep it for future reference.

WE ARE NOT ASKING YOU FOR A PROXY AND YOU ARE REQUESTED NOT TO SEND US A PROXY

The statement of additional information relating to the merger, dated June 10, 2025 (the “Merger SAI”) and the other documents identified below are incorporated into this prospectus/information statement by reference. Shareholders may obtain free copies of any document incorporated by reference into this prospectus/information statement, request other information about the funds or make shareholder inquiries by contacting their financial professional, at franklintempleton.com, by calling Putnam toll-free at 1-800-225-1581, or by emailing Putnam at funddocuments@putnam.com. This information may also be obtained by contacting the Securities and Exchange Commission (the “SEC”), as described below.

The securities offered by this prospectus/information statement have not been approved or disapproved by the SEC, nor has the SEC passed upon the accuracy or adequacy of this prospectus/information statement. Any representation to the contrary is a criminal offense.

Shares of Putnam Sustainable Retirement Maturity Fund are not deposits or obligations of, or guaranteed or endorsed by, any financial institution, are not insured by the Federal Deposit Insurance Corporation, the Federal Reserve Board or any other agency, and involve risk, including the possible loss of principal amounts invested.

The following documents have been filed with the SEC and are incorporated into this prospectus/information statement by reference:

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Information regarding Putnam Sustainable Retirement Maturity Fund is included in this prospectus/information statement, including information regarding Putnam Sustainable Retirement Maturity Fund’s dividends and distributions, sales charges, and 12b-1 fees; investment advisor and portfolio manager; the pricing, purchase, sale, and redemption of Putnam Sustainable Retirement Maturity Fund shares; the tax treatment of distributions and tax consequences to shareholders of buying, holding, exchanging, and selling Putnam Sustainable Retirement Maturity Fund shares; Putnam Sustainable Retirement Maturity Fund’s financial highlights; and Putnam Sustainable Retirement Maturity Fund’s policy regarding frequent trading in Putnam Sustainable Retirement Maturity Fund shares.

This document will give you information about the merger. Much of the information is required under SEC rules; some of it is technical. If there is anything you do not understand, please contact us at our toll-free number, 1-800-225-1581, or call your financial professional. Like Putnam Sustainable Retirement 2025 Fund, Putnam Sustainable Retirement Maturity Fund is in the family of Putnam mutual funds. Putnam Sustainable Retirement Maturity Fund and Putnam Sustainable Retirement 2025 Fund are collectively referred to herein as the “funds,” and each is referred to individually as a “fund.”

Putnam Sustainable Retirement 2025 Fund and Putnam Sustainable Retirement Maturity Fund are subject to the informational requirements of the Securities Act of 1933, as amended, the Securities Exchange Act of 1934, as amended, and the Investment Company Act of 1940, as amended (the “1940 Act”), and, as a result, file reports and other information with the SEC. These reports and other information can be inspected and copied at the Public Reference Room maintained by the SEC. Copies may be obtained, after paying a duplicating fee, by electronic request at publicinfo@sec.gov, or by writing to the Public Reference Branch of the SEC Office of Consumer Affairs and Information Services, 100 F Street, N.E., Washington, D.C. 20549-0102. In addition, copies of these documents may be viewed online or downloaded from the SEC’s website at www.sec.gov.

I. Questions and Answers Regarding the Merger

The responses to the questions that follow provide an overview of key points typically of concern to shareholders regarding a mutual fund merger. These responses are qualified in their entirety by the remainder of the prospectus/information statement, which contains additional information and further details about the merger.

WE ARE NOT ASKING YOU FOR A PROXY AND YOU ARE REQUESTED NOT TO SEND US A PROXY

1. What is happening?

The Trustees of The Putnam Funds have approved the merger of Putnam Sustainable Retirement 2025 Fund into Putnam Sustainable Retirement Maturity Fund contemplated by the Agreement and Plan of Reorganization (described in Part III). Upon the closing of the merger, all of the assets of Putnam Sustainable Retirement 2025 Fund will be transferred to Putnam Sustainable Retirement Maturity Fund. In exchange, Putnam Sustainable Retirement Maturity Fund will issue and deliver shares of Putnam Sustainable Retirement Maturity Fund (the “Merger Shares”) to Putnam Sustainable Retirement 2025 Fund and will also assume all of the liabilities of Putnam Sustainable Retirement 2025 Fund. The Merger Shares will have an aggregate value equal to the value of Putnam Sustainable Retirement 2025 Fund’s assets net of liabilities. Immediately after it receives the Merger Shares, Putnam Sustainable Retirement 2025 Fund will distribute the Merger Shares to its shareholders, pro rata. Shareholders will receive Merger Shares of the same class as the Putnam Sustainable Retirement 2025 Fund shares they held. It is currently anticipated that the merger will close on or about July 28, 2025, with the net asset value of shares to be issued in the merger currently expected to be determined on or about July 25, 2025.

When adopting Rule 17a-8 under the 1940 Act, the SEC stated its view that approval by shareholders of a target fund would be required if the merger would result in a change that, in a context other than a merger, would require shareholder approval under the 1940 Act. These factors generally include increased distribution fees as a result of the merger, materially different advisory contracts, different Trustees or materially different fundamental investment policies as between the target and surviving funds.

Shareholder approval of this merger is not required because none of the factors requiring a shareholder vote are present.

2. What will happen to my shares of Putnam Sustainable Retirement 2025 Fund as a result of the merger?

Your shares of Putnam Sustainable Retirement 2025 Fund will, in effect, be exchanged for shares of Putnam Sustainable Retirement Maturity Fund of the same class and with an equal aggregate net asset value on the date of the merger.

3. Why did the Trustees approve the merger?

Franklin Advisers, Inc. (“Franklin Advisers” or the “Investment Manager”) has recommended the merger because it believes that it is in the best interests of shareholders of Putnam Sustainable Retirement 2025 Fund and Putnam Sustainable Retirement Maturity Fund. Putnam Sustainable Retirement 2025 Fund commenced operations on November 1, 2004 and had net assets of $370.57 million as of February 28, 2025. Putnam Sustainable Retirement Maturity Fund commenced operations on November 1, 2004 and had net assets of $215.35 million as of February 28, 2025. The Investment Manager has recommended the merger because, as described in Putnam Sustainable Retirement 2025 Fund’s prospectus, that fund was intended to merge into Putnam Sustainable Retirement Maturity Fund in 2025. The funds have the same portfolio managers, similar investment goals, and pursue the similar investment strategies. In addition, as the Putnam Sustainable Retirement 2025 Fund’s prospectus discloses, by the time of the merger, Putnam Sustainable Retirement 2025 Fund’s target allocations among asset classes and underlying funds will correspond to those of Putnam Sustainable Retirement Maturity Fund. As a result, the Investment Manager believes that the funds are appropriate merger partners.

The Trustees have determined that the merger is in the best interests of the shareholders of your fund.

4. How do the investment goals, strategies, policies and restrictions of the two funds compare?

Investment Goals and Strategies

The stated investment goals of the funds are similar and the funds pursue similar investment strategies. Putnam Sustainable Retirement 2025 Fund’s asset allocation strategy is intended to be attractive to investors who plan to retire or intend to begin making periodic withdrawals of their investments in or about 2025 (the target date). Putnam Sustainable Retirement 2025 Fund’s target allocations among asset classes and underlying funds have increasingly emphasized capital preservation and income over time and have changed gradually based on the number of remaining years until its target date. As disclosed in Putnam Sustainable Retirement 2025 Fund’s prospectus, in the target date year, Putnam Sustainable Retirement 2025 Fund’s target allocations among asset classes and underlying funds will correspond to those of the Putnam Sustainable Retirement Maturity Fund.

Putnam Sustainable Retirement Funds Glidepath

The Investment Manager expects that Putnam Sustainable Retirement 2025 Fund’s allocations among asset classes and underlying funds will correspond to those of Putnam Sustainable Retirement Maturity Fund at the time of the merger. While the table above shows the projected approximate allocations of Putnam Sustainable Retirement 2025 Fund and Putnam Sustainable Retirement Maturity Fund as of September 30, 2025, actual allocations as of that date may differ.

Investment Restrictions

The funds have identical fundamental investment restrictions.

5. How do the management fees and other expenses of the funds compare, and what are they estimated to be following the merger?

Putnam Sustainable Retirement 2025 Fund’s shareholders are expected to benefit overall in terms of a lower management fee as a result of the proposed merger.

Each fund pays a monthly management fee to the Investment Manager that is calculated by applying a rate to each fund’s average net assets for the month. For Putnam Sustainable Retirement 2025 Fund, the annual rate is based on the number of years remaining (determined as of September 30th of each year and applicable through September 30th of the following year) until the date references in the fund’s name. The current annual rate for Putnam Sustainable Retirement 2025 Fund is 0.47%. For Putnam Sustainable Retirement Maturity Fund, the annual rate is 0.46%. Following the merger, the Investment Manager expects the management fee rate of the Putnam Sustainable Retirement Maturity Fund to be 0.46%.

As of January 31, 2025, the total annual operating expenses of class A, C, R, R3, R4, R5, R6 and Y shares of Putnam Sustainable Retirement 2025 Fund, after expense reimbursement, were 0.85%, 1.60%, 1.25%, 1.00%, 0.75%, 0.60%, 0.50% and 0.60%, respectively. As of January 31, 2025, the total annual operating expenses of class A, C, R, R3, R4, R5, R6 and Y shares of Putnam Sustainable Retirement Maturity Fund, after expense reimbursement, were 0.85%, 1.60%, 1.25%, 1.00%, 0.75%, 0.60%, 0.50% and 0.60%, respectively. After the merger, Putnam Sustainable Retirement Maturity Fund is expected to pay 0.85%, 1.60%, 1.25%, 1.00%, 0.75%, 0.60%, 0.50% and 0.60% for class A, C, R, R3, R4, R5, R6 and Y shares, respectively, in total expenses. Under the expense limitation agreement, the Investment Manager contractually agreed to reimburse each Putnam Sustainable Retirement Fund’s “acquired fund fees and expenses” in full, which includes the management fees and all other fees and expenses borne indirectly by the Putnam Sustainable Retirement Fund through its investments in underlying funds. In addition, under the expense limitation agreement, the Investment Manager contractually agrees to a cap on each Putnam Sustainable Retirement Fund’s total annual operating expenses, and the Investment Manager will waive and/or reimburse the expenses of each Putnam Sustainable Retirement Fund to the extent necessary to limit the total annual operating expenses of each share class of each Putnam Sustainable Retirement Fund (excluding payments under the fund’s distribution plan, brokerage, interest, taxes, investment-related expenses (including borrowing costs, i.e., short selling and line of credit costs), acquired fund fees and extraordinary expenses) to a specified percentage.

For more detailed information about fees and expenses, please see “Information about the Merger—Fees and Expenses.”

6. How does the investment performance of the funds compare?

The performance information below gives some indication of the risks associated with investment in the fund by showing each fund’s performance year to year and over time. The bar chart does not reflect the impact of sales charges. If it did, performance would be lower. Please remember that past performance is not necessarily an indication of future results. Monthly performance figures for the fund are available at www.franklintempleton.com. Brett S. Goldstein, CFA; Adrian H. Chan, CFA; Thomas Nelson, CFA; Berkeley Belknap; and Jonathan M. Schreiber, CFA serve as the portfolio managers for both funds, and would continue to serve as portfolio managers of Putnam Sustainable Retirement Maturity Fund after the merger.

The chart shows year-to-year changes in the net asset value performance of each fund’s class A shares, before sales charges.

Putnam Sustainable Retirement 2025 Fund

Annual total returns for class A shares before sales charges

Best calendar quarter 12/31/23 8.18%

Worst calendar quarter 3/31/20 –7.74%

Average annual total returns after sales charges
For periods ended 12/31/24

Putnam Sustainable Retirement Maturity Fund

Annual total returns for class A shares before sales charges

Best calendar quarter 12/31/23 8.56%

Worst calendar quarter 3/31/20 -5.69%

Average annual total returns after sales charges
For periods ended 12/31/24

After-tax returns reflect the historical highest individual federal marginal income tax rates and do not reflect state and local taxes. Actual after-tax returns depend on an investor’s tax situation and may differ from those shown. After-tax returns are shown for class A shares only and will vary for other classes.

These after-tax returns do not apply if you hold your fund shares through a 401(k) plan, an individual retirement account (IRA), or another tax-advantaged arrangement.

Putnam Sustainable Retirement Maturity Fund will be the accounting and performance survivor following the Reorganization. As such, Putnam Sustainable Retirement Maturity Fund will continue to have the same performance history following the Reorganization as it had prior to the Reorganization.

7. Will my dividends be affected by the merger?

Putnam Sustainable Retirement 2025 Fund distributes any net investment income and any net realized capital gains annually. Putnam Sustainable Retirement Maturity Fund declares a dividend monthly based on the Investment Manager’s projections of its estimated net income and normally distributes any net investment income monthly and any net realized capital gains annually. After the merger, Putnam Sustainable Retirement Maturity Fund will continue to declare a dividend monthly based on the Investment Manager’s projections of its estimated net income and will distribute any net investment income monthly and any net realized capital gains annually.

Before consummating the merger, Putnam Sustainable Retirement 2025 Fund will, and Putnam Sustainable Retirement Maturity Fund may, declare a distribution to shareholders that, together with all previous distributions qualifying for the dividends-paid deduction, will have the effect of distributing to shareholders, all of its investment company taxable income, net tax-exempt income (if any), and net capital gains, including those realized on the disposition of portfolio securities, whether independent of or in connection with the merger, effected prior to the merger. These distributions will generally be taxable to shareholders.

8. What are the federal income tax consequences of the merger?

The merger is expected to be a tax-free reorganization for federal income tax purposes.

Certain other tax consequences are discussed below under “Information about the Merger—Federal Income Tax Consequences.”

9. Is there any difference in the procedures for purchasing, redeeming and exchanging shares of the two funds?

No. The procedures for purchasing and redeeming shares of each fund, and for exchanging shares of each fund for shares of other Putnam funds, are identical.

Both Putnam Sustainable Retirement 2025 Fund and Putnam Sustainable Retirement Maturity Fund are open-end funds and make a continuous public offering of their shares. Putnam Sustainable Retirement 2025 Fund and Putnam Sustainable Retirement Maturity Fund currently offer eight classes of shares.

Shares of both funds may be purchased by contacting a financial professional or by calling Putnam Investor Services at 1-800-225-158.

You can sell your shares back to the fund or exchange them for shares of another Putnam fund any day the New York Stock Exchange (NYSE) is open. Shares may be sold or exchanged by mail, by phone, or, for exchanges only, online at www.franklintempleton.com. Some restrictions may apply.

10. Will the number of shares I own change after the merger?

Yes, the number of shares you own will change, but the total value of the shares of Putnam Sustainable Retirement Maturity Fund you receive will equal the total value of the shares of Putnam Sustainable Retirement 2025 Fund that you hold at the time of the merger. Even though the net asset value per share of each fund is different, the total net asset value of your holdings at the time of the merger will not change as a result of the merger.

11. What are the costs associated with the merger?

The Investment Manager will bear the costs of the merger in light of the expense limitation arrangements in place for the funds. The costs associated with the merger are estimated to be $141,197. These costs, representing legal and accounting expenses, portfolio transfer taxes (if any), the costs of printing and mailing this prospectus/information statement, SEC filing fees, or other similar expenses incurred in connection with the consummation of the merger, will be allocated evenly between the two funds except that the SEC filing fees (estimated to be $361) will be allocated between the two funds pro rata based on fund assets. This is expected to result in an estimated $70,637 being allocated to Putnam Sustainable Retirement 2025 Fund and an estimated $70,560 being allocated to Putnam Sustainable Retirement Maturity Fund. Because both funds are expected to benefit from the merger based on several factors, the Investment Manager determined that the allocation described above is a fair and objective manner of allocating the merger expenses. However, as noted above, under the current expense limitation agreements with the funds, the Investment Manager will bear all of these costs.

Because each fund’s’ investment allocations will correspond to the other’s at the time of the merger, the Investment Manager currently does not anticipate any portfolio realignment or related transaction costs in connection with the merger.

II. Principal Risk Factors

What are the principal risks of Putnam Sustainable Retirement Maturity Fund, and how do they compare with those of Putnam Sustainable Retirement 2025 Fund?

The Investment Manager pursues each fund’s goal by allocating its assets among underlying funds. Putnam Sustainable Retirement 2025 Fund’s target allocations among asset classes and underlying funds has increasingly emphasized capital preservation and income over time and has changed gradually based on the number of remaining years until its target date. As disclosed in the funds’ prospectus, in the target date year, Putnam Sustainable Retirement 2025 Fund’s target allocations will correspond to those of Putnam Sustainable Retirement Maturity Fund. For Putnam Sustainable Retirement Maturity Fund, target allocations among asset classes and underlying funds are not expected to change over time. Because the funds have similar investment goals, pursue similar investment strategies and will have corresponding target allocations prior to the merger, the principal risks of an investment in Putnam Sustainable Retirement Maturity Fund are identical to the risks of an investment in Putnam Sustainable Retirement 2025 Fund.

The main risks that could adversely affect the value of Putnam Sustainable Retirement Maturity Fund’s shares and the total return on an investment in Putnam Retirement Sustainable Retirement Fund include:

It is important to understand that you can lose money by investing in the fund. Losses may occur near, at or after the target date. There is no guarantee that the fund will provide adequate income at and through an investor’s retirement.

The fund’s allocation of assets among asset classes and the underlying funds may hurt performance. An underlying fund may change its investment program or policies without the fund’s approval, which could require the fund to reduce or eliminate its allocation to the underlying fund at an unfavorable time.

The fund invests in underlying funds and indirectly bears expenses related to the underlying funds. However, the Investment Manager has contractually agreed to waive fees, reimburse expenses of, or reimburse the fund through at least November 30, 2027 in an amount equal to the fund’s acquired fund fees and expenses (e.g., the fees and expenses incurred by the fund as a result of its investments in the underlying funds). The Investment Manager also has contractually agreed to waive fees and/or reimburse expenses of each class of shares of the fund through at least November 30, 2027 in an amount sufficient to result in total annual fund operating expenses for class A, C, R, R3, R4, R5, R6 and Y shares of the fund (exclusive of payments under the fund’s distribution plans, brokerage, interest, taxes, investment- related expenses, acquired fund fees and expenses, and extraordinary expenses) that equal 0.60%, 0.60%, 0.75%, 0.75%, 0.75%, 0.60%, 0.50%, and 0.60%, respectively, of the fund’s average net assets.

Pending investment in underlying funds, the fund also expects to temporarily invest cash balances resulting from purchase activity by fund shareholders in Putnam Government Money Market Fund, a money market mutual fund sponsored the Investment Manager, or in cash or cash equivalents. In addition, the fund expects to invest a portion of its assets in Putnam Government Money Market Fund or in cash or cash equivalents in order to manage shareholder redemptions. Large positions in Putnam Government Money Market Fund or in cash or cash equivalents may dampen performance and may prevent the fund from achieving its goal. These practices may be subject to other risks, as described under Miscellaneous Investments, Investment Practices and Risks in the SAI.

The fund also bears the risks associated with the underlying funds identified below. The relative significance of these risks will vary over time based on the fund’s target allocations to the underlying funds and to equity and fixed-income asset classes, which may change from time to time as discussed above.

Investment Strategy -Related Risks of the Underlying Funds

Sustainability and ESG investing risk. Investing in underlying funds with an ESG or sustainability focus may result in the fund having exposure to underlying funds that invest in certain types of companies, issuers, industries or sectors that the market may not favor. In evaluating an investment opportunity for the underlying funds, Franklin Advisers, Putnam Investment Management, LLC (“Putnam Management”) or PanAgora Asset Management, Inc. (“PanAgora”) may make investment decisions without the availability of optimal ESG-related data (which may be even less available with securitized debt instruments) or based on information and data that is incomplete or inaccurate. Sustainability and ESG metrics are not uniformly defined, and applying such metrics involves subjective assessments.

Sustainability and ESG scorings and assessments of issuers can vary across third-party data providers and may change over time. Franklin Advisers, Putnam Management and PanAgora do not rely exclusively on third-party data providers in evaluating sustainability and ESG criteria for the underlying funds. ESG information from third-party data providers may be incomplete, inaccurate or unavailable, particularly with respect to companies in emerging market countries, which may adversely impact the investment process. In addition, the business practices, products or services of issuers in which an underlying fund invests may change over time. As a result of these possibilities, among others, an underlying fund may temporarily hold securities that are inconsistent with the underlying fund’s ESG or sustainability investment criteria. Regulatory changes or interpretations regarding the definitions and/or use of ESG and/or sustainability criteria could have a material adverse effect on the underlying fund’s ability to invest in accordance with its investment policies and/or achieve its investment objective. The underlying funds do not restrict investments based solely on “negative screens”, and the underlying fixed-income funds do not restrict their fixed-income investments to “green bonds” (e.g., U.S. dollar-denominated bonds designated as “green” by the Climate Bonds Initiative). For the underlying funds that pursue fixed-income investment strategies, because fixed-income investments generally represent a promise to pay principal and interest by an issuer, and not an ownership interest, and may involve complex structures, ESG- related investment considerations may have a more limited impact on risk and return (or may have an impact over a different investment time horizon) relative to other asset classes, and this may be particularly true for shorter-term investments. In addition, holders of fixed-income investments do not typically have voting rights, unlike holders of equity investments who have the right to vote on issuer proposals.

Market risk. The value of investments in the underlying funds’ portfolios may fall or fail to rise over extended periods of time for a variety of reasons, including general economic, political or financial market conditions, investor sentiment and market perceptions, government actions, geopolitical events or changes, outbreaks of infectious illnesses or other widespread public health issues (including epidemics and pandemics), and factors related to a specific issuer, geography, industry or sector. These and other factors may lead to increased volatility and reduced liquidity in the underlying funds’ portfolio holdings, may negatively impact the fund’s performance, and may exacerbate other risks to which the fund is subject.

Common stock risk.(For all underlying funds except Core Bond ETF, High Yield ETF and Ultra Short ETF) Common stock represents an ownership interest in a company. The value of a company’s stock may fall or fail to rise as a result of factors directly relating to that company, such as decisions made by its management or lower demand for the company’s products or services. A stock’s value may also fall because of factors affecting not just the company, but also other companies in the same industry or in a number of different industries, such as increases in production costs.

Growth investing risk. Growth stocks may be more susceptible to earnings disappointments, and the market may not favor growth-style investing.

Value investing risk. Value stocks may fail to rebound, and the market may not favor value-style investing. Companies whose stocks we believe are undervalued by the market may have experienced adverse business developments or may be subject to special risks that have caused their stocks to be out of favor.

Small and midsize companies risk. Stocks of small and midsize companies often trade in smaller volumes, and their prices may fluctuate more than stocks of larger companies. Stocks of these companies may therefore be more vulnerable to adverse developments than those of larger companies.

Industry or sector concentration risk. (For all underlying funds except Core Bond ETF, High Yield ETF and Ultra Short ETF) From time to time, an underlying fund may invest a significant portion of its assets in companies in one or more related industries or sectors, which would make the underlying fund more vulnerable to adverse developments affecting those industries or sectors.

Model and data risk. (For all underlying funds except Sustainable Leaders ETF, Sustainable Future ETF and High Yield ETF) If the quantitative models or data that are used in managing an underlying fund prove to be incorrect or incomplete, investment decisions made in reliance on the models or data may not produce the desired results, and the underlying fund may realize losses. Additionally, market movements are likely to change the risk levels and risk allocations of the underlying fund. Investments made based on quantitative models may perform differently from the market as a whole.

Foreign investment risk. (For all underlying funds except Ultra Short ETF, Sustainable Leaders ETF and Sustainable Future ETF) The value of international investments traded in foreign currencies may be adversely impacted by fluctuations in exchange rates. International investments, particularly investments in emerging markets, may carry risks associated with potentially less stable economies or governments (such as the risk of seizure by a foreign government, the imposition of currency or other restrictions, or high levels of inflation), and may be or become illiquid. There may be less publicly- available information, or less reliable publicly-available information, about foreign companies (including information related to companies’ ESG practices), particularly with respect to emerging market companies, than publicly-available information regarding U.S. companies. As a result, an underlying fund’s ability to evaluate a foreign company, including with respect to its ESG or sustainability practices, may be more limited than its ability to evaluate a U.S. company.

Geographic focus risk. (For PanAgora International Equity ETF and PanAgora Emerging Markets Equity ETF) From time to time, an underlying fund may invest a significant portion of its assets in companies in one or more related geographic regions, industries or sectors, such as European and Asian countries, which would make the fund more vulnerable to adverse developments affecting those geographic regions, industries or sectors, including political, economic, or other developments adversely impacting ESG or sustainable investing.

Fixed-income investments risk. (For Core Bond ETF, High Yield ETF and Ultra Short ETF) The risks associated with fixed-income investments include interest rate risk, which is the risk that the value of an underlying fund’s investments is likely to fall if interest rates rise. Fixed-income investments are also subject to credit risk, which is the risk that the issuer of a fixed-income investment may default on payment of interest or principal. Credit risk is generally greater for debt not backed by the full faith and credit of the U.S. government, and interest rate risk is generally greater for longer-term debt. Fixed- income investments may be more susceptible to downgrades or defaults during economic downturns or other periods of economic stress. Mortgage-backed investments, unlike traditional debt investments, are also subject to prepayment risk, which means that they may increase in value less than other bonds when interest rates decline and decline in value more than other bonds when interest rates rise. The underlying fund may have to invest the proceeds from prepaid investments, including mortgage-backed investments, in other investments with less attractive terms and yields. The underlying fund’s investments in mortgage- backed securities, and in certain other securities and derivatives, may be or become illiquid. The underlying fund’s investments in mortgage-backed securities may make the underlying fund’s net asset value more susceptible to economic, market, political and other developments affecting the residential and commercial real estate markets and the servicing of mortgage loans secured by real estate properties.

During periods of difficult economic conditions, delinquencies and losses on commercial mortgage-backed investments in particular generally increase, including as a result of the effects of those conditions on commercial real estate markets, the ability of commercial tenants to make loan payments, and the ability of a property to attract and retain commercial tenants.

One of the underlying funds, High Yield ETF, invests mostly in higher-yield, higher-risk debt investments that are rated below BBB or its equivalent at the time of purchase by any nationally recognized securities rating agency rating such investments, or in unrated investments that Franklin Advisers believes are of comparable quality. The underlying fund may invest up to 15% of the underlying fund’s total assets in debt investments rated below CCC or its equivalent, at the time of purchase, by each rating agency rating such investments, or in unrated investments that Franklin Advisers believes are of comparable quality. This includes investments in the lowest rating category of the rating agency. The underlying fund will not necessarily sell an investment if its rating is reduced after Franklin Advisers buys it. Investments rated below BBB or its equivalent are below-investment-grade in quality. This rating reflects a greater possibility that the issuers may be unable to make timely payments of interest and principal and thus default. If a default occurs, or is perceived as likely to occur, the value of the investment will usually be more volatile and is likely to fall. The value of a debt instrument may also be affected by changes in, or perceptions of, the financial condition of the issuer, borrower, counterparty, or other entity, or underlying collateral or assets, or changes in, or perceptions of, specific or general market, economic, industry, political, regulatory, geopolitical, environmental, public health, and other conditions. A default or expected default could also make it difficult for the underlying fund to sell the investment at a price approximating the value Franklin Advisers had previously placed on it. Lower-rated debt usually has a more limited market than higher-rated debt, which may at times make it difficult for the underlying fund to buy or sell certain debt instruments or to establish their fair values.

Derivatives risk. (For all underlying funds except PanAgora International Equity ETF, PanAgora Emerging Markets Equity ETF, Sustainable Leaders ETF and Sustainable Future ETF) An underlying fund’s use of derivatives may increase the risks of investing in the underlying fund by increasing investment exposure (which may be considered leverage) or, in the case of many over-the- counter instruments, because of the potential inability to terminate or sell derivatives positions and the potential failure of the other party to the instrument to meet its obligations. The risk of a party failing to meet its obligations may increase if the fund has significant investment exposure to that counterparty. The value of derivatives may move in unexpected ways due to unanticipated market movements, the use of leverage, imperfect correlation between the derivative instrument and the reference asset, or other factors, especially in unusual market conditions, and volatility in the value of derivatives could adversely impact the underlying fund’s returns, obligations and exposures. Derivatives are also subject to other risks, including liquidity risk (e.g., liquidity demands arising from the requirement to make payments to a derivative counterparty), operational risk (e.g., settlement issues or system failure), and legal risk (e.g., insufficient legal documentation or contract enforceability issues).Floating rate obligations risk.(For Core Bond ETF, High Yield ETF and Ultra Short ETF) To the extent an underlying fund holds floating rate loans, interest rate risk may be reduced but will not be eliminated. While floating rate loans are normally secured by specific collateral or assets of the issuer (so that holders of the loans, such as the underlying fund, will have a priority claim on those assets in the event of default or bankruptcy of the issuer), the value of collateral may be insufficient to meet the issuer’s obligations, and the underlying fund’s access to collateral may be limited by bankruptcy or other insolvency laws. The settlement period (the period between the execution of the trade and the delivery of cash to the purchaser) for floating rate loan transactions is typically longer than seven days, and it is possible that sale proceeds from floating rate loan transactions will not be available to meet redemption obligations.

Portfolio turnover rate risk. From time to time an underlying fund may engage in frequent trading. Funds with high turnover may be more likely to realize capital gains that must be distributed to shareholders as taxable income. High turnover may also cause a fund to pay more brokerage commissions and to incur other transaction costs (including imputed transaction costs), which may detract from performance. A fund’s portfolio turnover rate and the amount of brokerage commissions it pays and transaction costs it incurs will vary over time based on market conditions.

Management and operational risk. There is no guarantee that the investment techniques, analyses, or judgments that Franklin Advisers, Putnam Management or PanAgora, as applicable, applies in making investment decisions for the underlying funds will produce the intended outcome or that the investments they select for the underlying funds will perform as well as other securities that were not selected for the underlying funds. Franklin Advisers, Putnam Management, PanAgora, or the underlying funds’ other service providers, may experience disruptions or operating errors that could negatively impact the underlying funds.

Risks Related to Investing in ETFs

As ETFs, shares of the underlying funds are traded in the secondary market. Prior to trading in the secondary market, shares of the underlying funds are “created” at NAV by market makers, large investors and institutions (collectively, “authorized participants”) only in creation units. A creation transaction generally takes place when an authorized participant deposits into an underlying fund a designated portfolio of securities, assets or other positions (a “creation basket”), and an amount of cash (including any cash representing the value of substituted securities, assets or other positions), if any, in exchange for a specified number of creation units. Similarly, shares of an underlying fund can be redeemed only in creation units, generally for a designated portfolio of securities, assets or other positions held by the underlying fund and an amount of cash (including any portion of such securities for which cash may be substituted), if any.

Fluctuation of net asset value (“NAV”) and share price risk. Shares of the underlying funds may trade at a larger premium or discount to their NAV than shares of other ETFs. The NAV of an underlying fund will generally fluctuate with changes in the market value of the underlying fund’s holdings. Underlying fund shares can be bought and sold in the secondary market at market prices. Disruptions to creations and redemptions, the existence of extreme market volatility or potential lack of an active trading market for an underlying fund’s shares may result in the underlying fund’s shares trading significantly above (at a premium) or below (at a discount) to NAV or to the intraday value of the underlying fund’s holdings. In addition, in stressed market conditions or periods of market disruption or volatility, the market for shares of the underlying funds may become less liquid in response to deteriorating liquidity in the markets for the underlying funds’ portfolio holdings.

Authorized participant concentration risk. Only an authorized participant may engage in creation and redemption transactions directly with an underlying fund. Your fund is not an authorized participant and can only purchase and sell underlying fund shares in the secondary market at market prices or through an authorized participant. The underlying fund may have a limited number of financial institutions that act as authorized participants, none of which are obligated to engage in creation and/or redemption transactions. To the extent that those authorized participants do not engage in creation and redemption orders, there may be a significantly diminished trading market for underlying fund shares, or underlying fund shares may trade at a discount (or premium) to NAV and possibly face trading halts and/or de-listing.

Trading issues risk. The underlying funds have a limited public trading history. Sustainable Leaders ETF and Sustainable Future ETF began trading publicly in May 2021, while PanAgora International Equity ETF, PanAgora Emerging Markets Equity ETF, Core Bond ETF, High Yield ETF, and Ultra Short ETF began trading publicly in January 2023. There can be no assurance that an active trading market will develop or be maintained or that the market for underlying fund shares will operate as intended, which could lead to the underlying funds’ shares trading at wider spreads and larger premiums and discounts to NAV than other actively managed ETFs. As a result, it may cost the fund more to trade underlying fund shares than shares of other ETFs. There is no guarantee that the underlying fund will be able to attract market makers and authorized participants. Market makers and authorized participants are not obligated to make a market in the underlying fund’s shares or to submit purchase and redemption orders for creation units.

The market prices of an underlying fund’s shares are expected to fluctuate, in some cases materially, in response to changes in the underlying fund’s NAV, the intraday value of the underlying fund’s holdings and supply and demand for the underlying fund’s shares. Each underlying fund’s respective investment manager cannot predict whether an underlying fund’s shares will trade above, below or at their NAV or the intraday value of the underlying fund’s holdings. During periods when an underlying fund is trading below its NAV, the fund may incur significant losses if it sells its underlying fund shares.

The securities held by an underlying fund may be traded in markets that close at a different time than the exchange on which the underlying fund’s shares are listed. Liquidity in those securities may be reduced after the applicable closing times. Accordingly, during the time when the exchange is open but after the applicable market closing, fixing or settlement times, bid-ask spreads on the exchange and the corresponding premium or discount to the NAV of the underlying funds’ shares may widen.

Large shareholder risk. Each underlying fund may be an investment option for mutual funds that are managed by Franklin Resources, Inc. (“Franklin Templeton”) and its affiliates as “funds of funds.” Additionally, other investors from time to time may make substantial investments in an underlying fund, including affiliates of Franklin Templeton, through seed capital arrangements. Such shareholders may at times be considered to control an underlying fund. Dispositions of a large number of shares by these shareholders may adversely affect an underlying fund’s liquidity and net assets to the extent such transactions are executed directly with the underlying fund in the form of redemptions through an authorized participant, rather than executed in the secondary market. These redemptions may also force an underlying fund to sell securities, which may increase the underlying fund’s brokerage costs. In addition, underlying fund returns may be adversely affected if an underlying fund holds a portion of its assets in liquid, cash-like investments in connection with or in anticipation of shareholder redemptions. To the extent these large shareholders transact in shares of an underlying fund on the secondary market, such transactions may account for a large percentage of the trading volume on the exchange and may, therefore, have a material effect (upward or downward) on the market price of the underlying fund’s shares.

Cash transactions risk. Some of the underlying funds may effect creations and redemptions in cash or partially in cash. Therefore, an underlying fund may be required to sell portfolio securities, incur transaction costs, and subsequently recognize gains on such sales that the underlying fund might not have recognized if it were to distribute portfolio securities in-kind. As such, investments by a fund in an underlying fund’s shares may be less tax-efficient than an investment in an ETF that distributes portfolio securities entirely in-kind. An underlying fund may also incur transaction costs in connection with creations effected in cash (in whole or in part).

Semi-transparent ETF risk. (For Sustainable Leaders ETF and Sustainable Future ETF) Two of the underlying funds, Sustainable Leaders ETF and Sustainable Future ETF (the “Semi-Transparent ETFs”), are different from traditional ETFs, including the other underlying funds. Traditional ETFs disclose to the public what assets they hold each day. However, the Semi-Transparent ETFs do not. This may create additional risks for an investment in the Semi-Transparent ETFs, including that an investor may have to pay more money to trade the Semi-Transparent ETF’s shares in light of the fact that the Semi-Transparent ETF will provide less information to traders, who tend to charge more for trades when they have less information. The price an investor pays to buy or sell an ETF’s shares on an exchange may not match the value of the ETF’s portfolio, and these price differences may be greater for the Semi-Transparent ETFs compared to other ETFs because they provide less information to traders. These additional risks may be even greater in adverse or uncertain market conditions.

The differences between the Semi-Transparent ETFs and other ETFs may also have advantages. By keeping certain information about the Semi-Transparent ETFs secret, a Semi-Transparent ETF may face less risk that other traders can predict or copy its investment strategy. This may improve the Semi- Transparent ETF’s performance. If other traders are able to copy or predict the Semi-Transparent ETF’s investment strategy, however, this may hurt the Semi-Transparent ETF’s performance.

Tracking basket structure risk. (For Sustainable Leaders ETF and Sustainable Future ETF) The Semi-Transparent ETFs are actively managed ETFs that operate pursuant to an exemptive order from the Securities and Exchange Commission and do not publicly disclose their complete portfolio holdings each business day. Instead, each Semi-Transparent ETF publishes each business day on its website a “Tracking Basket,” which is designed to closely track the daily performance of the Semi-Transparent ETF but is not the Semi-Transparent ETF’s actual portfolio. The Tracking Basket is comprised of: (1) select recently disclosed portfolio holdings and/or select securities from the universe from which the Semi-Transparent ETF’s investments are selected (“Strategy Components”); (2) liquid ETFs that convey information about the types of instruments (that are not otherwise fully represented by the Strategy Components) in which the Semi-Transparent ETF invests; and (3) cash and cash equivalents.

A Semi-Transparent ETF’s Tracking Basket structure may affect the price at which shares of the Semi- Transparent ETF trade in the secondary market. Although the Tracking Basket is intended to provide investors with enough information to allow for an effective arbitrage mechanism that will keep the market price of each Semi-Transparent ETF at or close to its NAV per share, there is a risk that market prices will vary significantly from NAV. The Semi-Transparent ETFs, which trade on the basis of a published Tracking Basket, may trade at a wider bid/ask spread than ETFs that publish their portfolios on a daily basis, and therefore, may cost investors more to trade. These risks may increase during periods of market disruption or volatility. In addition, although each Semi-Transparent ETF seeks to benefit from keeping its portfolio information secret, market participants may attempt to use the Tracking Basket to identify the Semi- Transparent ETF’s trading strategy. If successful, this could result in such market participants engaging in certain predatory trading practices that may have the potential to harm the Semi-Transparent ETF and its shareholders, such as front running the Semi-Transparent ETF’s trades of portfolio securities.

Arbitrage risk. (For Sustainable Leaders ETF and Sustainable Future ETF) Unlike ETFs that publicly disclose their complete portfolio holdings each business day, each Semi-Transparent ETF provides certain other information intended to allow market participants to estimate the value of positions in the Semi-Transparent ETF’s shares. Although this information is designed to facilitate arbitrage opportunities in the Semi-Transparent ETF’s shares to reduce bid/ask spreads and minimize discounts or premiums between the market price and NAV of the Semi-Transparent ETF shares, there is no guarantee the Semi- Transparent ETF’s arbitrage mechanism will operate as intended and that the Semi-Transparent ETF will not experience wide bid/ask spreads and/or large discounts or premiums to NAV. In addition, market participants may attempt to use the disclosed information to “reverse engineer” the Semi-Transparent ETF’s trading strategy, which, if successful, could increase opportunities for predatory trading practices that may have the potential to negatively impact the Semi-Transparent ETF’s performance.

Trading halt risk. (For Sustainable Leaders ETF and Sustainable Future ETF) There may be circumstances where a security held in a Semi-Transparent ETF’s portfolio but not in the Tracking Basket does not have readily available market quotations. If Putnam Management determines that such circumstance may affect the reliability of the Tracking Basket as an arbitrage vehicle, that information, along with the identity and weighting of that security in the Semi-Transparent ETF’s portfolio, will be publicly disclosed on the Semi-Transparent ETF’s website, and Putnam Management will assess appropriate remedial measures. In these circumstances, market participants may use this information to engage in certain predatory trading practices that may have the potential to harm the Semi-Transparent ETF and its shareholders. In addition, if securities representing 10% or more of the Semi-Transparent ETF’s portfolio do not have readily available market quotations, Putnam Management would promptly request the exchange to halt trading of the Semi-Transparent ETF, meaning that investors (including the fund) would not be able to trade their shares. Trading may also be halted in other circumstances, for example, due to market conditions.

The fund may not achieve its goal, and it is not intended to be a complete investment program. An investment in the fund is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.

Investor Profile

Putnam Sustainable Retirement Maturity Fund is designed for investors in or near retirement or otherwise seeking an investment for use with a periodic withdrawal program. Investors are encouraged to seek the assistance of a financial professional in developing a periodic withdrawal program that is appropriate to their personal investment goals and financial circumstances. The fund also serves as the fund into which each of the Putnam Sustainable Retirement Funds, including the Putnam Sustainable Retirement 2025 Fund, will be merged in the target year of the Putnam Sustainable Retirement Fund. The fund makes no representations regarding its suitability for any particular investor or periodic withdrawal program.

Investors should understand that pursuing higher returns may involve higher volatility and that a fund’s performance results may not be sustainable.

What are the fund’s and each underlying fund’s main investment strategies and related risks?

The Investment Manager pursues the fund’s goal by investing primarily in underlying funds that focus on investments with positive sustainability or ESG characteristics. Under normal circumstances, the fund will invest in underlying funds (which, for purposes of this policy, include money market mutual funds advised by the Investment Manager or its affiliates) such that, in the aggregate, it has indirect exposure to investments that meet the Investment Manager’s, Putnam Management’s or PanAgora’s, as applicable, sustainability or ESG criteria and that represent at least 80% of the value of its net assets. The Investment Manager may not apply ESG or sustainability criteria to investments that are not subject to the fund’s 80% policy, and such investments may not meet the applicable ESG or sustainability criteria. Currently, the underlying funds are subject to the following risks:

Sustainability and ESG investing risk. Investing with a focus on companies or issuers that meet the Investment Manager’s, Putnam Management’s or PanAgora’s sustainability or ESG criteria or (for Sustainable Future ETF) a focus on Solutions Companies, whose products and services may provide solutions that directly impact sustainable environmental, social and economic development, may result in the underlying fund investing in certain types of companies, issuers, industries or sectors that the market may not favor. Conversely, investing in such companies or issuers may result in the underlying fund foregoing investment in securities that outperform the underlying fund’s investments in certain environments.

In evaluating an investment opportunity, the underlying fund’s manager may make investment decisions without the availability of optimal ESG-related data (which may be even less available with securitized debt instruments) or based on information and data that is incomplete or inaccurate. Sustainability and ESG metrics are not uniformly defined, and applying such metrics involves subjective assessments.

Sustainability and ESG scorings and assessments of issuers can vary across third-party data providers and may change over time. ESG information from third-party data providers may be incomplete, inaccurate or unavailable, particularly with respect to companies in emerging market countries, which may adversely impact the investment process. In addition, a company’s or issuer’s business practices, products or services may change over time. As a result of these possibilities, among others, the underlying fund may temporarily hold securities that are inconsistent with the underlying fund’s ESG investment criteria.

Regulatory changes or interpretations regarding the definitions and/or use of ESG or other sustainability criteria could have a material adverse effect on the underlying fund’s ability to invest in accordance with its investment policies and/or achieve its investment objective, as well as the ability of certain classes of investors to invest in funds, such as the underlying funds, whose strategies include ESG or other sustainability criteria. There may be limitations with respect to availability of ESG data in certain sectors, as well as limited availability of investments with positive ESG assessments in certain sectors. Franklin Advisers’, Putnam Management’s and PanAgora’s evaluation of sustainability and/or ESG criteria may change over time. Franklin Advisers, Putnam Management and PanAgora do not rely exclusively on third- party data providers in evaluating ESG criteria.

For Core Bond ETF, High Yield ETF and Ultra Short ETF. The underlying fund does not restrict its investments to “green bonds” (e.g., U.S. dollar-denominated bonds designated as “green” by the Climate Bonds Initiative) and does not restrict investments based solely on “negative screens”. Because fixed- income investments generally represent a promise to pay principal and interest by an issuer, and not an ownership interest, and may involve complex structures, ESG-related investment considerations may have a more limited impact on risk and return (or may have an impact over a different investment time horizon) relative to other asset classes, and this may be particularly true for shorter-term investments.

Third-party ESG data regarding fixed-income investments is generally less available than ESG data for equity investments. In addition, holders of fixed-income investments do not typically have voting rights, unlike holders of equity investments who have the right to vote on issuer proposals.

Market risk. The value of investments in an underlying fund’s portfolio may fall or fail to rise over extended periods of time for a variety of reasons, including general economic, political or financial market conditions; investor sentiment and market perceptions (including perceptions about monetary policy, interest rates, inflation or the risk of default); government actions (including protectionist measures, intervention in the financial markets or other regulation, and changes in fiscal, monetary or tax policies); geopolitical events or changes (including natural disasters, terrorism and war); outbreaks of infectious illnesses or other widespread public health issues (including epidemics and pandemics); and factors related to a specific issuer, geography, industry or sector. Foreign financial markets have their own market risks, and they may be more or less volatile than U.S. markets and may move in different directions.

During a general downturn in financial markets, multiple asset classes may decline in value simultaneously. These and other factors may lead to increased volatility and reduced liquidity in the underlying funds’ portfolio holdings. During those periods, an underlying fund may experience high levels of shareholder redemptions, and may have to sell securities at times when it would otherwise not do so, and at unfavorable prices. These risks may be exacerbated during economic downturns or other periods of economic stress. For Ultra Short ETF, the effects of inflation may erode the value of an investment in the underlying fund over time.

The COVID-19 pandemic and efforts to contain its spread have resulted in, among other effects, significant market volatility, exchange trading suspensions and closures, declines in global financial markets, higher default rates, significant changes in fiscal and monetary policies, and economic downturns and recessions. The effects of the COVID-19 pandemic have negatively affected, and may continue to negatively affect, the global economy, the economies of the United States and other individual countries, the financial performance of individual issuers, sectors, industries, asset classes, and markets, and the value, volatility, and liquidity of particular securities and other assets. The effects of the COVID-19 pandemic also are likely to exacerbate other risks that apply to an underlying fund, including the risks disclosed in this prospectus/information statement, which could negatively impact the underlying fund’s performance and lead to losses on your fund’s investment in the underlying fund. The duration of the COVID-19 pandemic and its effects cannot be determined with certainty.

Common stock risk. (For all underlying funds except Core Bond ETF, High Yield ETF and Ultra Short ETF) Common stock represents an ownership interest in a company. The value of a company’s stock may fall or fail to rise as a result of factors directly relating to that company, such as decisions made by its management or lower demand for the company’s products or services. A stock’s value may also fall because of factors affecting not just the company, but also other companies in the same industry or in a number of different industries, such as increases in production costs. The value of a company’s stock may also be affected by changes in financial markets that are relatively unrelated to the company or its industry, such as changes in interest rates, currency exchange rates, or inflation rates. In addition, a company’s stock generally pays dividends only after the company invests in its own business and makes required payments to holders of its bonds and other debt. For this reason, the value of a company’s stock will usually react more strongly than its bonds and other debt to actual or perceived changes in the company’s financial condition or prospects.

Growth investing risk. Stocks of companies that the underlying funds’ managers believe are fast-growing may trade at a higher multiple of current earnings than other stocks. The values of these stocks may be more sensitive to changes in current or expected earnings or to heightened levels of inflation than the values of other stocks. If the underlying funds’ managers’ assessment of the prospects for a company’s earnings growth is wrong, or if the underlying funds’ managers’ judgment of how other investors will value the company’s earnings growth is wrong, then the price of the company’s stock may fall or may not approach the value that the underlying funds’ managers have placed on it. In addition, growth stocks, at times, may not perform as well as value stocks or the stock market in general, and may be out of favor with investors for varying periods of time.

Value investing risk. Companies whose stocks the underlying funds’ managers believe are undervalued by the market may have experienced adverse business developments or may be subject to special risks that have caused their stocks to be out of favor. If the underlying funds’ managers’ assessment of a company’s prospects is wrong, or if other investors do not similarly recognize the value of the company, then the price of the company’s stock may fall or may not approach the value that the underlying funds’ managers have placed on it. In addition, value stocks, at times, may not perform as well as growth stocks or the stock market in general, and may be out of favor with investors for varying periods of time.

Small and midsize companies risk. These companies, some of which may have a market capitalization of less than $1 billion, are more likely than larger companies to have limited product lines, markets or financial resources, lack profitability, or depend on a small management group. Stocks of these companies often trade in smaller volumes, and their prices may fluctuate more than stocks of larger companies. Stocks of small and midsize companies may therefore be more vulnerable to adverse developments than those of larger companies. In addition, stocks of small and midsize companies, at times, may not perform as well as stocks of large companies or the stock market in general, and may be out of favor with investors for varying periods of time.

Industry or sector concentration risk. (For all underlying funds except Core Bond ETF, High Yield ETF and Ultra Short ETF) From time to time, the underlying fund may invest a significant portion of its assets in companies in one or more related industries or sectors, which would make the underlying fund more vulnerable to adverse developments affecting those industries or sectors.

Model and data risk. (For all underlying funds except Sustainable Leaders ETF, Sustainable Future ETF and High Yield ETF) The underlying fund’s managers use proprietary models and data supplied by third parties. They use models and data to, among other things, identify and assess trends and market opportunities and provide risk management insights. The underlying fund’s managers regularly enhance and update their models to reflect developing research, fundamental analysis, and access to new data. If the quantitative models or data used in managing the underlying fund prove to be incorrect or incomplete, investment decisions made in reliance on the models or data may not produce the desired results and may cause the underlying fund to underperform its benchmark or other funds with a similar investment goal, and the underlying fund may realize losses.

For example, the underlying fund’s managers may, in reliance on faulty models or data, be unsuccessful in its efforts to manage the underlying fund’s overall level of volatility and its efforts to diversify risk. Any hedging based on faulty models and data may prove to be unsuccessful. In addition, models may incorrectly forecast future behavior, leading to potential losses on a cash flow and/or mark-to-market basis. Use of these models in unforeseen or certain low-probability scenarios (often involving a market disruption of some kind) also may result in losses for the underlying fund.

All models require data. Some of the models that an underlying fund may use are typically constructed based on historical data, and the success of these models is dependent largely on the accuracy and reliability of the supplied historical data. If incorrect data is entered into a model, the resulting output will be incorrect.

As a result, any investment decisions made in reliance on the incorrect output from a model may not produce the desired results, and the underlying fund may realize losses. Even when data is correctly inputted into a model, the resulting information may differ, sometimes substantially, from other available data. For example, “model prices” that are provided by a model will often differ substantially from market prices, particularly for instruments that are complex in nature, such as derivatives. Models also rely on the proper functioning of hardware and technology, which are subject to disruption risk. There is no guarantee that the hardware and technology on which the models rely will be uninterrupted or error free, or that any defects in such hardware or technology will be able to be corrected in a short time period.

Foreign investment risk. (For all underlying funds except Sustainable Leaders ETF and Sustainable Future ETF)

For PanAgora International Equity ETF and PanAgora Emerging Markets Equity ETF. Foreign investments involve certain special risks, including:

The risks of foreign investments are typically increased in countries with less developed markets, which are sometimes referred to as emerging markets. Emerging markets may have less developed economies and legal and regulatory systems, and may be susceptible to greater political and economic instability than developed foreign markets. Countries with emerging markets are also more likely to experience high levels of inflation or currency devaluation, and investments in emerging markets may be more volatile and less liquid than investments in developed markets. For these and other reasons, investments in emerging markets are often considered speculative.

Certain risks related to foreign investments may also apply to some extent to U.S.-traded investments that are denominated in foreign currencies, investments in U.S. companies that are traded in foreign markets, or investments in U.S. companies that have significant foreign operations.

For Core Bond ETF, High Yield ETF and Ultra Short ETF. The underlying funds may invest in foreign investments, although foreign investments do not represent a primary focus of the underlying funds.

Foreign investments involve certain special risks. For example, their values may decline in response to changes in currency exchange rates, unfavorable political and legal developments, unreliable or untimely information, and economic and financial instability. In addition, the liquidity of these investments may be more limited than for most U.S. investments, which means the underlying fund may at times be unable to sell them at desirable prices. Foreign settlement procedures may also involve additional risks. These risks are generally greater in the case of developing (also known as emerging) markets, which typically have less developed legal and financial systems. There may be less publicly-available information, or less reliable publicly-available information, about foreign companies (including information related to companies’ ESG practices), particularly with respect to emerging market companies, than publicly- available information regarding U.S. companies. As a result, an underlying fund’s ability to evaluate a foreign company, including with respect to its ESG or sustainability practices, may be more limited than its ability to evaluate a U.S. company. Certain of these risks may also apply to some extent to U.S.-traded investments that are denominated in foreign currencies, investments in U.S. companies or issuers that are traded in foreign markets, or investments in U.S. companies or issuers that have significant foreign operations.

Geographic focus risk. (For PanAgora International Equity ETF and PanAgora Emerging Markets Equity ETF) From time to time, the underlying fund may invest a significant portion of its assets in companies located in a specific geographic region, such as common stocks of Asian or Pacific Basin countries, which would make the underlying fund more vulnerable to adverse developments affecting those geographic regions, including political, economic, or other developments adversely impacting ESG or sustainable investing. As a result, the underlying fund’s performance could be more volatile than the performance of more geographically diverse funds. Many Asian and Pacific Basin countries may be either developing (also known as emerging) or newly industrialized. These economies may be characterized by frequent currency fluctuations and restrictions, rising unemployment, rapid fluctuation in inflation and interest rates, reliance on exports and international trade, and less efficient markets. Furthermore, political and social unrest in some Asian and Pacific Basin countries could cause economic and market uncertainty in the region. For further information about risks of investing in Asian and Pacific Basin countries, see Risks of investing in the Asia Pacific Region in the SAI.

Interest rate risk. (For Core Bond ETF, High Yield ETF and Ultra Short ETF)

For Core Bond ETF and High Yield ETF. The values of bonds and other debt instruments usually rise and fall in response to changes in interest rates. Interest rates can change in response to the supply and demand for credit, government and/or central bank monetary policy and action, inflation rates, and other factors. Declining interest rates generally result in an increase in the value of existing debt instruments, and rising interest rates generally result in a decrease in the value of existing debt instruments. Changes in a debt instrument’s value usually will not affect the amount of interest income paid to an underlying fund, but will affect the value of the underlying fund’s shares. Interest rate risk is generally greater for investments with longer maturities. Some investments give the issuer the option to call or redeem an investment before its maturity date. If an issuer calls or redeems an investment during a time of declining interest rates, an underlying fund might have to reinvest the proceeds in an investment offering a lower yield, and, therefore, the underlying fund might not benefit from any increase in value as a result of declining interest rates.

For Ultra Short ETF. The values of money market and other fixed-income securities usually rise and fall in response to changes in interest rates. Interest rates can change in response to the supply and demand for credit, government and/or central bank monetary policy and action, inflation rates, and other factors.

Declining interest rates generally result in an increase in the value of existing fixed-income securities, and rising interest rates generally result in a decrease in the value of existing fixed-income securities.

Changes in a fixed-income security’s value usually will not affect the amount of income the underlying fund receives from them, but will affect the value of the underlying fund’s shares. Interest rate risk is generally greater for investments with longer maturities. Under normal circumstances, the dollar-weighted average portfolio maturity of the underlying fund is not expected to exceed four years. Short-term investments may have lower yields than longer-term investments. As mentioned in the underlying fund summary, under normal circumstances the effective duration of Ultra Short ETF’s portfolio will generally not be greater than one year. Effective duration provides a measure of an underlying fund’s interest-rate sensitivity. The longer an underlying fund’s duration, the more sensitive the underlying fund is to shifts in interest rates. As a general rule, a 1% rise in interest rates means a 1% fall in value for every year of duration. Some investments that the underlying fund purchases have an interest rate that changes based on a market interest rate and/or allow the holder to demand payment of principal and accrued interest before the scheduled maturity date. Franklin Advisers measures the maturity of these obligations using the relatively short period until the interest rate resets and/or payment could be demanded. Because the interest rate on these investments can change, these investments are unlikely to be able to lock in favorable longer-term interest rates.

Credit risk. (For Core Bond ETF, High Yield ETF and Ultra Short ETF) Investors normally expect to be compensated in proportion to the risk they are assuming. Thus, debt of issuers with poor credit prospects usually offers higher yields than debt of issuers with more secure credit. Higher-rated investments generally have lower credit risk. Core Bond ETF invests mainly in investment-grade investments. These are rated at least BBB or its equivalent at the time of purchase by a nationally recognized securities rating agency, or are unrated investments that Franklin Advisers believes are of comparable quality. The underlying fund may also invest in securities rated below investment grade. However, the underlying fund will not invest in securities that are rated lower than B or its equivalent by each rating agency rating the investment, or in unrated securities that Franklin Advisers believes are of comparable quality.

Ultra Short ETF invests in investment-grade investments. These are rated at least BBB or its equivalent at the time of purchase by a nationally recognized securities rating agency, or are unrated investments that Franklin Advisers believes are of comparable quality. This means the underlying fund may at times hold securities rated below-investment-grade (sometimes referred to as “junk bonds”) if the rating for a security held by the underlying fund is reduced to below-investment-grade.

High Yield ETF invests mostly in higher-yield, higher-risk debt investments that are rated below BBB or its equivalent at the time of purchase by any nationally recognized securities rating agency rating such investments, or in unrated investments that Franklin Advisers believes are of comparable quality. The underlying fund may invest up to 15% of the underlying fund’s total assets in debt investments rated below CCC or its equivalent, at the time of purchase, by each rating agency rating such investments, or in unrated investments that Franklin Advisers believes are of comparable quality. This includes investments in the lowest rating category of the rating agency. The underlying fund will not necessarily sell an investment if its rating is reduced after Franklin Advisers buys it. Investments rated below BBB or its equivalent are below-investment-grade in quality. This rating reflects a greater possibility that the issuers may be unable to make timely payments of interest and principal and thus default. If a default occurs, or is perceived as likely to occur, the value of the investment will usually be more volatile and could decrease. The value of a debt instrument may also be affected by changes in, or perceptions of, the financial condition of the issuer, borrower, counterparty, or other entity, or underlying collateral or assets, or changes in, or perceptions of, specific or general market, economic, industry, political, regulatory, geopolitical, environmental, public health, and other conditions. A default or expected default could also make it difficult for the underlying fund to sell the investment at a price approximating the value Franklin Advisers had previously placed on it. Lower-rated debt usually has a more limited market than higher- rated debt, which may at times make it difficult for the underlying fund to buy or sell certain debt instruments or to establish their fair values.

Each of Core Bond ETF, High Yield ETF and Ultra Short ETF will not necessarily sell an investment if its rating is reduced after Franklin Advisers buys it. Investments rated below BBB or its equivalent are below- investment-grade in quality (sometimes referred to as “junk bonds”) and may be considered speculative. This rating reflects a greater possibility that the issuers may be unable to make timely payments of interest and principal and thus default. If a default occurs, or is perceived as likely to occur, the value of the investment will usually be more volatile and likely to fall. The value of a debt instrument may also be affected by changes in, or perceptions of, the financial condition of the issuer, borrower, counterparty, or other entity, or underlying collateral or assets, or changes in, or perceptions of, specific or general market, economic, industry, political, regulatory, geopolitical, environmental, public health, and other conditions. A default or expected default could also make it difficult for the underlying fund to sell the investment at a price approximating the value Franklin Advisers had previously placed on it. Lower-rated debt usually has a more limited market than higher-rated debt, which may at times make it difficult for the underlying fund to buy or sell certain debt instruments or to establish their fair values. Credit risk is generally greater for zero-coupon bonds and other investments that are issued at less than their face value and that are required to make interest payments only at maturity rather than at intervals during the life of the investment.

Bond investments may be more susceptible to downgrades or defaults during economic downturns or other periods of economic stress, which can significantly strain the financial resources of debt issuers, including the issuers of the bonds in which the underlying fund invests (or has exposure to). This may make it less likely that those issuers can meet their financial obligations when due and may adversely impact the value of their bonds, which could negatively impact the performance of the underlying fund. It is difficult to predict the level of financial stress and duration of such stress issuers may experience.

Credit ratings are based largely on the issuer’s historical financial condition and the rating agencies’ investment analysis at the time of rating. The rating assigned to any particular investment does not necessarily reflect the issuer’s current financial condition, and does not reflect an assessment of the investment’s volatility or liquidity. Although Franklin Advisers considers credit ratings in making investment decisions, it performs its own investment analysis and does not rely only on ratings assigned by the rating agencies. Franklin Advisers’ success in achieving the underlying fund’s goal may depend more on its own credit analysis when the underlying fund buys lower-rated debt than when the underlying fund buys investment-grade debt. The underlying fund may have to participate in legal proceedings involving the issuer. This could increase the underlying fund’s operating expenses and decrease its net asset value.

Although investment-grade investments generally have lower credit risk, they may share some of the risks of lower-rated investments. U.S. government investments generally have the least credit risk, but are not completely free of credit risk. While some investments, such as U.S. Treasury obligations and Ginnie Mae certificates, are backed by the full faith and credit of the U.S. government, others are backed only by the credit of the issuer. Mortgage-backed securities may be subject to the risk that underlying borrowers will be unable to meet their obligations.

Prepayment risk. (For Core Bond ETF and Ultra Short ETF) Traditional debt investments typically pay a fixed rate of interest until maturity, when the entire principal amount is due. In contrast, payments on securitized debt instruments, including mortgage-backed and asset-backed investments, typically include both interest and partial payment of principal. Principal may also be prepaid voluntarily or as a result of refinancing or foreclosure. The underlying funds may have to invest the proceeds from prepaid investments in other investments with less attractive terms and yields.

Compared to debt that cannot be prepaid, mortgage-backed investments are less likely to increase in value during periods of declining interest rates and have a higher risk of decline in value during periods of rising interest rates. These investments may increase the volatility of an underlying fund. Some mortgage- backed investments receive only the interest portion or the principal portion of payments on the underlying mortgages. The yields and values of these investments are extremely sensitive to changes in interest rates and in the rate of principal payments on the underlying mortgages. The market for these investments may be volatile and limited, which may make them difficult to buy or sell. Asset-backed securities are structured like mortgage-backed securities, but instead of mortgage loans or interests in mortgage loans, the underlying assets may include such items as motor vehicle installment sales or installment loan contracts, leases of various types of real and personal property and receivables from credit card agreements. Asset-backed securities are subject to risks similar to those of mortgage-backed securities.

Derivatives risk. (For all underlying funds except Sustainable Leaders ETF and Sustainable Future ETF) An underlying fund may engage in a variety of transactions involving derivatives, such as futures, certain foreign currency transactions, options, warrants, credit default, total return and interest rate swap contracts and to-be-announced (TBA) commitments. Derivatives are financial instruments whose value depends upon, or is derived from, the value of something else, such as one or more underlying investments, pools of investments, indexes or currencies. The underlying funds may make use of “short” derivative positions, the values of which typically move in the opposite direction from the price of the underlying investment, pool of investments, index or currency. The underlying funds may use derivatives both for hedging and investment purposes. For example, an underlying fund manager may use derivatives to increase or decrease an underlying fund’s exposure to long or short-term interest rates (in the United States or abroad), to adjust the term of the fund’s U.S. Treasury security exposure, to adjust the fund’s positioning on the yield curve (a line that plots interest rates of bonds having equal credit quality but differing maturity dates) or to take tactical positions along the yield curve or to a particular currency or group of currencies, or as a substitute for a direct investment in the securities of one or more issuers.

However, an underlying fund’s manager may also choose not to use derivatives based on an evaluation of market conditions or the availability of suitable derivatives. Investments in derivatives may be applied toward meeting a requirement to invest in a particular kind of investment if the derivatives have economic characteristics similar to that investment.

Derivatives involve special risks and may result in losses. The successful use of derivatives depends on an underlying fund manager’s ability to manage these sophisticated instruments. Some derivatives are “leveraged,” which means they provide an underlying fund with investment exposure greater than the value of an underlying fund’s investment in the derivatives. As a result, these derivatives may magnify or otherwise increase investment losses to an underlying fund. The risk of loss from certain short derivative positions is theoretically unlimited. The value of derivatives may move in unexpected ways due to unanticipated market movements, the use of leverage, imperfect correlation between the derivative instrument and the reference asset, or other factors, especially in unusual market conditions, and volatility in the value of derivatives could adversely affect the fund’s returns, obligations and exposures.

Other risks arise from the potential inability to terminate or sell derivative positions. Derivatives may subject the fund to liquidity risk due to the obligation to make payments of margin, collateral, or settlement payments to counterparties. A liquid secondary market may not always exist for an underlying fund’s derivative positions. In fact, certain over-the-counter instruments (investments not traded on an exchange) may not be liquid. Over-the-counter instruments also involve the risk that the other party to the derivative transaction may not be willing or able to meet its obligations with respect to the derivative transaction. The risk of a party failing to meet its obligations may increase if the underlying fund has significant exposure to that counterparty. Derivative transactions may also be subject to operational risk, including due to documentation and settlement issues, system failures, inadequate controls and human error, and legal risk due to insufficient documentation, insufficient capacity or authority of a counterparty, or issues with respect to the legality or enforceability of the derivative contract. For further information about additional types and risks of derivatives, see Miscellaneous Investments, Investment Practices and Risks in the SAI.

For PanAgora International Equity and Emerging Markets Equity ETFs, derivatives are not a primary focus. PanAgora may use foreign currency transactions to increase or decrease the underlying fund’s exposure to a particular currency or group of currencies and may also use derivatives as a substitute for a direct investment in the securities of one or more issuers.

Floating rate obligations risk. (For Core Bond ETF, High Yield ETF and Ultra Short ETF)

The underlying fund may purchase taxable floating rate notes for short-term cash management or other investment purposes. Floating rate notes are debt instruments that provide for periodic adjustments in the interest rate. The interest rate on these instruments may be reset daily, weekly or on some other reset period and may have a floor or ceiling on interest rate changes. The interest rate of a floating rate instrument may be based on a known lending rate, such as the Secured Overnight Financing Rate, and is reset whenever such rate is adjusted. Interest rate adjustments are designed to help stabilize the instrument’s price or maintain a fixed spread to a predetermined benchmark. While this feature may protect against a decline in the instrument’s market price when interest rates or benchmark rates rise, it lowers the underlying fund’s income when interest rates or benchmark rates fall. The underlying fund’s income from its floating rate investments also may increase if interest rates rise. Floating rate obligations are less effective than fixed rate instruments at locking in a particular yield. Nevertheless, such obligations may fluctuate in value in response to interest rate changes if there is a delay between changes in market interest rates and the interest reset date for the obligation, or for other reasons. The underlying fund’s ability to receive payments of principal and interest and other amounts in connection with loans held by it will depend primarily on the financial condition of the issuer. The failure by the underlying fund to receive scheduled interest or principal payments on a loan would adversely affect the income of the underlying fund and would likely reduce the value of its assets, which would be reflected in a reduction in the underlying fund’s NAV. While most floating rate loans are below-investment-grade in quality, many also are senior in rank in the event of bankruptcy to most other securities of the borrower, such as common stock or public bonds. Floating rate loans are also normally secured by specific collateral or assets of the borrower so that the holders of the loans will have a priority claim on those assets in the event of default or bankruptcy of the issuer.

Floating rate notes and bonds may have a stated maturity in excess of one year, but may have features that permit a holder to demand payment of principal plus accrued interest upon a specified number of days’ notice. Frequently, such obligations are secured by letters of credit or other credit support arrangements provided by banks. If these obligations are not secured by letters of credit or other credit support arrangements, the underlying fund’s right to demand payment will be dependent on the ability of the issuer to pay principal and interest on demand. In addition, these obligations frequently are not rated by credit rating agencies and may involve heightened risk of default by the issuer. The issuer of such obligations normally has a corresponding right, after a given period, to prepay in its discretion the outstanding principal of the obligation plus accrued interest upon a specific number of days’ notice to the holders. If a loan is prepaid, the fund might have to reinvest the proceeds in an investment that may have lower yields than the yield on the prepaid loan or might not be able to take advantage of potential gains from increases in the credit quality of the issuer. There is no assurance that the underlying fund will be able to reinvest the proceeds of any prepayment at the same interest rate or on the same terms as those of the original instrument. The value of collateral, if any, securing a floating rate loan can decline, and may be insufficient to meet the borrower’s obligations or difficult to liquidate. In addition, the underlying fund’s access to collateral may be limited by bankruptcy or other insolvency proceedings. Floating rate loans may not be fully collateralized and may decline in value. Loans may not be considered “securities,” and it is possible that the underlying fund may not be entitled to rely on anti-fraud and other protections under the federal securities laws when it purchases loans. The absence of an active secondary market for floating rate notes could make it difficult for the underlying fund to dispose of the instruments, and the underlying fund could suffer a loss if the issuer defaults or during periods in which the underlying fund is not entitled to exercise its demand rights. When a reliable trading market for the floating rate instruments held by the underlying fund does not exist and the underlying fund may not demand payment of the principal amount of such instruments within seven days, the instruments may be deemed illiquid and therefore subject to the underlying fund’s limitation on investments in illiquid securities.

Although the market for the types of floating rate loans in which the underlying fund invests has become increasingly liquid over time, this market is still developing, and there can be no assurance that adverse developments with respect to this market or particular borrowers will not prevent the underlying fund from selling these loans at their market values when the underlying fund’s manager considers such a sale desirable. In addition, the settlement period (the period between the execution of the trade and the delivery of cash to the purchaser) for floating rate loan transactions may be significantly longer than the settlement period for other investments, and in some cases longer than seven days. Requirements to obtain consent of borrower and/or agent can delay or impede the underlying fund’s ability to sell the floating rate loans and can adversely affect the price that can be obtained. It is possible that sale proceeds from floating rate loan transactions will not be available to meet redemption obligations.

Management and operational risk. The underlying funds are actively managed and their performance will reflect, in part, their manager’s ability to make investment decisions that seek to achieve the underlying fund’s investment objective. There is no guarantee that the investment techniques, analyses, or judgments that the underlying funds’ managers apply in making investment decisions for will produce the intended outcome or that the investments the underlying manager selects for an underlying fund will perform as well as other securities that were not selected for that underlying fund. As a result, the underlying funds may underperform their benchmark or other funds with a similar investment goal and may realize losses. In addition, the underlying funds’ managers, or the underlying funds’ other service providers, may experience disruptions or operating errors that could negatively impact the underlying funds. Although service providers may have operational risk management policies and procedures and take appropriate precautions to avoid and mitigate risks that could lead to disruptions and operating errors, it may not be possible to identify all of the operational risks that may affect the underlying funds or to develop processes and controls to completely eliminate or mitigate their occurrence or effects.

Risks Related to Investing in ETFs

Fluctuation of NAV and share price risk. Shares may trade at a larger premium or discount to the NAV than shares of other ETFs. The NAV of the underlying fund’s shares will generally fluctuate with changes in the market value of the underlying fund’s holdings. The underlying fund’s shares are listed on an exchange and can be bought and sold in the secondary market at market prices. The market prices of shares will fluctuate in accordance with changes in NAV and supply and demand on the listing exchange. Although the arbitrage process, or for Sustainable Leaders ETF and Sustainable Future ETF, disclosure of the Tracking Basket and Tracking Basket Weight Overlap, is designed to permit the shares of the underlying fund to trade at market prices that are at or close to NAV, it is possible that the market price and NAV will vary significantly. As a result, you may sustain losses if you pay more than the shares’ NAV when you purchase shares or receive less than the shares’ NAV when you sell shares, in the secondary market. During periods of disruptions to creations and redemptions, the existence of extreme market volatility, or lack of an active trading market for the underlying fund’s shares, the market price of the fund’s shares is more likely to differ significantly from the underlying fund’s NAV or the intraday value of the underlying fund’s holdings. During such periods, you may be unable to sell your shares or may incur significant losses if you sell your shares. There are various methods by which investors can purchase and sell shares and various orders that may be placed. Investors should consult their financial intermediary before purchasing or selling shares of the underlying fund. Disruptions at market makers, authorized participants or market participants may also result in significant differences between the market price of the underlying fund’s shares and the underlying fund’s NAV. In addition, in stressed market conditions or periods of market disruption or volatility, the market for the fund’s shares may become less liquid in response to deteriorating liquidity in the markets for the underlying fund’s portfolio holdings.

The market price of the fund’s shares during the trading day, like the price of any exchange-traded security, includes a “bid/ask” spread charged by the exchange specialist, market makers, or other participants that trade the particular security. In times of severe market disruption or volatility, the bid/ask spread can increase significantly. At those times, the fund’s shares are most likely to be traded at a discount to NAV, and the discount is likely to be greatest when the price of shares is falling fastest, which may be the time that you most want to sell your shares.

Authorized participant concentration risk. Only authorized participants may engage in creation and redemption transactions directly with an underlying fund. Your fund is not an authorized participant and can only purchase and sell underlying fund shares in the secondary market at market prices or through an authorized participant. The underlying funds may have a limited number of financial institutions that act as authorized participants, none of which are obligated to engage in creation and/or redemption transactions. Decisions by market makers or authorized participants to reduce their role with respect to market making or creation and redemption activities during times of market stress, or a decline in the number of authorized participants due to decisions to exit the business, bankruptcy, or other factors, could inhibit the effectiveness of the arbitrage process in maintaining the relationship between the underlying value of an underlying fund’s portfolio securities and the market price of its shares. To the extent no other authorized participants are able to step forward to create or redeem, shares may trade at a discount (or premium) to NAV and possibly face delisting.

For Sustainable Leaders ETF and Sustainable Future ETF. The authorized participant concentration risk may be heightened due to the fact that the underlying fund has a novel and unique structure and does not disclose its portfolio holdings daily, unlike certain other actively managed ETFs, and could be greater during market disruptions or periods of market volatility and in scenarios where authorized participants have limited or diminished access to the capital required to post collateral.

Trading issues risk. The underlying funds have a limited public trading history. Sustainable Leaders ETF and Sustainable Future ETF began trading publicly in May 2021, while PanAgora International Equity ETF, PanAgora Emerging Markets Equity ETF, Core Bond ETF, High Yield ETF, and Ultra Short ETF began trading publicly in January 2023. Sustainable Leaders ETF and Sustainable Future ETF will operate differently from other actively managed ETFs that publish their portfolio holdings on a daily basis. For all of the underlying funds, although shares are listed on an exchange, there can be no assurance that an active trading market or requirements to remain listed will be met or maintained, or that the market for underlying fund shares will operate as intended. If the market does not operate as intended, it could lead to the underlying fund’s shares trading at wider spreads and larger premiums and discounts to NAV than other actively managed ETFs that publish their portfolio holdings on a daily basis, particularly during periods of market disruption or volatility. As a result, it may cost your fund more to trade underlying fund shares than shares of other ETFs.

Only an authorized participant may engage in creation or redemption transactions directly with the underlying fund. There is no guarantee that the underlying fund will be able to attract market makers and authorized participants. There are no obligations of market makers to make a market in the underlying fund’s shares or of authorized participants to submit purchase or redemption orders for creation units.

The market prices of the underlying fund’s shares are expected to fluctuate, in some cases materially, in response to changes in the underlying fund’s NAV, the intraday value of the underlying fund’s holdings and supply and demand for the underlying fund’s shares. The underlying fund’s manager cannot predict whether the underlying fund’s shares will trade above, below or at their NAV or the intraday value of the underlying fund’s holdings. During such periods, your fund may incur significant losses if it sells its shares. The securities held by the underlying fund may be traded in markets that close at a different time than the exchange on which the underlying fund’s shares are listed. Liquidity in those securities may be reduced after the applicable closing times. Accordingly, during the time when the exchange is open but after the applicable market closing, fixing or settlement times, bid-ask spreads on the exchange and the corresponding premium or discount to the shares’ NAV may widen.

In addition, trading of shares in the secondary market may be halted, for example, due to activation of market-wide “circuit breakers.” If trading halts or an unanticipated early closing of the listing exchange occurs, a shareholder may be unable to purchase or sell shares of the underlying fund.

If the underlying fund’s shares are delisted from the listing exchange, the underlying fund’s manager may seek to list the underlying fund shares on another market, merge the underlying fund with another exchange-traded fund or traditional mutual fund, or redeem the underlying fund shares at NAV.

Shares of the underlying fund, similar to shares of other issuers listed on a stock exchange, may be sold short and are therefore subject to the risk of increased volatility and price decreases associated with being sold short.

Large shareholder risk. Each underlying fund may be an investment option for mutual funds that are managed by Franklin Templeton and its affiliates as “funds of funds.” Additionally, other investors from time to time may make substantial investments in an underlying fund, including affiliates of Franklin Templeton, through seed capital arrangements. Such shareholders may at times be considered to control an underlying fund. Dispositions of a large number of shares by these shareholders may adversely affect an underlying fund’s liquidity and net assets to the extent such transactions are executed directly with the underlying fund in the form of redemptions through an authorized participant, rather than executed in the secondary market. These redemptions may also force an underlying fund to sell securities, which may increase the underlying fund’s brokerage costs. In addition, underlying fund returns may be adversely affected if an underlying fund holds a portion of its assets in liquid, cash-like investments in connection with or in anticipation of shareholder redemptions. To the extent these large shareholders transact in shares of an underlying fund on the secondary market, such transactions may account for a large percentage of the trading volume on the exchange and may, therefore, have a material effect (upward or downward) on the market price of the underlying fund’s shares.

Cash transactions risk. Some of the underlying funds may effect creations and redemptions in cash or partially in cash. Therefore, an underlying fund may be required to sell portfolio securities, incur transaction costs, and subsequently recognize gains on such sales that the underlying fund might not have recognized if it were to distribute portfolio securities in-kind. As such, investments by a fund in an underlying fund’s shares may be less tax-efficient than an investment in an ETF that distributes portfolio securities entirely in-kind. An underlying fund may also incur transaction costs in connection with creations effected in cash (in whole or in part).

Semi-transparent ETF risk. (For Sustainable Leaders ETF and Sustainable Future ETF) The Semi-Transparent ETFs, are different from traditional ETFs, including the other underlying funds. Traditional ETFs disclose to the public what assets they hold each day. However, the Semi-Transparent ETFs do not. This may create additional risks for an investment in the Semi-Transparent ETFs, including that an investor may have to pay more money to trade the Semi-Transparent ETF’s shares in light of the fact that the Semi-Transparent ETF will provide less information to traders, who tend to charge more for trades when they have less information. The price an investor pays to buy or sell an ETF’s shares on an exchange may not match the value of the ETF’s portfolio, and these price differences may be greater for the Semi-Transparent ETFs compared to other ETFs because they provide less information to traders.

These additional risks may be even greater in adverse or uncertain market conditions.

The differences between the Semi-Transparent ETFs and other ETFs may also have advantages. By keeping certain information about the Semi-Transparent ETFs secret, a Semi-Transparent ETF may face less risk that other traders can predict or copy its investment strategy. This may improve the Semi- Transparent ETF’s performance. If other traders are able to copy or predict the Semi-Transparent ETF’s investment strategy, however, this may hurt the Semi-Transparent ETF’s performance.

Tracking basket structure risk. (For Sustainable Leaders ETF and Sustainable Future ETF) The underlying fund’s Tracking Basket structure may affect the price at which shares of the underlying fund trade in the secondary market. Although the Tracking Basket is intended to provide investors with enough information to allow for an effective arbitrage mechanism that will keep the market price of the underlying fund at or close to the NAV per share of the underlying fund, the Tracking Basket methodology is relatively new as an arbitrage mechanism and has not been proven in all market environments. There is a risk (which may increase during periods of market disruption or volatility) that market prices will vary significantly from the NAV of the underlying fund. ETFs trading on the basis of a published Tracking Basket may trade at a wider bid/ask spread than ETFs that publish their portfolios on a daily basis, especially during periods of market disruption or volatility, and therefore, may cost your fund more to trade. At certain thresholds for such premiums/discounts, bid/ask spreads and tracking error, the underlying fund’s Board of Trustees will consider possible remedial measures, which may include liquidation or conversion to a fully-transparent, active ETF or a mutual fund. While the Tracking Basket includes some of the underlying fund’s holdings, it is not the underlying fund’s actual portfolio. The underlying fund will not disclose its actual portfolio daily and will not require a minimum overlap of holdings between the Tracking Basket and the underlying fund’s actual portfolio. In addition, although the underlying fund seeks to benefit from keeping its portfolio information secret, market participants may attempt to use the Tracking Basket to identify the underlying fund’s trading strategy. If successful, this could result in such market participants engaging in certain predatory trading practices that may have the potential to harm the underlying fund and its shareholders, such as front running the underlying fund’s trades of portfolio securities.

Arbitrage risk. (For Sustainable Leaders ETF and Sustainable Future ETF) Unlike ETFs that publicly disclose their complete portfolio holdings each business day, the underlying fund discloses the Tracking Basket and Tracking Basket Weight Overlap, which is intended to allow market participants to estimate the value of positions in underlying fund shares. Although this information is designed to facilitate arbitrage opportunities in underlying fund shares to reduce bid/ask spreads and minimize discounts or premiums between the market price and NAV of underlying fund shares, there is no guarantee the underlying fund’s arbitrage mechanism will operate as intended and that the underlying fund will not experience wide bid/ask spreads and/or large discounts or premiums to NAV. In addition, market participants may attempt to use the disclosed information to “reverse engineer” the underlying fund’s trading strategy, which, if successful, could increase opportunities for predatory trading practices that may have the potential to negatively impact the underlying fund’s performance. These practices may include front running (trading ahead of the underlying fund) or free riding (mirroring the underlying fund’s strategies).

Trading halt risk. (For Sustainable Leaders ETF and Sustainable Future ETF) There may be circumstances where a security held in the underlying fund’s portfolio but not in the Tracking Basket does not have readily available market quotations. If the underlying fund’s manager determines that such circumstance may affect the reliability of the Tracking Basket as an arbitrage vehicle, that information, along with the identity and weighting of that security in the underlying fund’s portfolio, will be publicly disclosed on the underlying fund’s website and the underlying fund’s manager will assess appropriate remedial measures. In these circumstances, market participants may use this information to engage in certain predatory trading practices that may have the potential to harm the underlying fund and its shareholders. In addition, if securities representing 10% or more of the underlying fund’s portfolio do not have readily available market quotations, the underlying fund’s manager would promptly request the exchange to halt trading on the underlying fund, meaning that your fund would not be able to trade its shares. Trading may also be halted in other circumstances, for example, due to market conditions.

Additional Risks

Liquidity and illiquid investments. Each underlying fund may invest up to 15% of its net assets in illiquid investments, which may be considered speculative and may be difficult to sell. The sale of many of these investments is prohibited or limited by law or contract. Some investments may be difficult to value for purposes of determining an underlying fund’s NAV. Certain other investments may not have an active trading market due to adverse market, economic, industry, political, regulatory, geopolitical, environmental, public health, and other conditions, including investors trying to sell large quantities of a particular investment or type of investment, or lack of market makers or other buyers for a particular investment or type of investment. An underlying fund may not be able to sell its illiquid investments when the underlying fund manager considers it desirable to do so, or the underlying fund may be able to sell them only at less than their value.

Other investments. (For all underlying funds except Sustainable Leaders ETF and Sustainable Future ETF)

PanAgora International Equity ETF and PanAgora Emerging Markets Equity ETF may also invest in cash or cash equivalents, including money market instruments or short-term instruments such as commercial paper, bank obligations (e.g., certificates of deposit and bankers’ acceptances), repurchase agreements, and U.S. Treasury bills or other government obligations.

Core Bond ETF may make other types of investments, such as investments in preferred stocks, convertible securities asset-backed securities.

High Yield ETF may make other types of investments, such as investments in equity securities, asset- backed, hybrid and structured bonds and notes, preferred securities that would be characterized as debt securities under applicable accounting standards and tax laws, and assignments of and participations in fixed and floating rate loans.

Ultra Short ETF may make other types of investments, such as investments in hybrid and structured bonds and notes, and preferred securities that would be characterized as debt securities under applicable accounting standards and tax laws.

An underlying fund may also invest in cash or cash equivalents, including money market instruments or short-term instruments such as commercial paper, bank obligations (e.g., certificates of deposit and bankers’ acceptances), repurchase agreements, and U.S. Treasury bills or other government obligations. An underlying fund may also from time to time invest all or a portion of its cash balances in money market and/or short-term bond funds advised by an underlying fund manager or its affiliates. The percentage of an underlying fund invested in cash and cash equivalents and such money market and short-term bond funds is expected to vary over time and will depend on various factors, including market conditions, purchase and redemption activity by fund shareholders, and an underlying fund manager’s assessment of the cash level that is appropriate to allow the underlying fund to pursue investment opportunities as they arise and to meet shareholder redemption requests. Large cash positions may dampen performance and may prevent an underlying fund from achieving its goal. An underlying fund may also loan portfolio securities to earn income. These practices may be subject to other risks, as described under Miscellaneous Investments, Investment Practices and Risks in the SAI.

Temporary defensive strategies. In response to adverse market, economic, political or other conditions, an underlying fund manager may take temporary defensive positions, such as investing some or all of an underlying fund’s assets in cash and cash equivalents that differ from an underlying fund’s usual investment strategies. However, an underlying fund manager may choose not to use these temporary defensive strategies for a variety of reasons, even in very volatile market conditions. If an underlying fund manager does employ these strategies, an underlying fund may miss out on investment opportunities and may not achieve its goal. Additionally, while temporary defensive strategies are mainly designed to limit losses, they may not work as intended.

Changes in policies. The Trustees may change a fund’s or an underlying fund’s goal, investment strategies and other policies set forth in this prospectus/information statement without shareholder approval, except as otherwise provided in the prospectus or SAI.

Portfolio turnover rate. A fund’s portfolio turnover rate measures how frequently a fund buys and sells investments. A portfolio turnover rate of 100%, for example, would mean that a fund sold and replaced securities valued at 100% of the fund’s assets within a one-year period. From time to time an underlying fund may engage in frequent trading. Funds with high turnover may be more likely to realize capital gains that must be distributed to shareholders as taxable income. High turnover may also cause a fund to pay more brokerage commissions and to incur other transaction costs (including imputed transaction costs), which may detract from performance. A fund’s portfolio turnover rate and the amount of brokerage commissions it pays and transactions costs it incurs will vary over time based on market conditions. Each fund’s portfolio turnover rate for the most recent fiscal year was higher than is expected going forward due to portfolio realignment resulting from the repositioning of each fund’s investment strategy in February 2023.

Portfolio holdings. The SAI includes a description of each fund’s policies with respect to the disclosure of its portfolio holdings. For more specific information on a fund’s portfolio, you may visit www.franklintempleton.com. Each underlying fund’s top 10 holdings and related portfolio information may be viewed monthly beginning on or after 5 business days after the end of each month, and full portfolio holdings of each underlying fund may be viewed monthly beginning on or before the 15th calendar day after the end of each month. This information will remain available on the website at least until a fund files a Form N-CSR or publicly available Form N-PORT with the SEC for the period that includes the date of the information, after which such information can be found on the SEC’s website at http://www.sec.gov.

Additionally, the complete portfolio holdings for each of Core Bond ETF, High Yield ETF, Ultra Short ETF, PanAgora Emerging Markets Equity ETF and PanAgora International Equity ETF may be viewed on each business day, before commencement of trading in shares on the listing exchange.

III. Information about the Merger

General. Putnam Sustainable Retirement 2025 Fund will merge with and into Putnam Sustainable Retirement Maturity Fund pursuant to an Agreement and Plan of Reorganization (the “Plan”).

Although the term “merger” is used for ease of reference, the transaction is structured as a transfer of all of the assets of Putnam Sustainable Retirement 2025 Fund to Putnam Sustainable Retirement Maturity Fund in exchange for the assumption by Putnam Sustainable Retirement Maturity Fund of all of the liabilities of Putnam Sustainable Retirement 2025 Fund and for the issuance and delivery to Putnam Sustainable Retirement 2025 Fund of shares of Putnam Sustainable Retirement Maturity Fund (the Merger Shares) equal in aggregate net asset value to the value of the assets transferred to Putnam Sustainable Retirement Maturity Fund.

After receipt of the Merger Shares, Putnam Sustainable Retirement 2025 Fund will distribute the Merger Shares to its shareholders, in proportion to their existing shareholdings, in complete liquidation of Putnam Sustainable Retirement 2025 Fund, and the legal existence of Putnam Sustainable Retirement 2025 Fund will be terminated. Each shareholder of Putnam Sustainable Retirement 2025 Fund will receive a number of full and fractional Merger Shares equal in value at the date of the exchange to the aggregate value of the shareholder’s Putnam Sustainable Retirement 2025 Fund shares.

Before the date of the merger, Putnam Sustainable Retirement 2025 Fund will declare a distribution to shareholders that, together with all previous distributions qualifying for the dividends-paid deduction, will have the effect of distributing to shareholders all of its remaining investment company taxable income (computed without regard to the deduction for dividends paid), net tax-exempt income (if any), and net realized capital gains, if any, through the date of the transfer.

The Trustees have voted unanimously to approve the merger.

Please see “Federal Income Tax Consequences” for information about the expected tax consequences of the merger.

WE ARE NOT ASKING YOU FOR A PROXY AND YOU ARE REQUESTED NOT TO SEND US A PROXY

Fees and Expenses.

Shareholder Fees (fees paid directly from your investment)
Putnam Sustainable Retirement Maturity Fund

Annual Fund Operating Expenses (expenses that are deducted from fund assets)
Putnam Sustainable Retirement 2025 Fund

Annual Fund Operating Expenses (expenses that are deducted from fund assets)
Putnam Sustainable Retirement Maturity Fund

Annual Fund Operating Expenses (expenses that are deducted from fund assets)
Putnam Sustainable Retirement Maturity Fund (pro forma combined)†

The tables are provided to help you understand the expenses of investing in the funds and your share of the operating expenses that each fund incurs and that the Investment Manager expects the combined fund to incur in the first year following the merger.

Examples

Trustees’ Considerations Relating to the Merger. The Trustees of The Putnam Funds, who serve as Trustees of each of the funds involved in the merger, have carefully considered the anticipated benefits and costs of the merger from the perspective of each fund. Following their review, the Trustees, including all of the Independent Trustees, determined that the merger of Putnam Sustainable Retirement 2025 Fund into Putnam Sustainable Retirement Maturity Fund would be in the best interests of each fund and its shareholders and that the interests of existing shareholders of each fund would not be diluted by the merger. The Trustees unanimously approved the merger and the Plan.

Investment matters. In evaluating the merger, the Trustees analyzed the underlying investment rationale articulated by the Investment Manager. The Trustees noted that the funds have similar investment goals, pursue similar investment strategies and have identical fundamental investment restrictions. The Trustees considered that the funds have been managed by the same portfolio managers and that, in the target date year, Putnam Sustainable Retirement 2025 Fund’s allocations among asset classes and underlying funds will correspond to those of the Putnam Sustainable Retirement Maturity Fund, which seeks as high a rate of current income as the Investment Manager believes is consistent with preservation of capital. The Trustees further considered that the funds’ prospectus discloses that Putnam Sustainable Retirement 2025 Fund will merge into Putnam Sustainable Retirement Maturity Fund in the target date year (2025).

The Trustees considered that the funds’ portfolio managers, Mr. Chan, Mr. Goldstein, Ms. Belknap, Mr. Nelson and Mr. Schreiber, have served as portfolio managers of each of Putnam Sustainable Retirement 2025 Fund and Putnam Sustainable Retirement Maturity Fund since 2021, 2019, 2019 and 2019, respectively.

Performance. The Trustees reviewed the historical investment performance of each fund and observed that, as of the periods ended December 31, 2024, Putnam Sustainable Retirement 2025 Fund outperformed Putnam Sustainable Retirement Maturity Fund over the one-, five- and ten- year periods and that Putnam Sustainable Retirement Maturity Fund outperformed Putnam Sustainable Retirement 2025 Fund over the three-year period. The difference in performance is primarily driven by the higher equity allocation in Putnam Sustainable Retirement 2025 Fund as it continued to roll down the glide path to retirement.

Ongoing fund expenses. The Trustees reviewed the annual fund operating expenses that Putnam Sustainable Retirement Maturity Fund shareholders and Putnam Sustainable Retirement 2025 Fund shareholders were expected to experience as a result of the merger, based on the Investment Manager’s unaudited estimates of the funds’ expense ratios as of January 31, 2025 and the expected pro forma expense ratios based on combined assets of the funds as of the same date. They noted that the shareholders of Putnam Sustainable Retirement Maturity Fund would pay a slightly lower management fee and total annual fund operating expenses (gross) as a percent of net assets than do the shareholders of Putnam Sustainable Retirement 2025 Fund.

The Trustees also considered the Investment Manager’s representation that the funds would not incur any portfolio transaction costs as a result of the merger because the funds’ portfolio allocations will correspond prior the merger.

Additional information that the Trustees considered is presented in “Questions and Answers Regarding the Merger—5. How do the management fees and other expenses of the funds compare, and what are they estimated to be following the merger?” and in “Information about the Merger—Fees and Expenses.”

Tax matters. The Trustees also considered the tax effects of the merger. The Trustees took into account the fact that, although this result is not free from doubt, the merger is expected to be a tax-free transaction for federal income tax purposes. They also took into account other anticipated tax effects of the merger, including the consequences that the blending of existing tax attributes of the two funds would have on taxable shareholders.

Costs of the merger. The Trustees took into account the expected costs of the merger, including the costs of printing and mailing this prospectus/information statement, accounting fees and legal fees. The Trustees weighed these costs against the expected benefits of the merger. The Trustees considered the Investment Manager’s recommendation that, since both funds are expected to benefit from the merger, the costs be allocated evenly between the two funds except that the SEC filing fees be allocated between the two funds pro rata based on fund assets. The Trustees further considered that the costs identified below will borne by the Investment Manager in light of the expense limitation arrangements in place for the funds:

Agreement and Plan of Reorganization. The merger will be governed by the Plan. The following discussion of the Plan is a summary provided for your reference only.

The Plan provides that Putnam Sustainable Retirement Maturity Fund will acquire all of the assets of Putnam Sustainable Retirement 2025 Fund in exchange for the assumption by Putnam Sustainable Retirement Maturity Fund of all of the liabilities of Putnam Sustainable Retirement 2025 Fund and for the issuance of full and fractional Merger Shares of each class equal in value to the value of the transferred assets attributable to shares of the corresponding class of Putnam Sustainable Retirement 2025 Fund net of assumed liabilities attributable to the class. Valuations for the merger will be determined as of 4:00 p.m., Eastern Time, on July 25, 2025, or such earlier or later time or date as may be agreed upon by the parties (the “Valuation Time”). The shares will be issued on the business day (the “Exchange Date”) following the Valuation Time.

Putnam Sustainable Retirement Maturity Fund, the acquiring fund, will issue the Merger Shares to Putnam Sustainable Retirement 2025 Fund, registered in the name of Putnam Sustainable Retirement 2025 Fund, to Putnam Sustainable Retirement 2025 Fund. Immediately following its receipt of the Merger Shares on the Exchange Date, Putnam Sustainable Retirement 2025 Fund will distribute the full and fractional Merger Shares of each class, pro rata, to its shareholders of that class of record as of the close of business on the Exchange Date. Putnam Sustainable Retirement Maturity Fund will then, in accordance with written instructions furnished by Putnam Sustainable Retirement 2025 Fund, re-register the Merger Shares in the names of the shareholders of Putnam Sustainable Retirement 2025 Fund in an amount representing the number of full and fractional Merger Shares of each class due the shareholder. As a result of the proposed merger, each shareholder of Putnam Sustainable Retirement 2025 Fund will receive a number of Merger Shares of each class equal in aggregate value at the Exchange Date to the value of Putnam Sustainable Retirement 2025 Fund shares of the corresponding class held by the shareholder.

The consummation of the merger is subject to the conditions set forth in the Plan. The Plan may be terminated and the merger abandoned at any time before the Exchange Date by mutual consent of Putnam Sustainable Retirement Maturity Fund and Putnam Sustainable Retirement 2025 Fund or, if any condition set forth in the Plan has not been fulfilled and has not been waived by the party entitled to its benefits, by that party.

The Investment Manager will bear the costs of the merger in light of the expense limitation arrangements in place for the funds. The costs associated with the merger are estimated to be $141,197. These costs, representing legal and accounting expenses, portfolio transfer taxes (if any), the costs of printing and mailing this prospectus/information statement, SEC filing fees or other similar expenses incurred in connection with the consummation of the merger, will be allocated evenly between the two funds except that the SEC filing fees (estimated to be $361) will be allocated between the two funds pro rata based on fund assets. This is expected to result in an estimated $70,637 being allocated to Putnam Sustainable Retirement 2025 Fund and an estimated $70,560 being allocated to Putnam Sustainable Retirement Maturity Fund. Because both funds are expected to benefit from the merger based on several factors, the Investment Manager determined that the allocation described above is a fair and objective manner of allocating the merger expenses. However, as noted above, under the current expense limitation agreements with the funds, the Investment Manager will bear all of these costs.

Because each fund’s investment allocations will correspond to the other’s at the time of the merger, the Investment Manager does not currently anticipate any portfolio realignment or related transaction costs in connection with the merger.

Description of the Merger Shares. The Merger Shares are Class A, class C, class R, class R3, class R4, class R5, class R6, and class Y shares of Putnam Sustainable Retirement Maturity Fund. Each class of Merger Shares has identical characteristics to shares of the corresponding class of Putnam Sustainable Retirement 2025 Fund. Putnam Sustainable Retirement 2025 Fund shareholders receiving Merger Shares will not pay an initial sales charge on the shares. Your Merger Shares will be subject to a contingent deferred sales charge to the same extent that your Putnam Sustainable Retirement 2025 Fund shares were subject to such a charge. In other words, your Merger Shares will be treated as having been purchased on the date you purchased your Putnam Sustainable Retirement 2025 Fund shares and for the price you originally paid, potentially subject to certain adjustments. For more detail on the characteristics of each class of Merger Shares, please see the “How do I buy fund shares?” section of the prospectus of Putnam Sustainable Retirement Maturity Fund, dated December 31, 2024, as supplemented.

Under Massachusetts law, shareholders could, under certain circumstances, be held personally liable for the obligations of Putnam Sustainable Retirement Maturity Fund. However, the Amended and Restated Agreement and Declaration of Trust of Putnam Sustainable Retirement Maturity Fund disclaims shareholder liability for acts or obligations of Putnam Sustainable Retirement Maturity Fund and requires that notice of such disclaimer be given in each agreement, obligation or instrument entered into or executed by Putnam Sustainable Retirement Maturity Fund or its Trustees. The Amended and Restated Agreement and Declaration of Trust provides for indemnification out of fund property for all loss and expense of any shareholder held personally liable for the obligations of Putnam Sustainable Retirement Maturity Fund. Thus, the risk of a shareholder incurring financial loss on account of shareholder liability is limited to circumstances in which Putnam Sustainable Retirement Maturity Fund would be unable to meet its obligations. The likelihood of such circumstances is remote. The shareholders of Putnam Sustainable Retirement 2025 Fund are currently subject to this same risk of shareholder liability.

Federal Income Tax Consequences. As a condition to each fund’s obligation to consummate the transactions contemplated by the Plan, the funds will receive a tax opinion from Ropes & Gray LLP, counsel to the funds (which opinion will be based on certain factual representations and customary assumptions and subject to certain qualifications), substantially to the effect that, although the matter is not free from doubt, on the basis of the existing provisions of the Code, Treasury regulations promulgated thereunder, current administrative rules and court decisions, generally for U.S. federal income tax purposes:

Putnam Sustainable Retirement Maturity Fund will file the tax opinion with the SEC shortly after completion of the merger. The opinion will be based on certain factual certifications made by officers of Putnam Sustainable Retirement 2025 Fund and Putnam Sustainable Retirement Maturity Fund and will also be based on customary assumptions and subject to certain qualifications. The opinion may note and distinguish certain published precedent. The opinion is not a guarantee that the tax consequences of the merger will be as described above. There is no assurance that the Internal Revenue Service will agree with the opinion. If the merger were consummated but did not qualify as a tax-free reorganization, Putnam Sustainable Retirement 2025 Fund shareholders would recognize a taxable gain or loss equal to the difference between their tax basis in their Putnam Sustainable Retirement 2025 Fund shares and the fair market value of the shares of Putnam Sustainable Retirement Maturity Fund received.

Although the merger is expected to be a tax-free reorganization for federal income tax purposes, there will nonetheless be tax implications. Portfolio assets of Putnam Sustainable Retirement 2025 Fund may be sold in connection with the merger. The actual tax impact of any such sales will depend on the difference between the price at which the portfolio assets are sold and Putnam Sustainable Retirement 2025 Fund’s tax basis in the assets. If such sales take place prior to the date of the merger, any net capital gains recognized in these sales will be distributed to Putnam Sustainable Retirement 2025 Fund’s shareholders as capital gain dividends (to the extent of net realized long-term capital gains over net- realized short-term capital losses) and/or ordinary dividends (to the extent of net realized short-term capital gains over net realized long-term capital losses) during or with respect to the year of sale. Such distributions will be taxable to shareholders. If such sales take place after the date of the merger, any net capital gains recognized in these sales will be distributed to shareholders of the combined fund and will be taxable to shareholders in the manner described in the immediately preceding sentence. Also, because the merger will end the tax year of Putnam Sustainable Retirement 2025 Fund, it could accelerate distributions to shareholders from Putnam Sustainable Retirement 2025 Fund for its short tax year ending on the date of the merger. Those tax year-end distributions will be taxable and will include any capital gains resulting from portfolio turnover prior to the merger. The Investment Manager currently does not anticipate any portfolio realignment in connection with the merger.

Before consummating the merger, Putnam Sustainable Retirement 2025 Fund will, and Putnam Sustainable Retirement Maturity Fund may, declare a distribution to shareholders that, together with all previous distributions qualifying for the dividends-paid deduction, will have the effect of distributing to shareholders, all of its investment company taxable income (computed without regard to the deduction for dividends paid), net tax-exempt income (if any), and net capital gains, including those realized on the disposition of portfolio securities, whether independent of or in connection with the merger, effected prior to the merger. These distributions will generally be taxable to shareholders.

Furthermore, differences between the funds’ unrealized gains and losses and tax loss carryforwards, and tax rules limiting the use of certain of those losses to offset gains following the merger, may affect the timing and amount of future capital gain distributions paid to shareholders. Putnam Sustainable Retirement Maturity Fund’s ability to carry forward its or Putnam Sustainable Retirement 2025 Fund’s pre- merger capital losses and to use them to offset future gains may be limited as a result of the merger. First, “pre-acquisition losses” of either Putnam Sustainable Retirement Maturity Fund or Putnam Sustainable Retirement 2025 Fund (including capital loss carryforwards, net current-year capital losses, and unrealized losses that exceed certain thresholds) may become unavailable to offset gains of the combined fund. Second, one fund’s pre-acquisition losses cannot be used to offset unrealized gains in the other fund that are “built in” at the time of the merger and that exceed certain thresholds (“non-de minimis built- in gains”) for five tax years. Third, Putnam Sustainable Retirement 2025 Fund’s loss carryforwards, as limited under the previous two rules, are permitted to offset only that portion of the income of Putnam Sustainable Retirement Maturity Fund for the taxable year of the merger that is equal to the portion of Putnam Sustainable Retirement Maturity Fund’s taxable year that follows the date of the merger (prorated according to number of days). Therefore, in certain circumstances, shareholders of either fund may pay taxes sooner, or pay more taxes, than they would have had the merger not occurred.

In addition, the combined fund resulting from the merger will have tax attributes that reflect a blending of the tax attributes of Putnam Sustainable Retirement Maturity Fund and Putnam Sustainable Retirement 2025 Fund at the time of the merger (including as affected by the rules described above). Therefore, the shareholders of each fund will receive a proportionate share of any “built-in” (unrealized) gains in the other fund’s assets, if any, as well as, in the case of Putnam Sustainable Retirement 2025 Fund shareholders, taxable gains, if any, realized by Putnam Sustainable Retirement Maturity Fund but not distributed to its shareholders before the merger, when Putnam Sustainable Retirement Maturity Fund eventually distributes those gains. As a result, shareholders of either fund may receive a greater amount of taxable distributions than they would have had the merger not occurred. Any pre-acquisition losses of Putnam Sustainable Retirement 2025 Fund (whether realized or unrealized) remaining after the operation of the limitation rules described above will become potentially available to offset capital gains realized after the merger and thus may reduce subsequent capital gain distributions to a broader group of shareholders than would have been the case absent the merger, such that the benefit of those losses to Putnam Sustainable Retirement 2025 Fund shareholders may be further reduced relative to what the benefit would have been had the merger not occurred.

The amount of realized and unrealized gains and losses of each fund, as well as the size of each fund, at the time of the merger will determine the extent to which the funds’ respective losses, both realized and unrealized, will be available to reduce gains realized by the combined fund following the merger, and consequently the extent to which the combined fund may be required to distribute gains to its shareholders earlier than would have been the case absent the merger. Thus, the impact of the rules described above will depend on factors that are currently unknown, and this impact cannot be calculated precisely before the merger.

The following paragraphs and tables provide a brief summary of the tax impacts, due to the above- described rules and the combination of the tax attributes of the two funds, of the merger had it occurred on February 28, 2025. The summary is based on the gain/loss characteristics of the funds as of February 28, 2025 and assumes that a hypothetical merger of the funds took place on that date. The gain/loss characteristics and net assets of each fund, and of the combined fund, on the actual date of the merger will differ, perhaps significantly, from those on February 28, 2025. For example, as a result of any potential portfolio turnover of Putnam Sustainable Retirement 2025 Fund, that fund’s tax situation, and thus the actual tax impacts of the merger, could differ substantially from those described below. Because the tax impact of the merger depends on each fund’s relative tax situation at the time of the merger, which situation will be different, and perhaps significantly different, than the tax situation on February 28, 2025, the tax impacts of the merger will differ, perhaps significantly, from those described below.

As of February 28 , 2025 Putnam Sustainable Retirement 2025 Fund had net realized losses (in the form of capital loss carryforwards net of year-to-date (“YTD”) net realized gains) equal to approximately $25,973,749, or roughly 7.01% of its own NAV, and net built-in gains equal to approximately $13,737,462, or roughly 3.71% of its own NAV, and Putnam Sustainable Retirement Maturity Fund had net realized losses (also in the form of capital loss carryforwards net of YTD net realized gains) equal to approximately $39,893,987, or roughly 18.58%% of its own NAV, and net built-in gains equal to approximately $13,471,769, or roughly 6.27% of its own NAV. Had the merger occurred on February 28, 2025, the combined fund would have had capital loss carryforwards net of YTD realized gains of approximately $65,867,73, or roughly 11.25% of the NAV of the combined fund, and unrealized gains equal to approximately $27,209,231, or roughly 4.65% of the NAV of the combined fund. As of February 28, 2025, Putnam Sustainable Retirement Maturity Fund had proportionately larger capital loss carryforwards net of YTD realized gains than Putnam Sustainable Retirement 2025 Fund. The merging Funds’ unrealized gains as a percentage of NAV were of a similar magnitude. As a result of the hypothetical merger occurring on February 28, 2025, each Fund’s pre-merger losses and unrealized gains would have been spread among all shareholders of the combined fund.

Had the merger occurred on February 28, 2025, the annual loss limitation rules of Section 382 would have applied to Putnam Sustainable Retirement Maturity Fund’s losses. As a result, the merger may have resulted in the deferral of the use of a portion of Putnam Sustainable Retirement Maturity Fund’s losses.

Putnam Sustainable Retirement Maturity Fund’s loss carryforwards, as limited by the applicable rules described above, would be permitted to offset only that portion of the income of the combined fund for the taxable year of the merger that is equal to the portion of combined fund’s taxable year that follows the date of the merger (i.e., in the case of a hypothetical merger date of February 28, 2025, February 28, 2025 to July 31, 2025) prorated according to the number of days.

The tax principles described above are not expected to change. However, their application will change prior to the merger because of market developments and fluctuation, any pre-merger realignments or other sales of portfolio securities that might occur or that have already occurred, and shareholder activity in the funds, among other changes. This description of the federal income tax consequences of the merger is made without regard to the particular facts and circumstances of any shareholder, though it is relevant only to a situation when a fund’s shares are held in a taxable account. Shareholders are urged to consult their own tax advisors as to the specific consequences to them of the merger, including the applicability and effect of state, local and other tax laws.

Capitalization. The following table shows on an unaudited basis the capitalization of the funds as of April 11, 2025, and on a pro forma combined basis, giving effect to the merger as of that date:

Class A: 1,016,213

Class C: 24,322

Class R: 28,601

Class R3: 59,706

Class R4: 3,375

Class R5: 542

Class R6: 15,615

Class Y: 9,415,825

Unaudited narrative pro forma financial information of the funds for the six-month period ended January 31, 2025 included in the Merger SAI. Because the Plan provides that Putnam Sustainable Retirement Maturity Fund will be the surviving fund following the merger and because Putnam Sustainable Retirement Maturity Fund’s investment goals and policies will remain unchanged, the narrative pro forma financial information reflects the transfer of the assets and liabilities of Putnam Sustainable Retirement 2025 Fund to Putnam Sustainable Retirement Maturity Fund as contemplated by the Plan.

IV. Additional Information about Putnam Sustainable Retirement Maturity Fund

References to the “fund” in this section refer to Putnam Sustainable Retirement Maturity Fund.

Purchase and sale of fund shares

You can open an account, purchase and/or sell fund shares, or exchange them for shares of another Putnam fund by contacting your financial professional or by calling Putnam Investor Services at 1-800- 225-1581.

When opening an account, you must complete and mail a Putnam account application, along with a check made payable to the fund, to: Putnam Investor Services, P.O. Box 219697, Kansas City, MO 64121-9697. The minimum initial investment of $500 is currently waived, although the fund reserves the right to reject initial investments under $500 at its discretion. There is no minimum for subsequent investments.

You can sell your shares back to the fund or exchange them for shares of another Putnam fund any day the New York Stock Exchange (NYSE) is open. Shares may be sold or exchanged by mail, by phone, or, for exchanges only, online at www.franklintempleton.com. Some restrictions may apply.

Tax Information

The fund’s distributions will be taxed as ordinary income or capital gains unless you hold the shares through a tax-advantaged arrangement, in which case you will generally be taxed only upon withdrawal of monies from the arrangement.

Financial Intermediary Compensation

If you purchase the fund through a broker/dealer or other financial intermediary (such as a bank or financial professional), the fund and its related companies may pay that intermediary for the sale of fund shares and related services. Please bear in mind that these payments may create a conflict of interest by influencing the broker/dealer or other intermediary to recommend the fund over another investment. Ask your advisor or visit your advisor’s website for more information.

Who oversees and manages the fund?

The fund’s Trustees

As a shareholder of a mutual fund, you have certain rights and protections, including representation by a Board of Trustees. The Putnam Funds’ Board of Trustees oversees the general conduct of the fund’s business and represents the interests of the Putnam fund shareholders. At least 75% of the members of the Putnam Funds’ Board of Trustees are independent, which means they are not officers of the fund or affiliated with the Investment Manager.

The Trustees periodically review the fund’s investment performance and the quality of other services such as administration, custody, and investor services. At least annually, the Trustees review the fees paid to the Investment Manager and its affiliates for providing or overseeing these services, as well as the overall level of the fund’s operating expenses. In carrying out their responsibilities, the Trustees are assisted by an administrative staff, auditors and legal counsel that are selected by the Trustees and are independent of the Investment Manager and its affiliates.

Contacting the fund’s Trustees

Address correspondence to:

The Putnam Funds Trustees

100 Federal Street

Boston, MA 02110

The fund’s investment manager

The Trustees have retained the Investment Manager, a global investment management organization based in California, to be the fund’s investment manager, responsible for making investment decisions for the fund and managing the fund’s other affairs and business.

The fund pays a management fee to the Investment Manager. The fee for the fund is calculated and paid monthly based on an annual rate of 0.46% and the fund’s average net assets for the month.

The Investment Manager’s address is One Franklin Parkway, San Mateo, CA 94403-1906.

The Investment Manager has retained its affiliate, Putnam Management, to provide certain advisory and related services. The Investment Manager (and not the fund) will pay a monthly fee to Putnam Management based on the costs of Putnam Management in providing these services to the fund, which may include a mark-up determined and revised from time-to-time in accordance with Franklin Resources, Inc.’s (“Franklin Templeton”) transfer pricing policy, in line with applicable tax/transfer pricing regulations, but not to exceed 15% over such costs. Putnam Management, which is one of America’s oldest money management firms, is located at 100 Federal Street, Boston, MA 02110.

The Investment Manager has also retained its affiliate Franklin Templeton Investment Management (“FTIML”) to make investment decisions for such fund assets as may be designated from time to time for its management by the Investment Manager. FTIML is not currently managing any fund assets. If FTIML were to manage any fund assets, the Investment Manager (and not the fund) will pay a monthly sub- management fee to FTIML for its services at the annual rate of 0.25% of the average net asset value (NAV) of any fund assets managed by FTIML. FTIML, is located at Cannon Place, 78 Cannon Street, London, England, EC4N 6HL.

Pursuant to these arrangements, investment professionals who are based in foreign jurisdictions may serve as portfolio managers of the fund or provide other investment services, consistent with local regulations.

The Investment Manager, Putnam Management and FTIML are each direct or indirect, wholly-owned subsidiaries of Franklin Templeton.

Portfolio managers. The portfolio managers identified below are jointly and primarily responsible for the day-to-day management of the fund’s portfolio.

The SAI provides information about these individuals’ compensation, other accounts managed by these individuals and these individuals’ ownership of securities in the fund.

How does the fund price its shares?

The price of the fund’s shares is based on its NAV, which in turn will be generally based on the last sale price or closing price of the underlying funds in which it invests. For a description of the circumstances under which the underlying funds use fair value pricing and the effects of using fair value pricing, please see the underlying funds’ prospectuses. The NAV per share of each class equals the total value of its assets, less its liabilities, divided by the number of its outstanding shares. Shares are only valued as of the scheduled close of regular trading on the NYSE each day the exchange is open.

The fund’s most recent NAV is available at www.franklintempleton.com or by contacting Putnam Investor Services at 1-800-225-1581.

How do I buy fund shares?

Opening an account

You can open a fund account and purchase class A and C shares by contacting your financial representative or Putnam Investor Services at 1-800-225-1581 and obtaining a Putnam account application. The completed application, along with a check made payable to the fund, must then be returned to Putnam Investor Services at the following address:

Putnam Investor Services

P.O. Box 219697

Kansas City, MO 64121-9697

You can open a fund account with as little as $500. The minimum investment is waived if you make regular investments weekly, semi-monthly or monthly through automatic deductions from your bank checking or savings account. Although Putnam is currently waiving this minimum, it reserves the right to reject initial investments under the minimum at its discretion.

The fund sells its shares at the offering price, which is the NAV plus any applicable sales charge (class A shares only). Your financial representative or Putnam Investor Services generally must receive your completed buy order before the close of regular trading on the NYSE for your shares to be bought at that day’s offering price.

If you participate in an employer-sponsored retirement plan that offers the fund, please consult your employer for information on how to purchase shares of the fund through the plan, including any restrictions or limitations that may apply.

Federal law requires mutual funds to obtain, verify, and record information that identifies investors opening new accounts. Investors must provide their full name, residential or business address, Social Security or tax identification number, and date of birth. Entities, such as trusts, estates, corporations and partnerships must also provide additional identifying documentation. For trusts, the fund must obtain and verify identifying information for each trustee listed in the account registration. For certain legal entities, the fund must also obtain and verify identifying information regarding beneficial owners and/or control persons. The fund is unable to accept new accounts if any required information is not provided. If Putnam Investor Services cannot verify identifying information after opening your account, the fund reserves the right to close your account at the then-current NAV, which may be more or less than your original investment, net of any applicable sales charges. Putnam Investor Services may share identifying information with third parties for the purpose of verification subject to the terms of Putnam’s privacy policy.

Also, the fund may periodically close to new purchases of shares or refuse any order to buy shares if the fund determines that doing so would be in the best interests of the fund and its shareholders.

Purchasing additional shares

Once you have an existing account, you can make additional investments at any time in any amount in the following ways:

Which class of shares is best for me?

Investors other than employer-sponsored retirement plans that are clients of third-party administrators (including affiliates of Putnam) that have entered into agreements with Putnam may choose class A or C shares (the purchase of class A and C shares by such employer- sponsored retirement plans will not be permitted). Employer-sponsored retirement plans may choose class R, R3, R4, R5 or R6 shares, and certain investors described below may also choose class Y or R6 shares.

Employer-sponsored retirement plans whose administrator has not entered into an agreement with Putnam regarding defined contribution plan servicing, may continue to choose class A or C shares or, if otherwise eligible, class Y shares.

Each share class represents investments in the same portfolio of securities, but each class has its own sales charge and expense structure, as illustrated in the Fund summaries — Fees and expenses section, allowing you and your financial representative to choose the class that best suits your investment needs. When you purchase shares of the fund, you must choose a share class. Deciding which share class best suits your situation depends on a number of factors that you should discuss with your financial representative, including:

Here is a summary of the differences among the classes of shares

Class A shares (available except for employer-sponsored retirement plans that are clients of third-party administrators (including affiliates of Putnam) that have entered into agreements with Putnam)

Class C shares (available except for employer-sponsored retirement plans that are clients of third-party administrators (including affiliates of Putnam) that have entered into agreements with Putnam)

Class R6 shares

The following investors may purchase class R6 shares:

Class Y shares

The following investors may purchase class Y shares if approved by Putnam:

Trust companies or bank trust departments that purchased class Y shares for trust accounts may transfer them to the beneficiaries of the trust accounts, who may continue to hold them or exchange them for class Y shares of other Putnam funds. Defined contribution plans (including corporate IRAs) that purchased class Y shares under prior eligibility criteria may continue to purchase class Y shares.

Share classes available to employer-sponsored retirement plans that are clients of third-party administrators (including affiliates of Putnam) that have entered into agreements with Putnam)

Class R shares (available only to employer-sponsored retirement plans that are clients of third-party administrators (including affiliates of the Investment Manager) that have entered into agreements with the Investment Manager)

Class R3 shares (available only to employer-sponsored retirement plans that are clients of third-party administrators (including affiliates of Putnam) that have entered into agreements with Putnam)

Class R4 shares (available only to employer-sponsored retirement plans that are clients of third-party administrators (including affiliates of Putnam) that have entered into agreements with Putnam)

Class R5 shares (available only to employer-sponsored retirement plans that are clients of third-party administrators (including affiliates of Putnam) that have entered into agreements with Putnam)

Initial sales charges for class A shares

Reducing your class A sales charge

The fund offers two principal ways for you to qualify for discounts on initial sales charges on class A shares, often referred to as “breakpoint discounts”:

Right of accumulation. You can add the amount of your current purchases of class A shares of the fund and other Putnam funds (excluding Putnam Ultra Short MAC Series) to the value of your existing accounts in the fund and other Putnam funds (excluding Putnam Ultra Short MAC Series). Individuals can also include purchases by, and accounts owned by, their spouse and minor children, including accounts established through different financial representatives. For your current purchases, you will pay the initial sales charge applicable to the total value of the linked accounts and purchases, which may be lower than the sales charge otherwise applicable to each of your current purchases. In addition to Putnam Ultra Short MAC Series, shares of Putnam money market funds, other than money market fund shares acquired by exchange from other Putnam funds, are not included for purposes of the right of accumulation.

To calculate the total value of your existing accounts and any linked accounts, the fund will use the higher of (a) the current maximum public offering price of those shares or (b) if you purchased the shares after December 31, 2007, the initial value of the total purchases, or, if you held the shares on December 31, 2007, the market value at maximum public offering price on that date, in either case, less the market value on the applicable redemption date of any of those shares that you have redeemed.

Statement of intention. A statement of intention is a document in which you agree to make purchases of class A shares in a specified amount within a period of 13 months. For each purchase you make under the statement of intention, you will pay the initial sales charge applicable to the total amount you have agreed to purchase. While a statement of intention is not a binding obligation on you, if you do not purchase the full amount of shares within 13 months, the fund will redeem shares from your account in an amount equal to the difference between the higher initial sales charge you would have paid in the absence of the statement of intention and the initial sales charge you actually paid.

In order to obtain a breakpoint discount, you should inform your financial representative at the time you purchase shares of the existence of other accounts or purchases that are eligible to be linked for the purpose of calculating the initial sales charge. The fund or your financial representative may ask you for records or other information about other shares held in your accounts and linked accounts, including accounts opened with a different financial representative. Restrictions may apply to certain accounts and transactions. Further details about breakpoint discounts can be found at www.franklintempleton.com, and in the SAI.

Additional reductions and waivers of sales charges. In addition to the breakpoint discount methods described above for class A shares, the fund may sell the classes of shares specified below without a sales charge or CDSC under the circumstances described below. The sales charge and CDSC waiver categories described below do not apply to customers purchasing shares of the fund through any of the financial intermediaries specified in Appendix A to this prospectus/information statement (each, a “Specified Intermediary”).

Different financial intermediaries may impose different sales charges. Please refer to Appendix A for the sales charge or CDSC waivers that are applicable to each Specified Intermediary.

Class A shares

The following categories of investors are eligible to purchase class A shares without payment of a sales charge:

Administrators and other service providers of employer-sponsored retirement plans are required to enter into contractual arrangements with Putnam Investor Services in order to offer and hold fund shares. Administrators and other service providers of employer-sponsored retirement plans seeking to place trades on behalf of their plan clients should consult Putnam Investor Services as to the applicable requirements.

Class A and class C shares

A CDSC is waived in the event of a redemption under the following circumstances:

Additional information about reductions and waivers of sales charges, including deferred sales charges, is included in the SAI. You may consult your financial representative or Franklin Distributors for assistance.

How do I sell or exchange fund shares? You can sell your shares back to the fund or exchange them for shares of another Putnam fund any day the NYSE is open, either through your financial representative or directly to the fund.

If you redeem your shares shortly after purchasing them, your redemption payment for the shares may be delayed until the fund collects the purchase price of the shares, which may be up to 7 calendar days after the purchase date.

Regarding exchanges, not all Putnam funds offer all classes of shares or may be open to new investors. If you exchange shares otherwise subject to a deferred sales charge, the transaction will not be subject to the deferred sales charge. When you redeem the shares acquired through the exchange, however, the redemption may be subject to the deferred sales charge, depending upon when and from which fund you originally purchased the shares. The deferred sales charge will be computed using the schedule of any fund into or from which you have exchanged your shares that would result in your paying the highest deferred sales charge applicable to your class of shares. For purposes of computing the deferred sales charge, the length of time you have owned your shares will be measured from the date of original purchase, unless you originally purchased the shares from another Putnam fund that does not directly charge a deferred sales charge, in which case the length of time you have owned your shares will be measured from the date you exchange those shares for shares of another Putnam fund that does charge a deferred sales charge, and will not be affected by any subsequent exchanges among funds.

Selling or exchanging shares through your financial representative. Your representative must receive your request in proper form before the close of regular trading on the NYSE for you to receive that day’s NAV, less any applicable deferred sales charge. Your representative will be responsible for furnishing all necessary documents to Putnam Investor Services on a timely basis and may charge you for his or her services.

Selling or exchanging shares directly with the fund. Putnam Investor Services must receive your request in proper form before the close of regular trading on the NYSE in order to receive that day’s NAV, less any applicable deferred sales charge.

By mail. Send a letter of instruction signed by all registered owners or their legal representatives to Putnam Investor Services.

By telephone. You may use Putnam’s telephone redemption privilege to redeem shares valued at less than $250,000 unless you have notified Putnam Investor Services of an address change within the preceding 15 days, in which case other requirements may apply. Unless you indicate otherwise on the account application, Putnam Investor Services will be authorized to accept redemption instructions received by telephone. A telephone exchange privilege is currently available. The telephone redemption and exchange privileges may be modified or terminated without notice.

Via the Internet. You may also exchange shares via the Internet at www.franklintempleton.com.

Shares held through your employer’s retirement plan. For information on how to sell or exchange shares of the fund that were purchased through your employer’s retirement plan, including any restrictions and charges that the plan may impose, please consult your employer.

Additional requirements. In certain situations, for example, if you sell shares with a value of $250,000 or more, the signatures of all registered owners or their legal representatives must be guaranteed by a bank, broker-dealer or certain other financial institutions. In addition, Putnam Investor Services usually requires additional documents for the sale of shares by a corporation, partnership, agent or fiduciary, or surviving joint owner. For more information concerning Putnam’s signature guarantee and documentation requirements, contact Putnam Investor Services.

The fund also reserves the right to revise or terminate the exchange privilege, limit the amount or number of exchanges or reject any exchange. The fund into which you would like to exchange may also reject your exchange. These actions may apply to all shareholders or only to those shareholders whose exchanges the Investment Manager determines are likely to have a negative effect on the fund or other Putnam funds. Consult Putnam Investor Services before requesting an exchange. Ask your financial representative or Putnam Investor Services for prospectuses of other Putnam funds. Some Putnam funds are not available in all states.

Deferred sales charges for class C and certain class A shares

A deferred sales charge of 1.00% will apply to class C shares if redeemed within one year of purchase. Class A shares that are part of a purchase of $500,000 or more (other than by an employer-sponsored retirement plan) will be subject to a 1.00% deferred sales charge if redeemed within twelve months of purchase.

Deferred sales charges will be based on the lower of the shares’ cost and current NAV. Shares not subject to any charge will be redeemed first, followed by shares held longest. You may sell shares acquired by reinvestment of distributions without a charge at any time.

Payment information. If your account is held directly with Putnam Investor Services, the fund typically expects to send you payment for your shares the business day after your request is received in good order. If you hold your shares through certain financial intermediaries or financial intermediary programs, receipt of payment for your shares may differ based on industry standard trade settlement practices, as managed by your intermediary. However, it is possible that payment of redemption proceeds, for both accounts held with Putnam Investor Services and those held through a financial intermediary, may take up to seven days. Under unusual circumstances, the fund may suspend redemptions, or postpone payment for more than seven days, as permitted by federal securities law. Under normal market conditions, the fund typically expects to satisfy redemption requests by using holdings of cash and cash equivalents or selling portfolio assets to generate cash. Under stressed market conditions, the fund may also satisfy redemption requests by borrowing under the fund’s interfund lending arrangements. For additional information regarding the fund’s interfund lending arrangements, please see the SAI.

To the extent consistent with applicable laws and regulations, the fund reserves the right to satisfy all or a portion of a redemption request by distributing securities or other property in lieu of cash (“in-kind” redemptions), under both normal and stressed market conditions. The fund generally expects to use in-kind redemptions only in stressed market conditions or stressed conditions specific to the fund, such as redemption requests that represent a large percentage of the fund’s net assets in order to minimize the effect of the large redemption on the fund and its remaining shareholders. The fund will not use in-kind redemptions for retail investors who hold shares of the fund through a financial intermediary. Any in-kind redemption will be effected through a pro rata distribution of all publicly traded portfolio securities or securities for which quoted bid prices are available, subject to certain exceptions. The securities distributed in an in-kind redemption will be valued in the same manner as they are valued for purposes of computing the fund’s net asset value.

Once distributed in-kind to an investor, securities may increase or decrease in value before the investor is able to convert them into cash. Any transaction costs or other expenses involved in liquidating securities received in an in- kind redemption will be borne by the redeeming investor. The fund has committed, in connection with an election under Rule 18f-1 under the Investment Company Act of 1940, to pay all redemptions of fund shares by a single shareholder during any 90-day period in cash, up to the lesser of (i) $250,000 or (ii) 1% of the fund’s net assets measured as of the beginning of such 90-day period. For information regarding procedures for in-kind redemptions, please contact Franklin Distributors. You will not receive interest on uncashed redemption checks.

Redemption by the fund. If you own fewer shares than the minimum set by the Trustees (presently 20 shares), the fund may redeem your shares without your permission and send you the proceeds after providing you with at least 60 days’ notice to attain the minimum. To the extent permitted by applicable law, the fund may also redeem shares if you own more than a maximum amount set by the Trustees. There is presently no maximum, but the Trustees could set a maximum that would apply to both present and future shareholders.

Abandoned property. If your account is held directly with Putnam Investor Services and is later deemed “abandoned” or “unclaimed” under state law, the fund may be required to “escheat” (transfer) the shares in your account, or to redeem those shares and remit the proceeds, to the applicable state’s unclaimed property division. The state may redeem escheated shares. If you subsequently seek to reclaim from the state the proceeds of any sale of your shares, you may only be able to recover the amount received when the shares were sold (and not the amount those shares are worth currently). It is your responsibility to maintain a correct address for your account, to keep your account active by contacting Putnam Investor Services by mail, by telephone or at www.franklintempleton.com, and to cash promptly all checks for dividends, capital gains and redemptions. The fund and Putnam Investor Services, the Investment Manager, and their respective affiliates will not be liable to fund shareholders or their representatives for good faith efforts to comply with state escheatment laws. For IRA accounts escheated to a state under these abandoned property laws, the escheatment will generally be treated as a taxable distribution to you; federal and any applicable state income tax will be withheld.

Policy on excessive short-term trading

Because the fund invests in underlying funds that invest in foreign securities, its performance may be adversely impacted and the interests of longer-term shareholders may be diluted as a result of time-zone arbitrage, a short- term trading practice that seeks to exploit changes in the value of the fund’s investments that result from events occurring after the close of the foreign markets on which the investments trade, but prior to the later close of trading on the NYSE, the time as of which the fund determines its NAV. If an arbitrageur is successful, he or she may dilute the interests of other shareholders by trading shares at prices that do not fully reflect their fair value.

When an underlying fund invests in securities that may trade infrequently or may be more difficult to value, such as lower-rated bonds and securities of smaller companies, it may be susceptible to trading by short-term traders who seek to exploit perceived price inefficiencies in the fund’s investments. In addition, the market for these securities may at times show “market momentum,” in which positive or negative performance may continue from one day to the next for reasons unrelated to the fundamentals of the issuer. Short-term traders may seek to capture this momentum by trading frequently in the fund’s shares, which will reduce the fund’s performance and may dilute the interests of other shareholders. Because lower-rated debt and securities of smaller companies may be less liquid than higher- rated debt or securities of larger companies, respectively, an underlying fund may also be unable to buy or sell these securities at desirable prices when the need arises (for example, in response to volatile cash flows caused by short- term trading). Similar risks may apply if the fund holds other types of less liquid securities.

The fund may be adversely affected if an underlying fund in which it invests is harmed by excessive short-term trading.

In particular, many purchase, redemption and exchange orders are received from financial intermediaries that hold omnibus accounts with the fund. Omnibus accounts are accounts in which shares are held in the name of a financial intermediary, such as a retirement plan sponsor, broker, adviser, or third-party administrator or recordkeeper, on behalf of its clients or participants, who are the beneficial owners of the fund shares held in the omnibus account.

The Investment Manager monitors cash flows into and out of the fund on an ongoing basis. If cash flows or other information indicate that excessive short-term trading may be taking place within an omnibus account, the Investment Manager will contact the financial intermediary that maintains the omnibus account to obtain information about trading activity of the beneficial owners and attempt to identify and remedy any excessive trading. However, the Investment Manager’s ability to monitor and deter excessive short-term traders in omnibus accounts ultimately depends on the capabilities and cooperation of the financial intermediaries that maintain the omnibus accounts.

Financial intermediaries may impose different or additional limits on short-term trading.

Distribution plans and payments to dealers. Putnam funds are distributed primarily through dealers (including any broker, dealer, bank, bank trust department, registered investment advisor, financial planner, retirement plan administrator, and any other institution having a selling, services, or any similar agreement with Franklin Distributors or one of its affiliates). In order to pay for the marketing of fund shares and services provided to shareholders, the fund has adopted distribution and service (12b-1) plans, which increase the annual operating expenses you pay each year in certain share classes, as shown in the tables of annual fund operating expenses in the section Fund summaries — Fees and expenses. Franklin Distributors and its affiliates also make additional payments to dealers that do not increase your fund expenses, as described below.

Franklin Distributors and its affiliates also pay additional compensation to selected dealers in recognition of their marketing support and/or program servicing (each of which is described in more detail below). These payments may create an incentive for a dealer firm or its representatives to recommend or offer shares of the fund or other Putnam funds to its customers. These additional payments are made by Franklin Distributors and its affiliates and do not increase the amount paid by you or the fund as shown under Fund summaries — Fees and expenses.

The additional payments to dealers by Franklin Distributors and its affiliates are generally based on one or more of the following factors: average net assets of the fund attributable to that dealer, sales or net sales of the fund attributable to that dealer, or reimbursement of ticket charges (fees that a dealer firm charges its representatives for effecting transactions in fund shares), or on the basis of a negotiated lump sum payment for services provided.

Marketing support payments are generally available to most dealers engaging in significant sales of Putnam fund shares. These payments are individually negotiated with each dealer firm, taking into account the marketing support services provided by the dealer, including business planning assistance, educating dealer personnel about the Putnam funds and shareholder financial planning needs, placement on the dealer’s preferred or recommended fund company list, access to sales meetings, sales representatives and management representatives of the dealer, market data, as well as the size of the dealer’s relationship with Franklin Distributors. Although the total amount of marketing support payments made to dealers in any year may vary, on average, the aggregate payments are not expected, on an annual basis, to exceed 0.085% of the average net assets of Putnam’s retail mutual funds attributable to the dealers.

Program servicing payments, which are paid in some instances to dealers in connection with investments in the fund through dealer platforms, and other investment programs, are not expected, with certain limited exceptions, to exceed 0.20% of the total assets in the program on an annual basis. These payments are made for program or platform services provided by the dealer, including shareholder recordkeeping, reporting, or transaction processing, as well as services rendered in connection with dealer platform development and maintenance, fund/investment selection and monitoring, or other similar services.

You can find a list of all dealers to which Franklin Distributors and its affiliates made marketing support and/or program servicing payments in 2023 in the SAI, which is on file with the SEC and is also available at www.franklintempleton.com. You can also find other details in the SAI about the payments made by Franklin Distributors and its affiliates and the services provided by your dealer. Your dealer may charge you fees or commissions in addition to those disclosed in this prospectus/information statement. You can also ask your dealer about any payments it receives from Franklin Distributors and its affiliates and any services your dealer provides, as well as about fees and/or commissions it charges.

Fund distributions and taxes. The fund declares a dividend monthly based on our projections of its estimated net income and normally distributes any net investment income monthly and any net realized capital gains annually.

You may choose to reinvest distributions from net investment income, capital gains or both in additional shares of your fund or other Putnam funds, or you may receive them in cash in the form of a check or an electronic deposit to your bank account. If you do not select an option when you open your account, all distributions will be reinvested. If you choose to receive distributions in cash, but correspondence from the fund or Putnam Investor Services is returned as “undeliverable,” the distribution option on your account may be converted to reinvest future distributions in the fund. You will not receive interest on uncashed distribution checks.

For shares purchased through your employer’s retirement plan, the terms of the plan will govern how the plan may receive distributions from the fund.

The fund’s investments in underlying funds could affect the amount, timing and character of distributions from the fund, and therefore, may increase the amount of taxes payable by shareholders.

For federal income tax purposes, distributions of net investment income are generally taxable to you as ordinary income. Taxes on distributions of capital gains are determined by how long the fund owned (or is deemed to have owned) the investments that generated them, rather than by how long you have owned (or are deemed to have owned) your shares. Distributions that the fund properly reports to you as gains from investments that the fund owned for more than one year are generally taxable to you as long-term capital gains includible in net capital gain and taxed to individuals at reduced rates. Distributions of gains from investments that the fund owned for one year or less and gains on the sale of or payment on bonds characterized as market discount are generally taxable to you as ordinary income. Distributions that the fund properly reports to you as “qualified dividend income” are taxable at the reduced rates applicable to your net capital gain provided that both you and the fund meet certain holding period and other requirements. Distributions are taxable in the manner described in this paragraph whether you receive them in cash or reinvest them in additional shares of the fund or other Putnam funds.

Distributions by the fund to retirement plans that qualify for tax-advantaged treatment under federal income tax laws will not be taxable. Special tax rules apply to investments through such plans. You should consult your tax advisor to determine the suitability of the fund as an investment through such a plan and the tax treatment of distributions (including distributions of amounts attributable to an investment in the fund) from such a plan.

Unless you are investing through a tax-advantaged retirement account (such as an IRA), you should consider avoiding a purchase of fund shares shortly before the fund makes a distribution because doing so may cost you money in taxes. Distributions are taxable to you even if they are paid from income or gains earned by the fund before your investment (and thus were included in the price you paid). Contact your financial representative or Putnam to find out the distribution schedule for your fund.

An underlying fund’s investments in foreign securities, if any, may be subject to foreign withholding or other taxes. In that case, the fund’s return on its investment in such underlying fund would be decreased. The fund may be entitled to elect to pass through to its shareholders a credit or deduction for foreign taxes (if any) borne with respect to foreign securities income earned by the fund or by any underlying funds and passed through to the fund. If the fund so elects, shareholders will include in gross income from foreign sources their pro rata shares of such taxes, if any, treated as paid by the fund. However, even if the fund elects to pass through to its shareholders foreign tax credits or deductions, tax-exempt shareholders and those who invest in the fund through tax-advantaged accounts such as IRAs will not benefit from any such tax credit or deduction.

Any gain resulting from the sale or exchange of your shares generally also will be subject to tax.

The above is a general summary of the tax implications of investing in the fund. Please refer to the SAI for further details. You should consult your tax advisor for more information on your own tax situation, including possible foreign, state and local taxes.

V. Other Information

Share Ownership.

Putnam Sustainable Retirement 2025 Fund

At May 23, 2025, the officers and Trustees of the fund as a group owned less than 1% of the outstanding shares of each class of the fund, and, except as noted below, no person owned of record or to the knowledge of a fund beneficially 5% or more of any class of shares of such fund.

Putnam Sustainable Retirement Maturity Fund

At May 23, 2025, the officers and Trustees of the fund as a group owned less than 1% of the outstanding shares of each class of the fund, and, except as noted below, no person owned of record or to the knowledge of a fund beneficially 5% or more of any class of shares of such fund.

Duplicate mailings. As permitted by SEC rules, the Investment Manager’s policy is to send a single copy of the prospectus to shareholders who share the same last name and address, unless a shareholder previously has requested otherwise. If you would prefer to receive your own copy of the prospectus, please contact Putnam Investor Services by phone at 1-800-225-1581 or by mail at P.O. Box 219697, Kansas City, MO 64121-9697.

Financial information. You may get free copies of each fund’s annual report, request other information about any Putnam fund, or make shareholder inquiries, by contacting your financial representative, by visiting Putnam’s website at putnam.com/individual, or by calling Putnam toll-free at 1-800-225-1581. You may access reports and other information about each fund on the EDGAR Database on the Securities and Exchange Commission’s website at http://www.sec.gov. You may get copies of this information, with payment of a duplication fee, by electronic request at the following E-mail address: publicinfo@sec.gov. You may need to refer to the fund’s file number.

WE ARE NOT ASKING YOU FOR A PROXY AND YOU ARE REQUESTED NOT TO SEND US A PROXY

Appendix A

Financial intermediary specific sales charge waiver information

As described in the prospectus, class A shares may be subject to an initial sales charge and class C shares may be subject to a CDSC. Certain financial intermediaries may impose different initial sales charges or waive the initial sales charge or CDSC in certain circumstances. This Appendix details the variations in sales charge waivers by financial intermediary. Not all financial intermediaries specify financial intermediary- specific sales charge waiver categories for every share class. For information about sales charges and waivers available for share classes other than those listed below, please see the section “Additional reductions and waivers of sales charges” in the prospectus. You should consult your financial representative for assistance in determining whether you may qualify for a particular sales charge waiver.

AMERIPRISE FINANCIAL

Front-End sales charge waivers on Class A shares available at Ameriprise Financial

The following information applies to class A share purchases if you have an account with or otherwise purchase fund shares through Ameriprise Financial:

Shareholders purchasing fund shares through an Ameriprise Financial account are eligible for the following front-end sales charge waivers, which may differ from those disclosed elsewhere in this fund’s prospectus or SAI:

D.A. Davidson & Co. (D.A.Davidson)

Shareholders purchasing fund shares including existing fund shareholders through a D.A. Davidson platform or account, or through an introducing broker-dealer or independent registered investment advisor for which D.A. Davidson provides trade execution, clearance, and/or custody services, will be eligible for the following sales charge waivers (front-end sales charge waivers and contingent deferred, or back-end, sales charge waivers) and discounts, which may differ from those disclosed elsewhere in this prospectus or SAI.

Front-End sales charge waivers on Class A shares available at D.A. Davidson

CDSC Waivers on Classes A and C shares available at D.A. Davidson

EDWARD D. JONES & CO., L. P. (“EDWARD JONES”)

Policies Regarding Transactions Through Edward Jones

The following information has been provided by Edward Jones:

Effective on or after September 3, 2024, the following information supersedes prior information with respect to transactions and positions held in fund shares through an Edward Jones system. Clients of Edward Jones (also referred to as “shareholders”) purchasing fund shares on the Edward Jones commission and fee-based platforms are eligible only for the following sales charge discounts (also referred to as “breakpoints”) and waivers, which can differ from discounts and waivers described elsewhere in the mutual fund prospectus or statement of additional information (“SAI”) or through another broker-dealer. In all instances, it is the shareholder’s responsibility to inform Edward Jones at the time of purchase of any relationship, holdings of the Putnam funds, or other facts qualifying the purchaser for discounts or waivers. Edward Jones can ask for documentation of such circumstance. Shareholders should contact Edward Jones if they have questions regarding their eligibility for these discounts and waivers.

Breakpoints

Rights of Accumulation (“ROA”)

Letter of Intent (“LOI”)

Sales Charge Waivers

Sales charges are waived for the following shareholders and in the following situations:

Contingent Deferred Sales Charge (“CDSC”) Waivers

If the shareholder purchases shares that are subject to a CDSC and those shares are redeemed before the CDSC is expired, the shareholder is responsible to pay the CDSC except in the following conditions:

Other Important Information Regarding Transactions Through Edward Jones

Minimum Purchase Amounts

Minimum Balances

Exchanging Share Classes

J.P. MORGAN SECURITIES LLC

Effective September 29, 2023, if you purchase or hold fund shares through an applicable J.P. Morgan Securities LLC brokerage account, you will be eligible for the following sales charge waivers (front-end sales charge waivers and contingent deferred sales charge (“CDSC”), or back-end sales charge, waivers), share class conversion policy and discounts, which may differ from those disclosed elsewhere in this fund’s prospectus or Statement of Additional Information (“SAI”).

Front-end sales charge waivers on Class A shares available at J.P. Morgan Securities LLC

Class C to Class A share conversion

CDSC waivers on Class A and C Shares available at J.P. Morgan Securities LLC

Shares sold upon the death or disability of the shareholder.

Shares sold as part of a systematic withdrawal plan as described in this prospectus. Shares purchased in connection with a return of excess contributions from an IRA account.

Shares sold as part of a required minimum distribution for IRA and retirement accounts pursuant to the Internal Revenue Code. Shares acquired through a right of reinstatement.

Front-end load discounts available at J.P. Morgan Securities LLC: breakpoints, rights of accumulation & letters of intent

Breakpoints as described in this prospectus.

JANNEY MONTGOMERY SCOTT LLC (“JANNEY”)

Effective May 1, 2020, if you purchase fund shares through a Janney brokerage account, you will be eligible for the following load waivers (front- end sales charge waivers and contingent deferred sales charge (“CDSC”), or back-end sales charge, waivers) and discounts, which may differ from those disclosed elsewhere in this fund’s Prospectus or SAI.

Front-end sales charge* waivers on Class A shares available at Janney

CDSC waivers on Class A and C shares available at Janney

Front-end sales charge* discounts available at Janney: breakpoints, rights of accumulation, and/or letters of intent

MERRILL LYNCH

Purchases or sales of front-end (i.e., Class A) or level-load (i.e., Class C) mutual fund shares through a Merrill platform or account will be eligible only for the following sales load waivers (front-end, contingent deferred, or back-end waivers) and discounts, which may differ from those disclosed elsewhere in this fund’s prospectus or SAI. Purchasers will have to buy mutual fund shares directly from the mutual fund company or through another intermediary to be eligible for waivers or discounts not listed below.

It is the client’s responsibility to notify Merrill at the time of purchase or sale of any relationship or other facts that qualify the transaction for a waiver or discount. A Merrill representative may ask for reasonable documentation of such facts and Merrill may condition the granting of a waiver or discount on the timely receipt of such documentation.

Additional information on waivers and discounts is available in the Merrill Sales Load Waiver and Discounts Supplement (the “Merrill SLWD Supplement”) and in the Mutual Fund Investing at Merrill pamphlet at ml.com/funds. Clients are encouraged to review these documents and speak with their financial advisor to determine whether a transaction is eligible for a waiver or discount.

Front-end Sales Load Waivers Available at Merrill

Contingent Deferred Sales Charge (“CDSC”) Waivers on Front-end, Back-end, and Level Load Shares Available at Merrill

Front-end Sales Load Discounts Available at Merrill: Breakpoints, Rights of Accumulation & Letters of Intent

MORGAN STANLEY WEALTH MANAGEMENT

Effective July 1, 2018, shareholders purchasing fund shares through a Morgan Stanley Wealth Management transactional brokerage account will be eligible only for the following front-end sales charge waivers with respect to class A shares, which may differ from and may be more limited than those disclosed elsewhere in this fund’s Prospectus or SAI.

Front-end sales charge waivers on class A shares available at Morgan Stanley Wealth Management:

OPPENHEIMER & CO. INC. (“OPCO”)

Effective September 1, 2020, shareholders purchasing Fund shares through an OPCO platform or account are eligible only for the following load waivers (front-end sales charge waivers and contingent deferred, or back-end, sales charge waivers) and discounts, which may differ from those disclosed elsewhere in this Fund’s prospectus or SAI.

Front-end sales load waivers on Class A shares available at OPCO

CDSC waivers on A, B and C shares available at OPCO

Front-end sales charge discounts available at OPCO: breakpoints & rights of accumulation

RAYMOND JAMES & ASSOCIATES, INC., RAYMOND JAMES FINANCIAL SERVICES, INC. AND EACH ENTITY’S AFFILIATES (“RAYMOND JAMES”)

Effective March 1, 2019, shareholders purchasing fund shares through a Raymond James platform or account, or through an introducing broker- dealer or independent registered investment adviser for which Raymond James provides trade execution, clearance, and/or custody services, will be eligible only for the following load waivers (front-end sales charge waivers and contingent deferred, or back-end, sales charge waivers) and discounts, which may differ from those disclosed elsewhere in this fund’s prospectus or SAI.

Front-end sales load waivers on Class A shares available at Raymond James

CDSC waivers on Classes A, B and C shares available at Raymond James

Front-end load discounts available at Raymond James: breakpoints, rights of accumulation, and/or letters of intent

ROBERT W. BAIRD & CO. (“BAIRD”)

Effective September 1, 2020, shareholders purchasing fund shares through a Baird brokerage account will only be eligible for the following sales charge waivers (front-end sales charge waivers and CDSC waivers) and discounts, which may differ from those disclosed elsewhere in this prospectus or the SAI.

Front-End sales charge waivers on Class A shares available at Baird

CDSC waivers on Class A and C shares available at Baird

Front-End sales charge discounts available at Baird: breakpoints and/or rights of accumulation

STIFEL, NICOLAUS & COMPANY, INCORPORATED (“STIFEL”)

Effective September 1, 2020, shareholders purchasing Fund shares through a Stifel platform or account or who own shares for which Stifel or an affiliate is the broker-dealer of record are eligible for the following additional sales charge waiver.

Front-end Sales Charge Waiver on Class A Shares

Class A sales charge waivers available only through specified intermediaries

As described in the prospectus, class A shares may be purchased at net asset value without payment of a sales charge through a broker-dealer, financial institution, or financial intermediary that has entered into an agreement with Franklin Distributors to offer shares through a retail self- directed brokerage account with or without the imposition of a transaction fee.

The following intermediaries have entered into such an agreement:

National Financial Services LLC

Charles Schwab & Co., Inc.

Merrill Lynch, Pierce, Fenner & Smith Incorporated

J.P. Morgan Securities LLC

TD Ameritrade, Inc. and TD Ameritrade Clearing, Inc.

Morgan Stanley Smith Barney LLC

Interactive Brokers LLC

Vanguard Marketing Corporation

Citigroup Global Markets Inc.

E*Trade Securities LLC

This Statement of Additional Information (“SAI”) contains additional information to that included in the Prospectus of Putnam Sustainable Retirement Maturity Fund dated June 10, 2025 (the “Prospectus”) relating to the sale of all or substantially all of the assets of Putnam Sustainable Retirement 2025 Fund to Putnam Sustainable Retirement Maturity Fund. An unaudited narrative description of the pro forma effects of the reorganization of Putnam Sustainable Retirement 2025 Fund into Putnam Sustainable Retirement Maturity Fund for the twelve-month period ended July 31, 2024 is included in this SAI. Putnam Sustainable Retirement Maturity Fund’s Statement of Additional Information dated November 30, 2024, as supplemented, is attached to this SAI as an Appendix. This SAI is not a prospectus and is authorized for distribution only when it accompanies or follows delivery of the Prospectus. This SAI should be read in conjunction with the Prospectus. For a free copy of the prospectus, call Putnam Investor Services at 1-800-225-1581 or write P.O. Box 219697, Kansas City, MO 64121-9697 or visit www.franklintempleton.com.

The Statement of Additional Information of Putnam Sustainable Retirement Maturity Fund dated November 30, 2024, as supplemented (the “Acquiring Fund SAI”), which has been filed with the Securities and Exchange Commission, is included as the Appendix to this SAI. The information regarding Putnam Sustainable Retirement Maturity Fund contained in the Acquiring Fund SAI is hereby incorporated by reference into this SAI.

The table below shows the value of each Trustee's holdings in the fund and in all of the Putnam Funds as of December 31, 2024.

The following table shows the year each Trustee was first elected a Trustee of the Putnam funds, the fees paid to each Trustee by the fund for fiscal 2024, and the fees paid to each Trustee by all of the Putnam funds for services rendered during calendar year 2024:

¹ Estimated benefits for each Trustee are based on Trustee fee rates for calendar years 2003, 2004 and 2005.

² Mr. Leibler retired from the Board of Trustees effective June 30, 2024.

³ Mr. McGreevey was appointed to the Board of Trustees on May 17, 2024.

⁴ Mr. Reynolds and Ms. Trust are not compensated by the Fund for their service as Trustees because of their affiliation with the Investment Manager.

⁵ Ms. Trust was appointed to the Board of Trustees on January 26, 2024.

SHARE OWNERSHIP

Putnam Sustainable Retirement Maturity Fund

At May 23, 2025, the officers and Trustees of the fund as a group owned less than 1% of the outstanding shares of each class of the fund, and, except as noted below, no person owned of record or to the knowledge of a fund beneficially 5% or more of any class of shares of such fund.

INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

PricewaterhouseCoopers LLP, 101 Seaport Boulevard, Boston, Massachusetts 02210, is the fund’s independent registered public accounting firm providing audit services, tax return review and other tax consulting services and assistance and consultation in connection with the review of various Securities and Exchange Commission filings.

The following documents are incorporated by reference into this SAI: (i) Report of Independent Registered Public Accounting Firm, financial highlights and financial statements included in Putnam Sustainable Retirement Maturity Fund’s Annual Report to shareholders for the fiscal year ended July 31, 2024, and (ii) Report of Independent Registered Public Accounting Firm, financial highlights and financial statements included in Putnam Sustainable Retirement 2025 Fund’s Annual Report to shareholders for the fiscal year ended July 31, 2024. The audited financial statements for Putnam Sustainable Retirement Maturity Fund, and Putnam Sustainable Retirement 2025 Fund incorporated by reference into the Prospectus and SAI have been so included and incorporated in reliance upon the reports of the independent registered public accounting firm, given on their authority as experts in auditing and accounting.

Pro forma financial statements of Putnam Sustainable Retirement 2025 Fund and Putnam Sustainable Retirement Maturity Fund

NARRATIVE DESCRIPTION OF THE PRO FORMA EFFECTS OF THE REORGANIZATION

The unaudited pro forma information set forth below for the six month period ended on January 31, 2025 is intended to present supplemental data as if the reorganization of Putnam Sustainable Retirement 2025 Fund (the “Selling Fund”) into Putnam Sustainable Retirement Maturity Fund (the “Acquiring Fund,” and together with the Selling Fund, each a “Fund” and collectively, the “Funds”) (the “Reorganization”), had occurred as of the beginning of the period (unless otherwise noted).

Basis of Combination

In April 2025, the Board of Trustees of the Selling Fund approved an Agreement and Plan of Reorganization (the “Agreement”) pursuant to which the Selling Fund will transfer all of its assets to the Acquiring Fund in exchange for shares of the Acquiring Fund (“Merger Shares”) and the assumption by that Acquiring Fund of the Selling Fund’s liabilities. The Selling Fund and the Acquiring Fund offer Class A Class C, Class R3, Class R4, Class R5, Class R6, and Class Y shares. Selling Fund shareholders of each class will receive the same class of Merger Shares as indicated in Table 1 below. The Acquiring Fund will issue Merger Shares with an aggregate net asset value equal to the aggregate value of the assets that it receives from the Selling Fund, less the liabilities it assumes from the Selling Fund and any expenses of the Reorganization payable by the Selling Fund. No shareholders of the Selling Fund will pay any sales charges, commissions, or transaction fees in connection with acquiring Merger Shares. Immediately following the transfer, shareholders of each class of the Selling Fund will receive a proportional distribution of shares of the same class (as shown in Table 1) of the Acquiring Fund.

Table 1 – Merger Shares

Putnam Sustainable Retirement 2025 Fund		Putnam Sustainable Retirement Maturity Fund
Class A		Class A
Class C		Class C
Class R		Class R
Class R3		Class R3
Class R4		Class R4
Class R5		Class R5
Class R6		Class R6
Class Y		Class Y

The Reorganization is expected to be tax-free for U.S. federal income tax purposes. Accordingly, it is expected that Selling Fund shareholders will not, and the Selling Fund generally will not, recognize gain or loss as a direct result of the Reorganization. Following the Reorganization, the Acquiring Fund will be the accounting

successor of the Reorganization. In accordance with accounting principles generally accepted in the United States, the historical cost of investment securities will be carried forward to the Acquiring Fund and the results of operations for pre-Reorganization periods will not be restated. Franklin Advisers, Inc. (the “Investment Manager”) is expected to bear the direct merger costs, legal fees, audit fees, Form N-14 printing and mailing costs, as well as similar expenses incurred in connection with the consummation of the Reorganization and transaction costs (if any) associated with repositioning the Selling Fund prior to the Reorganization. The Selling Fund’s repositioning costs are discussed in the respective “Fees and Expenses” sub-section of its respective Information about the Merger  section of the Combined Information Statement/Prospectus. If the Reorganization is not consummated, the Investment Manager will bear the costs associated with the Reorganization. The pro forma information provided herein should be read in conjunction with the audited financial statements of each Fund included in its most recent annual report, in each case dated as of July 31, 2024, and, as applicable, the unaudited financial statements of each Fund included in its most recent semi-annual report, in each case dated as of January 31, 2025.

Table 2 below presents the net assets of each Fund as of January 31, 2025.

Table 2 – Selling Funds and Acquiring Funds’ Net Assets as of January 31, 2025

Table 3 presents the estimated Reorganization costs (exclusive of any transaction costs associated with any portfolio realignment); the net assets as of January 31, 2025 with respect to the Acquiring Fund assuming the Reorganization occurred on that date, after accounting for the estimated Reorganization costs to be borne by the Acquiring Fund and the Selling Fund; and, on a pro forma basis, the estimated relative increases or decreases in combined operating expenses that would have been incurred during the one-year period ended on January 31, 2025. The pro forma increases and decreases represent the differences between (i) the combined expenses actually charged to the Acquiring Fund and the Selling Fund during the period and (ii) the expenses that would have been charged to the Acquiring Fund and the Selling Fund, based on the combined assets of the Funds, if the Reorganization and any contractual changes had occurred at the beginning of the year.

The unaudited pro forma information set forth in Table 3 below reflects adjustments made to expenses for differences in contractual rates, duplicate services and other services that would not have occurred if the Reorganization had taken place on the first day of the period described above. The pro forma information has been derived from the books and records of the Funds utilized in calculating daily net asset value for the Funds and has been prepared in accordance with accounting principles generally accepted in the United States, which require the use of management estimates. Actual results could differ from those estimates.

Table 3 – Estimated Reorganization Costs, Combined Fund Net Assets and Pro Forma Increases or Decreases in Expenses⁽¹⁾

Management Fees (Combined Investment Management and Administration Fees)

Pursuant to a Management Agreement with the Investment Manager, each fund pays a management fee to the Investment Manager. The fee for each fund is calculated and paid monthly based on an annual rate and the fund’s average net assets for the month. The Acquiring Fund’s management fee schedule will apply following completion of the Reorganization. For Putnam Sustainable Retirement Maturity Fund, the annual rate is 0.46%. For Putnam Sustainable Retirement 2025 Fund, the annual rate is 0.47.

Putnam Investor Services, Inc. is the transfer agent for each Fund. Franklin Distributors, LLC, an affiliate of the Investment Manager, is the distributor for each Fund.

There will be no significant changes to accounting, valuation or tax policies as the result of the proposed Reorganization.

The estimated costs of the Reorganization shown in Table 3 above do not reflect any brokerage commissions incurred by a Fund in connection with any portfolio realignment.

Federal Income Taxes

Please see “Federal Income Tax Consequences” in the Combined Information Statement/Prospectus for a discussion of the tax effects of the Reorganization.

It is each Fund’s policy to comply with the requirements of the Internal Revenue Code of 1986, as amended, applicable to regulated investment companies and to eliminate a fund-level tax, and therefore to distribute at least annually all of its investment company taxable income (generally taxable ordinary income and the excess, if any, of net short-term capital gains over net long-term capital losses), its net-tax exempt interest income, if any, and its net realized capital gains, if any, to shareholders. After the Reorganization, the Acquiring Fund intends to continue to comply with these requirements to qualify as a regulated investment company that pays no fund-level tax.

APPENDIX

STATEMENT OF ADDITIONAL INFORMATION OF

PUTNAM TARGET DATE FUNDS

Schedule A

Putnam California Tax Exempt Income Fund
Putnam Dynamic Asset Allocation Growth Fund
George Putnam Balanced Fund
Putnam Research Fund
Putnam Strategic Intermediate Municipal Fund
Putnam Sustainable Retirement 2025 Fund
Putnam Sustainable Retirement 2065 Fund
Putnam Sustainable Retirement 2030 Fund
Putnam Sustainable Retirement 2035 Fund
Putnam Sustainable Retirement 2040 Fund
Putnam Sustainable Retirement 2045 Fund
Putnam Sustainable Retirement 2050 Fund
Putnam Sustainable Retirement 2055 Fund
Putnam Sustainable Retirement 2060 Fund
Putnam Sustainable Retirement Maturity Fund
Putnam Tax Exempt Income Fund
Putnam Tax-Free High Yield Fund
Putnam Ultra Short Duration Income Fund

Putnam Ultra Short MAC Series
Putnam VT Core Equity Fund

Putnam VT Diversified Income Fund
Putnam VT Emerging Markets Equity Fund
Putnam VT Focused International Equity Fund
Putnam VT George Putnam Balanced Fund
Putnam VT Global Asset Allocation Fund
Putnam VT Global Health Care Fund
Putnam VT High Yield Fund
Putnam VT Income Fund
Putnam VT International Equity Fund
Putnam VT International Value Fund
Putnam VT Large Cap Value Fund
Putnam VT Large Cap Growth Fund
Putnam VT Mortgage Securities Fund
Putnam VT Research Fund
Putnam VT Small Cap Growth Fund
Putnam VT Small Cap Value Fund
Putnam VT Sustainable Future Fund
Putnam VT Sustainable Leaders Fund

SUPPLEMENT DATED JANUARY 28, 2025

TO THE PROSPECTUS AND STATEMENT OF

ADDITIONAL INFORMATION (“SAI”)

OF EACH FUND LISTED IN SCHEDULE A

Effective January 31, 2025, the following changes are made to each fund’s Prospectus and SAI:

* Messrs. Fetch and Schoen are anticipated to retire and step down as members of the fund’s portfolio management team on or about March 31, 2025.

Berkeley Belknap

Portfolio Manager, portfolio manager of the fund since January 2025

Thomas A. Nelson, CFA

Portfolio Manager, portfolio manager of the fund since January 2025

Jonathan M. Schreiber, CFA

Portfolio Manager, portfolio manager of the fund since January 2025