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Fee Table The following table describes the fees and expenses that may be incurred when you buy, hold, and sell shares of the fund. Shareholder fees 0 Annual Operating Expenses 0.0000 0 0.0001 0.0001 -0.0001 0.0000 December 31, 2029 This example helps compare the cost of investing in the fund with the cost of investing in other funds. Let's say, hypothetically, that the annual return for shares of the fund is 5% and that the fees and the annual operating expenses for shares of the fund are exactly as described in the fee table. This example illustrates the effect of fees and expenses, but is not meant to suggest actual or expected fees and expenses or returns, all of which may vary. For every $10,000 you invested, here's how much you would pay in total expenses if you sell all of your shares at the end of each time period indicated: 0 0 2 9 Portfolio Turnover The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual operating expenses or in the example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 580 % of the average value of its portfolio. 5.80 Principal Investment Strategies Normally investing at least 80% of assets in investment-grade securitized debt securities (those of medium and high quality) and repurchase agreements for those securities. Securitized debt securities are interests in pools of mortgages, loans, receivables, or other assets, and include such instruments as mortgage-backed securities, commercial mortgage-backed securities, and other asset-backed securities that are issued by the U.S. Government, its agencies or instrumentalities, foreign governments, financial institutions, trusts and corporations. Payment of principal or interest on securitized debt instruments generally depends on the cash flows generated by the underlying assets and may be supported by letters of credit, surety bonds, or other credit enhancements. Investment grade securities in which the fund invests include securities or issuers rated at least BBB- or its equivalent by at least one nationally recognized statistical ratings organization (NRSRO), or, if unrated, determined by the Adviser to be of comparable quality. A repurchase agreement is an agreement to buy a security at one price and a simultaneous agreement to sell it back at an agreed-upon price. Derivative instruments that provide investment exposure to the investments above or exposure to one or more market risk factors associated with such investments are included in the fund's 80% policy, consistent with the fund's investment policies and limitations with respect to investments in derivatives. Investing in U.S. Government securities issued by entities that are chartered or sponsored by Congress but whose securities are neither issued nor guaranteed by the U.S. Treasury. Managing the fund to have similar overall interest rate risk to the Bloomberg U.S. Securitized Index. Allocating assets across different market sectors and maturities. Investing in domestic and foreign issuers. Analyzing the credit quality of the issuer, security-specific features, current and potential future valuation, and trading opportunities to select investments. Investing in lower-quality debt securities (those of less than investment-grade quality, also referred to as high yield debt securities or junk bonds). Engaging in transactions that have a leveraging effect on the fund, including investments in derivatives - such as swaps (interest rate, total return, and credit default), options, and futures contracts - and forward-settling securities, to adjust the fund's risk exposure. Interest Rate Changes. Interest rate increases can cause the price of a debt security to decrease. Foreign Exposure. Foreign markets can be more volatile than the U.S. market due to increased risks of adverse issuer, political, regulatory, market, or economic developments and can perform differently from the U.S. market. Securitized Debt Securities Exposure. Securitized debt securities are dependent on the cash flows generated by the underlying assets and can be significantly affected by changes in interest rates, the availability of information concerning the underlying assets and their structure, and the creditworthiness of the originators of the loans or other receivables or the entities providing credit support. Prepayment. The ability of an issuer of a debt security to repay principal prior to a security's maturity can cause greater price volatility if interest rates change. Issuer-Specific Changes. The value of an individual security or particular type of security can be more volatile than, and can perform differently from, the market as a whole. A decline in the credit quality of an issuer or a provider of credit support (such as guarantees) or a maturity-shortening structure (such as demand and put features) for a security can cause the price of a security to decrease. Lower-quality debt securities (those of less than investment-grade quality, also referred to as high yield debt securities or junk bonds) involve greater risk of default or price changes due to changes in the credit quality of the issuer. The value of lower-quality debt securities can be more volatile due to increased sensitivity to adverse issuer, political, regulatory, market, or economic developments. U.S. Government Obligations Risk. Certain securities in which the fund may invest, including securities issued by certain U.S. Government agencies and U.S. Government sponsored enterprises, are not guaranteed by the U.S. Government or supported by the full faith and credit of the United States. Leverage Risk. Leverage can increase market exposure, magnify investment risks, and cause losses to be realized more quickly. High Portfolio Turnover. High portfolio turnover (more than 100%) may result in increased transaction costs and potentially higher capital gains or losses. The effects of higher than normal portfolio turnover may adversely affect the fund's performance. An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency .   You could lose money by investing in the fund. Performance The following information is intended to help you understand the risks of investing in the fund. The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time. The additional index has characteristics relevant to the fund's investment strategies. Index descriptions appear in the "Additional Index Information" section of the prospectus. Past performance (before and after taxes) is not an indication of future performance. The performance shown does not reflect the impact of any fees paid at the fee-based account or plan level, if applicable. Visit www.fidelity.com for more recent performance information. The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time. Past performance (before and after taxes) is not an indication of future performance. www.fidelity.com Year-by-Year Returns 0.0668 0.0524 -0.0081 -0.1179 0.0564 0.0179 0.0874    Highest Quarter Return 0.0756 2023-12-31    Lowest Quarter Return -0.0517 2022-03-31    Year-to-Date Return -0.0261 2026-09-30 Average Annual Returns After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes. Actual after-tax returns may differ depending on your individual circumstances. The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan). Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares. After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes. The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan). Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares. Return Before Taxes 0.0874 0.0046 0.0210 Return After Taxes on Distributions 0.0678 -0.0082 0.0074 Return After Taxes on Distributions and Sale of Fund Shares 0.0513 -0.0020 0.0102 Bloomberg U.S. Securitized Index 0.0849 0.0022 0.0178 Bloomberg U.S. Aggregate Bond Index 0.0730 -0.0036 0.0204 2018-08-17 Fund Summary Fund /Class: Fidelity Advisor® Mortgage Securities Fund /Fidelity® Mortgage Securities Fund Investment Objective Fidelity Advisor® Mortgage Securities Fund seeks a high level of current income, consistent with prudent investment risk. In seeking current income, the fund may also consider the potential for capital gain. Fee Table The following table describes the fees and expenses that may be incurred when you buy, hold, and sell shares of the fund. You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and examples below. Shareholder fees 0 Annual Operating Expenses 0.0028 0 0.0017 0.0045 This example helps compare the cost of investing in the fund with the cost of investing in other funds. Let's say, hypothetically, that the annual return for shares of the fund is 5% and that the fees and the annual operating expenses for shares of the fund are exactly as described in the fee table. This example illustrates the effect of fees and expenses, but is not meant to suggest actual or expected fees and expenses or returns, all of which may vary. For every $10,000 you invested, here's how much you would pay in total expenses if you sell all of your shares at the end of each time period indicated: 46 144 252 567 Portfolio Turnover The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual operating expenses or in the example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 607 % of the average value of its portfolio. 6.07 Principal Investment Strategies Normally investing at least 80% of assets in investment-grade mortgage-related securities (those of medium and high quality) and repurchase agreements for those securities. Mortgage-related securities include mortgage-backed securities (MBS) such as residential mortgage-backed securities, commercial mortgage-backed securities, stripped mortgage-backed securities, collateralized mortgage obligations, inverse floating rate obligations, mortgage pass-through securities, and other similar types of securities representing an interest in or that are secured by pools of mortgages. Investment grade securities in which the fund invests include securities or issuers rated at least BBB- or its equivalent by at least one nationally recognized statistical ratings organization (NRSRO), or, if unrated, determined by the Adviser to be of comparable quality. A repurchase agreement is an agreement to buy a security at one price and a simultaneous agreement to sell it back at an agreed-upon price. Derivative instruments that provide investment exposure to the investments above or exposure to one or more market risk factors associated with such investments are included in the fund's 80% policy, consistent with the fund's investment policies and limitations with respect to investments in derivatives. Investing in U.S. Government securities and instruments related to U.S. Government securities. Investing in U.S. Government securities issued by entities that are chartered or sponsored by Congress but whose securities are neither issued nor guaranteed by the U.S. Treasury. Managing the fund to have similar overall interest rate risk to the Bloomberg U.S. MBS Index. Allocating assets across different market sectors and maturities. Analyzing the credit quality of the issuer, security-specific features, current and potential future valuation, and trading opportunities to select investments. Investing in lower-quality debt securities (those of less than investment-grade quality, also referred to as high yield debt securities or junk bonds). Engaging in transactions that have a leveraging effect on the fund, including investments in derivatives - such as swaps (interest rate, total return, and credit default), options, and futures contracts - and forward-settling securities, to adjust the fund's risk exposure. Interest Rate Changes. Interest rate increases can cause the price of a debt security to decrease. Prepayment. The ability of an issuer of a debt security to repay principal prior to a security's maturity can cause greater price volatility if interest rates change. Issuer-Specific Changes. The value of an individual security or particular type of security can be more volatile than, and can perform differently from, the market as a whole. A decline in the credit quality of an issuer or a provider of credit support (such as guarantees) or a maturity-shortening structure (such as demand and put features) for a security can cause the price of a security to decrease. Lower-quality debt securities (those of less than investment-grade quality, also referred to as high yield debt securities or junk bonds) involve greater risk of default or price changes due to changes in the credit quality of the issuer. The value of lower-quality debt securities can be more volatile due to increased sensitivity to adverse issuer, political, regulatory, market, or economic developments. U.S. Government Obligations Risk. Certain securities in which the fund may invest, including securities issued by certain U.S. Government agencies and U.S. Government sponsored enterprises, are not guaranteed by the U.S. Government or supported by the full faith and credit of the United States. Leverage Risk. Leverage can increase market exposure, magnify investment risks, and cause losses to be realized more quickly. High Portfolio Turnover. High portfolio turnover (more than 100%) may result in increased transaction costs and potentially higher capital gains or losses. The effects of higher than normal portfolio turnover may adversely affect the fund's performance. An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency .   You could lose money by investing in the fund. Performance The following information is intended to help you understand the risks of investing in the fund. The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time. The additional index has characteristics relevant to the fund's investment strategies. Index descriptions appear in the "Additional Index Information" section of the prospectus. Past performance (before and after taxes) is not an indication of future performance. Visit www.fidelity.com for more recent performance information. The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time. Past performance (before and after taxes) is not an indication of future performance. www.fidelity.com Year-by-Year Returns 0.0186 0.0234 0.0078 0.0641 0.0440 -0.0104 -0.1221 0.0490 0.0101 0.0827    Highest Quarter Return 0.0776 2023-12-31    Lowest Quarter Return -0.0546 2022-09-30    Year-to-Date Return -0.0304 2026-09-30 Average Annual Returns After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes. Actual after-tax returns may differ depending on your individual circumstances. The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan). Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares. After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes. The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan). Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares. Return Before Taxes 0.0827 -0.0007 0.0152 Return After Taxes on Distributions 0.0653 -0.0120 0.0042 Return After Taxes on Distributions and Sale of Fund Shares 0.0486 -0.0053 0.0069 Bloomberg U.S. MBS Index 0.0858 0.0015 0.0159 Bloomberg U.S. Aggregate Bond Index 0.0730 -0.0036 0.0201 Fund Summary Fund /Class: Fidelity Advisor® Mortgage Securities Fund /A, M, C, I, Z   Investment Objective Fidelity Advisor® Mortgage Securities Fund seeks a high level of current income, consistent with prudent investment risk. In seeking current income, the fund may also consider the potential for capital gain. Fee Table The following table describes the fees and expenses that may be incurred when you buy, hold, and sell shares of the fund. You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and examples below. You may qualify for sales charge discounts if you and your family invest, or agree to invest in the future, at least $ 50,000 in the fund or certain other Fidelity ® funds. More information about these and other discounts is available from your investment professional and in the "Fund Distribution" section beginning on page 34 of the prospectus and in the sales charge waiver appendix to the prospectus. You may qualify for sales charge discounts if you and your family invest, or agree to invest in the future, at least $ 50,000 in the fund or certain other Fidelity ® funds. More information about these and other discounts is available from your investment professional and in the "Fund Distribution" section beginning on page 34 of the prospectus 50000 Shareholder fees 0.0400 0.0400 0 0 0 0 0 0.0100 0 0 Class A and Class M purchases of $1 million or more will not be subject to a front-end sales charge. Such Class A and Class M purchases may be subject, upon redemption, to a contingent deferred sales charge (CDSC) of 0.75% and 0.25%, respectively. On Class C shares redeemed less than one year after purchase. Annual Operating Expenses 0.0028 0.0028 0.0028 0.0028 0.0028 0.0025 0.0025 0.0100 0 0 0.0026 0.0028 0.0032 0.0032 0.0012 0.0079 0.0081 0.0160 0.0060 0.0040 -0.0000 -0.0000 -0.0000 -0.0000 -0.0004 0.0079 0.0081 0.0160 0.0060 0.0036 2027-12-31 This example helps compare the cost of investing in the fund with the cost of investing in other funds. Let's say, hypothetically, that the annual return for shares of the fund is 5% and that the fees and the annual operating expenses for shares of the fund are exactly as described in the fee table. This example illustrates the effect of fees and expenses, but is not meant to suggest actual or expected fees and expenses or returns, all of which may vary. For every $10,000 you invested, here's how much you would pay in total expenses if you sell all of your shares at the end of each time period indicated and if you hold your shares: 477 477 479 479 263 163 61 61 37 37 642 642 648 648 505 505 192 192 123 123 821 821 832 832 871 871 335 335 219 219 1339 1339 1362 1362 1683 1683 750 750 500 500 Portfolio Turnover The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual operating expenses or in the example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 607 % of the average value of its portfolio. 6.07 Principal Investment Strategies Normally investing at least 80% of assets in investment-grade mortgage-related securities (those of medium and high quality) and repurchase agreements for those securities. Mortgage-related securities include mortgage-backed securities (MBS) such as residential mortgage-backed securities, commercial mortgage-backed securities, stripped mortgage-backed securities, collateralized mortgage obligations, inverse floating rate obligations, mortgage pass-through securities, and other similar types of securities representing an interest in or that are secured by pools of mortgages. Investment grade securities in which the fund invests include securities or issuers rated at least BBB- or its equivalent by at least one nationally recognized statistical ratings organization (NRSRO), or, if unrated, determined by the Adviser to be of comparable quality. A repurchase agreement is an agreement to buy a security at one price and a simultaneous agreement to sell it back at an agreed-upon price. Derivative instruments that provide investment exposure to the investments above or exposure to one or more market risk factors associated with such investments are included in the fund's 80% policy, consistent with the fund's investment policies and limitations with respect to investments in derivatives. Investing in U.S. Government securities and instruments related to U.S. Government securities. Investing in U.S. Government securities issued by entities that are chartered or sponsored by Congress but whose securities are neither issued nor guaranteed by the U.S. Treasury. Managing the fund to have similar overall interest rate risk to the Bloomberg U.S. MBS Index. Allocating assets across different market sectors and maturities. Analyzing the credit quality of the issuer, security-specific features, current and potential future valuation, and trading opportunities to select investments. Investing in lower-quality debt securities (those of less than investment-grade quality, also referred to as high yield debt securities or junk bonds). Engaging in transactions that have a leveraging effect on the fund, including investments in derivatives - such as swaps (interest rate, total return, and credit default), options, and futures contracts - and forward-settling securities, to adjust the fund's risk exposure. Interest Rate Changes. Interest rate increases can cause the price of a debt security to decrease. Prepayment. The ability of an issuer of a debt security to repay principal prior to a security's maturity can cause greater price volatility if interest rates change. Issuer-Specific Changes. The value of an individual security or particular type of security can be more volatile than, and can perform differently from, the market as a whole. A decline in the credit quality of an issuer or a provider of credit support (such as guarantees) or a maturity-shortening structure (such as demand and put features) for a security can cause the price of a security to decrease. Lower-quality debt securities (those of less than investment-grade quality, also referred to as high yield debt securities or junk bonds) involve greater risk of default or price changes due to changes in the credit quality of the issuer. The value of lower-quality debt securities can be more volatile due to increased sensitivity to adverse issuer, political, regulatory, market, or economic developments. U.S. Government Obligations Risk. Certain securities in which the fund may invest, including securities issued by certain U.S. Government agencies and U.S. Government sponsored enterprises, are not guaranteed by the U.S. Government or supported by the full faith and credit of the United States. Leverage Risk. Leverage can increase market exposure, magnify investment risks, and cause losses to be realized more quickly. High Portfolio Turnover. High portfolio turnover (more than 100%) may result in increased transaction costs and potentially higher capital gains or losses. The effects of higher than normal portfolio turnover may adversely affect the fund's performance. An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency .   You could lose money by investing in the fund. Performance The following information is intended to help you understand the risks of investing in the fund. The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time. The additional index has characteristics relevant to the fund's investment strategies. Index descriptions appear in the "Additional Index Information" section of the prospectus. Past performance (before and after taxes) is not an indication of future performance. Visit institutional.fidelity.com for more recent performance information. The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time. Past performance (before and after taxes) is not an indication of future performance. institutional.fidelity.com Year-by-Year Returns The returns in the bar chart do not reflect any applicable sales charges; if sales charges were reflected, returns would be lower than those shown. The returns in the bar chart do not reflect any applicable sales charges; if sales charges were reflected, returns would be lower than those shown. 0.0161 0.0190 0.0043 0.0605 0.0406 -0.0139 -0.1249 0.0453 0.0064 0.0791    Highest Quarter Return 0.0770 2023-12-31    Lowest Quarter Return -0.0548 2022-09-30    Year-to-Date Return -0.0331 2026-09-30 Average Annual Returns Unlike the returns in the bar chart, the returns in the table reflect the maximum applicable sales charges. After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes. After-tax returns for Class A are shown in the table below and after-tax returns for other classes will vary. Actual after-tax returns may differ depending on your individual circumstances. The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan). Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares. Unlike the returns in the bar chart, the returns in the table reflect the maximum applicable sales charges. After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes. After-tax returns for Class A are shown in the table below and after-tax returns for other classes will vary. The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan). Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares. Return Before Taxes 0.0359 -0.0122 0.0076 Return After Taxes on Distributions 0.0207 -0.0221 -0.0019 Return After Taxes on Distributions and Sale of Fund Shares 0.0210 -0.0134 0.0017 Return Before Taxes 0.0358 -0.0121 0.0075 Return Before Taxes 0.0610 -0.0120 0.0055 Return Before Taxes 0.0824 -0.0014 0.0147 Return Before Taxes 0.0838 0.0003 0.0178 Bloomberg U.S. MBS Index 0.0858 0.0015 0.0159 Bloomberg U.S. Aggregate Bond Index 0.0730 -0.0036 0.0201 2018-10-02 Fund Summary Fund /Class: Fidelity Advisor® Limited Term Bond Fund /Fidelity® Limited Term Bond Fund Investment Objective Fidelity Advisor® Limited Term Bond Fund seeks to provide a high rate of income. Fee Table The following table describes the fees and expenses that may be incurred when you buy, hold, and sell shares of the fund. You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and examples below. Shareholder fees 0 Annual Operating Expenses 0.0020 0 0.0010 0.0030 This example helps compare the cost of investing in the fund with the cost of investing in other funds. Let's say, hypothetically, that the annual return for shares of the fund is 5% and that the fees and the annual operating expenses for shares of the fund are exactly as described in the fee table. This example illustrates the effect of fees and expenses, but is not meant to suggest actual or expected fees and expenses or returns, all of which may vary. For every $10,000 you invested, here's how much you would pay in total expenses if you sell all of your shares at the end of each time period indicated: 31 97 169 381 Portfolio Turnover The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual operating expenses or in the example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 81 % of the average value of its portfolio. 0.81 Principal Investment Strategies Normally investing at least 80% of assets in debt securities of all types and repurchase agreements for those securities. Debt securities are used by issuers to borrow money. The issuer usually pays a fixed, variable, or floating rate of interest, and must repay the amount borrowed, usually at the maturity of the security. Debt securities include corporate bonds, government securities (including Treasury securities), repurchase agreements, money market securities, mortgage and other asset-backed securities, loans and loan participations, and other securities, such as hybrids and synthetic securities, believed to have debt-like characteristics (e.g., securities classified as Tier 2 Regulatory capital, securities that rank above share capital in an insolvency waterfall, securities with maturity dates and non-cancellable interest payment structures).  A repurchase agreement is an agreement to buy a security at one price and a simultaneous agreement to sell it back at an agreed-upon price. Derivative instruments that provide investment exposure to the investments above or exposure to one or more market risk factors associated with such investments are included in the fund's 80% policy, consistent with the fund's investment policies and limitations with respect to investments in derivatives. Allocating the fund's assets across investment-grade, high yield, and emerging markets debt securities. Using the Fidelity Limited Term Composite Index℠ as a guide in allocating assets across the investment-grade and high yield asset classes. Emerging markets include countries that have an emerging stock market as defined by MSCI, countries or markets with low- to middle-income economies as classified by the World Bank, and other countries or markets that the Adviser identifies as having similar emerging markets characteristics. Investing up to 30% of assets in lower-quality debt securities (those of less than investment-grade quality, also referred to as high yield debt securities or junk bonds). Normally maintaining a dollar-weighted average maturity between two and five years. Managing the fund to have similar overall interest rate risk to the index. Investing in domestic and foreign issuers. Allocating assets across different asset classes, market sectors, and maturities. Investing in collateralized loan obligations (CLO). Analyzing the credit quality of the issuer, the issuer's potential for success, the credit, currency, and economic risks of the security and its issuer, security-specific features, current and potential future valuation, and trading opportunities to select investments. Engaging in transactions that have a leveraging effect on the fund, including investments in derivatives - such as swaps (interest rate, total return, and credit default), options, and futures contracts - and forward-settling securities, to adjust the fund's risk exposure. Interest Rate Changes. Interest rate increases can cause the price of a debt security to decrease. Foreign Exposure. Foreign markets, particularly emerging markets, can be more volatile than the U.S. market due to increased risks of adverse issuer, political, regulatory, market, or economic developments and can perform differently from the U.S. market. Foreign exchange rates also can be extremely volatile. Prepayment. The ability of an issuer of a debt security to repay principal prior to a security's maturity can cause greater price volatility if interest rates change. Issuer-Specific Changes. The value of an individual security or particular type of security can be more volatile than, and can perform differently from, the market as a whole. A decline in the credit quality of an issuer or a provider of credit support (such as guarantees) or a maturity-shortening structure (such as demand and put features) for a security can cause the price of a security to decrease. Lower-quality debt securities (those of less than investment-grade quality, also referred to as high yield debt securities or junk bonds) involve greater risk of default or price changes due to changes in the credit quality of the issuer. The value of lower-quality debt securities can be more volatile due to increased sensitivity to adverse issuer, political, regulatory, market, or economic developments. CLO tranches can experience substantial losses due to actual and anticipated defaults, as well as aversion to CLO securities as a class. Investments in covenant-lite loans carry more risk than traditional loans as they allow issuers to engage in activities that would otherwise be difficult or impossible under a traditional loan agreement. In the event of default, covenant-lite obligations have lower recovery values as the lender may not have the opportunity to negotiate with the borrower prior to default. Leverage Risk. Leverage can increase market exposure, magnify investment risks, and cause losses to be realized more quickly. An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency .   You could lose money by investing in the fund. Performance The following information is intended to help you understand the risks of investing in the fund. The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index, a hypothetical composite of market indexes, and an additional index over various periods of time. The hypothetical composite of market indexes and additional index have characteristics relevant to the fund's investment strategies. Index descriptions appear in the "Additional Index Information" section of the prospectus. Past performance (before and after taxes) is not an indication of future performance. Visit www.fidelity.com for more recent performance information. The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index, a hypothetical composite of market indexes, and an additional index over various periods of time. Past performance (before and after taxes) is not an indication of future performance. www.fidelity.com Year-by-Year Returns 0.0251 0.0188 0.0071 0.0603 0.0516 -0.0124 -0.0587 0.0626 0.0491 0.0668    Highest Quarter Return 0.0456 2020-06-30    Lowest Quarter Return -0.0365 2022-03-31    Year-to-Date Return -0.0022 2026-09-30 Average Annual Returns After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes. Actual after-tax returns may differ depending on your individual circumstances. The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan). Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares. After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes. The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan). Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares. Return Before Taxes 0.0668 0.0203 0.0263 Return After Taxes on Distributions 0.0498 0.0099 0.0167 Return After Taxes on Distributions and Sale of Fund Shares 0.0393 0.0111 0.0161 Fidelity Limited Term Composite Index℠ 0.0667 0.0203 0.0267 Bloomberg U.S. 1-5 Year Government/Credit Bond Index 0.0611 0.0156 0.0217 Bloomberg U.S. Aggregate Bond Index 0.0730 -0.0036 0.0201 Fund Summary Fund /Class: Fidelity Advisor® Limited Term Bond Fund /A, M, C, I, Z   Investment Objective Fidelity Advisor® Limited Term Bond Fund seeks to provide a high rate of income. Fee Table The following table describes the fees and expenses that may be incurred when you buy, hold, and sell shares of the fund. You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and examples below. You may qualify for sales charge discounts if you and your family invest, or agree to invest in the future, at least $ 50,000 in the fund or certain other Fidelity ® funds. More information about these and other discounts is available from your investment professional and in the "Fund Distribution" section beginning on page 36 of the prospectus and in the sales charge waiver appendix to the prospectus. You may qualify for sales charge discounts if you and your family invest, or agree to invest in the future, at least $ 50,000 in the fund or certain other Fidelity ® funds. More information about these and other discounts is available from your investment professional and in the "Fund Distribution" section beginning on page 36 of the prospectus 50000 Shareholder fees 0.0275 0.0275 0 0 0 0 0 0.0100 0 0 Purchases of $250,000 or more will not be subject to a front-end sales charge, but may be subject to a 0.50% contingent deferred sales charge (CDSC) if the intermediary firm has elected an upfront finder's fee at the time the shares are purchased, or a 0.75% CDSC if the shares purchased are recordkept in a Fidelity Advisor ® 401(k) Retirement Plan. Purchases of $250,000 or more will not be subject to a front-end sales charge but may be subject to a 0.25% CDSC if a finder's fee is paid at the time the shares are purchased. On Class C shares redeemed less than one year after purchase. Annual Operating Expenses 0.0020 0.0020 0.0020 0.0020 0.0020 0.0025 0.0025 0.0100 0 0 0.0015 0.0015 0.0017 0.0015 0.0005 0.0060 0.0060 0.0137 0.0035 0.0025 -0.0000 -0.0000 -0.0000 -0.0005 -0.0000 0.0060 0.0060 0.0137 0.0030 0.0025 2027-12-31 This example helps compare the cost of investing in the fund with the cost of investing in other funds. Let's say, hypothetically, that the annual return for shares of the fund is 5% and that the fees and the annual operating expenses for shares of the fund are exactly as described in the fee table. This example illustrates the effect of fees and expenses, but is not meant to suggest actual or expected fees and expenses or returns, all of which may vary. For every $10,000 you invested, here's how much you would pay in total expenses if you sell all of your shares at the end of each time period indicated and if you hold your shares: 335 335 335 335 239 139 31 31 26 26 462 462 462 462 434 434 106 106 80 80 601 601 601 601 750 750 190 190 141 141 1004 1004 1004 1004 1435 1435 437 437 318 318 Portfolio Turnover The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual operating expenses or in the example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 81 % of the average value of its portfolio. 0.81 Principal Investment Strategies Normally investing at least 80% of assets in debt securities of all types and repurchase agreements for those securities. Debt securities are used by issuers to borrow money. The issuer usually pays a fixed, variable, or floating rate of interest, and must repay the amount borrowed, usually at the maturity of the security. Debt securities include corporate bonds, government securities (including Treasury securities), repurchase agreements, money market securities, mortgage and other asset-backed securities, loans and loan participations, and other securities, such as hybrids and synthetic securities, believed to have debt-like characteristics (e.g., securities classified as Tier 2 Regulatory capital, securities that rank above share capital in an insolvency waterfall, securities with maturity dates and non-cancellable interest payment structures).  A repurchase agreement is an agreement to buy a security at one price and a simultaneous agreement to sell it back at an agreed-upon price. Derivative instruments that provide investment exposure to the investments above or exposure to one or more market risk factors associated with such investments are included in the fund's 80% policy, consistent with the fund's investment policies and limitations with respect to investments in derivatives. Allocating the fund's assets across investment-grade, high yield, and emerging markets debt securities. Using the Fidelity Limited Term Composite Index℠ as a guide in allocating assets across the investment-grade and high yield asset classes. Emerging markets include countries that have an emerging stock market as defined by MSCI, countries or markets with low- to middle-income economies as classified by the World Bank, and other countries or markets that the Adviser identifies as having similar emerging markets characteristics. Investing up to 30% of assets in lower-quality debt securities (those of less than investment-grade quality, also referred to as high yield debt securities or junk bonds). Normally maintaining a dollar-weighted average maturity between two and five years. Managing the fund to have similar overall interest rate risk to the index. Investing in domestic and foreign issuers. Allocating assets across different asset classes, market sectors, and maturities. Investing in collateralized loan obligations (CLO). Analyzing the credit quality of the issuer, the issuer's potential for success, the credit, currency, and economic risks of the security and its issuer, security-specific features, current and potential future valuation, and trading opportunities to select investments. Engaging in transactions that have a leveraging effect on the fund, including investments in derivatives - such as swaps (interest rate, total return, and credit default), options, and futures contracts - and forward-settling securities, to adjust the fund's risk exposure. Interest Rate Changes. Interest rate increases can cause the price of a debt security to decrease. Foreign Exposure. Foreign markets, particularly emerging markets, can be more volatile than the U.S. market due to increased risks of adverse issuer, political, regulatory, market, or economic developments and can perform differently from the U.S. market. Foreign exchange rates also can be extremely volatile. Prepayment. The ability of an issuer of a debt security to repay principal prior to a security's maturity can cause greater price volatility if interest rates change. Issuer-Specific Changes. The value of an individual security or particular type of security can be more volatile than, and can perform differently from, the market as a whole. A decline in the credit quality of an issuer or a provider of credit support (such as guarantees) or a maturity-shortening structure (such as demand and put features) for a security can cause the price of a security to decrease. Lower-quality debt securities (those of less than investment-grade quality, also referred to as high yield debt securities or junk bonds) involve greater risk of default or price changes due to changes in the credit quality of the issuer. The value of lower-quality debt securities can be more volatile due to increased sensitivity to adverse issuer, political, regulatory, market, or economic developments. CLO tranches can experience substantial losses due to actual and anticipated defaults, as well as aversion to CLO securities as a class. Investments in covenant-lite loans carry more risk than traditional loans as they allow issuers to engage in activities that would otherwise be difficult or impossible under a traditional loan agreement. In the event of default, covenant-lite obligations have lower recovery values as the lender may not have the opportunity to negotiate with the borrower prior to default. Leverage Risk. Leverage can increase market exposure, magnify investment risks, and cause losses to be realized more quickly. An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency .   You could lose money by investing in the fund. Performance The following information is intended to help you understand the risks of investing in the fund. The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index, a hypothetical composite of market indexes, and an additional index over various periods of time. The hypothetical composite of market indexes and additional index have characteristics relevant to the fund's investment strategies. Index descriptions appear in the "Additional Index Information" section of the prospectus. Past performance (before and after taxes) is not an indication of future performance. Visit institutional.fidelity.com for more recent performance information. The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index, a hypothetical composite of market indexes, and an additional index over various periods of time. Past performance (before and after taxes) is not an indication of future performance. institutional.fidelity.com Year-by-Year Returns The returns in the bar chart do not reflect any applicable sales charges; if sales charges were reflected, returns would be lower than those shown. The returns in the bar chart do not reflect any applicable sales charges; if sales charges were reflected, returns would be lower than those shown. 0.0211 0.0157 0.0040 0.0572 0.0485 -0.0154 -0.0617 0.0595 0.0460 0.0637    Highest Quarter Return 0.0450 2020-06-30    Lowest Quarter Return -0.0373 2022-03-31    Year-to-Date Return -0.0045 2026-09-30 Average Annual Returns Unlike the returns in the bar chart, the returns in the table reflect the maximum applicable sales charges. After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes. After-tax returns for Class A are shown in the table below and after-tax returns for other classes will vary. Actual after-tax returns may differ depending on your individual circumstances. The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan). Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares. Unlike the returns in the bar chart, the returns in the table reflect the maximum applicable sales charges. After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes. After-tax returns for Class A are shown in the table below and after-tax returns for other classes will vary. The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan). Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares. Return Before Taxes 0.0345 0.0116 0.0203 Return After Taxes on Distributions 0.0192 0.0024 0.0119 Return After Taxes on Distributions and Sale of Fund Shares 0.0202 0.0049 0.0119 Return Before Taxes 0.0336 0.0116 0.0203 Return Before Taxes 0.0447 0.0094 0.0168 Return Before Taxes 0.0668 0.0201 0.0259 Return Before Taxes 0.0674 0.0210 0.0309 Fidelity Limited Term Composite Index℠ 0.0667 0.0203 0.0267 Bloomberg U.S. 1-5 Year Government/Credit Bond Index 0.0611 0.0156 0.0217 Bloomberg U.S. Aggregate Bond Index 0.0730 -0.0036 0.0201 2018-10-02 Fund Summary Fund: Fidelity® Limited Term Securitized Completion Fund Investment Objective Fidelity® Limited Term Securitized Completion Fund seeks a high level of current income. Fee Table The following table describes the fees and expenses that may be incurred when you buy, hold, and sell shares of the fund. Shareholder fees 0 Annual Operating Expenses 0.0000 0 0.0000 0.0000 This example helps compare the cost of investing in the fund with the cost of investing in other funds. Let's say, hypothetically, that the annual return for shares of the fund is 5% and that the fees and the annual operating expenses for shares of the fund are exactly as described in the fee table. This example illustrates the effect of fees and expenses, but is not meant to suggest actual or expected fees and expenses or returns, all of which may vary. For every $10,000 you invested, here's how much you would pay in total expenses if you sell all of your shares at the end of each time period indicated: 0 0 0 0 Portfolio Turnover The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual operating expenses or in the example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 155 % of the average value of its portfolio. 1.55 Principal Investment Strategies Normally investing at least 80% of assets in investment-grade securitized debt securities (those of medium and high quality) and repurchase agreements for those securities. Securitized debt securities are interests in pools of mortgages, loans, receivables, or other assets, and include such instruments as mortgage-backed securities, commercial mortgage-backed securities, and other asset-backed securities that are issued by the U.S. Government, its agencies or instrumentalities, foreign governments, financial institutions, trusts and corporations. Payment of principal or interest on securitized debt instruments generally depends on the cash flows generated by the underlying assets and may be supported by letters of credit, surety bonds, or other credit enhancements. Investment grade securities in which the fund invests include securities or issuers rated at least BBB- or its equivalent by at least one nationally recognized statistical ratings organization (NRSRO), or, if unrated, determined by the Adviser to be of comparable quality. A repurchase agreement is an agreement to buy a security at one price and a simultaneous agreement to sell it back at an agreed-upon price. Derivative instruments that provide investment exposure to the investments above or exposure to one or more market risk factors associated with such investments are included in the fund's 80% policy, consistent with the fund's investment policies and limitations with respect to investments in derivatives. Investing in U.S. Government securities issued by entities that are chartered or sponsored by Congress but whose securities are neither issued nor guaranteed by the U.S. Treasury. Managing the fund to have similar overall interest rate risk to the Fidelity Limited Term Securitized Completion Fund Composite Blended Index. Investing in domestic and foreign issuers. Analyzing the credit quality of the issuer, security-specific features, current and potential future valuation, and trading opportunities to select investments. Normally maintaining a dollar-weighted average maturity between two and five years. Allocating assets across different market sectors and maturities. Investing in lower-quality debt securities (those of less than investment-grade quality, also referred to as high yield debt securities or junk bonds). Engaging in transactions that have a leveraging effect on the fund, including investments in derivatives - such as swaps (interest rate, total return, and credit default), options, and futures contracts - and forward-settling securities, to adjust the fund's risk exposure. Interest Rate Changes. Interest rate increases can cause the price of a debt security to decrease. Foreign Exposure. Foreign markets can be more volatile than the U.S. market due to increased risks of adverse issuer, political, regulatory, market, or economic developments and can perform differently from the U.S. market. Securitized Debt Securities Exposure. Securitized debt securities are dependent on the cash flows generated by the underlying assets and can be significantly affected by changes in interest rates, the availability of information concerning the underlying assets and their structure, and the creditworthiness of the originators of the loans or other receivables or the entities providing credit support. Prepayment. The ability of an issuer of a debt security to repay principal prior to a security's maturity can cause greater price volatility if interest rates change. Issuer-Specific Changes. The value of an individual security or particular type of security can be more volatile than, and can perform differently from, the market as a whole. A decline in the credit quality of an issuer or a provider of credit support (such as guarantees) or a maturity-shortening structure (such as demand and put features) for a security can cause the price of a security to decrease. Lower-quality debt securities (those of less than investment-grade quality, also referred to as high yield debt securities or junk bonds) involve greater risk of default or price changes due to changes in the credit quality of the issuer. The value of lower-quality debt securities can be more volatile due to increased sensitivity to adverse issuer, political, regulatory, market, or economic developments. U.S. Government Obligations Risk. Certain securities in which the fund may invest, including securities issued by certain U.S. Government agencies and U.S. Government sponsored enterprises, are not guaranteed by the U.S. Government or supported by the full faith and credit of the United States. Leverage Risk. Leverage can increase market exposure, magnify investment risks, and cause losses to be realized more quickly. High Portfolio Turnover. High portfolio turnover (more than 100%) may result in increased transaction costs and potentially higher capital gains or losses. The effects of higher than normal portfolio turnover may adversely affect the fund's performance. An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency .   You could lose money by investing in the fund. Performance The following information is intended to help you understand the risks of investing in the fund. The information illustrates the performance of the fund's shares over the past year and compares the performance of the fund's shares to the performance of a securities market index, a hypothetical composite of market indexes, and an additional index over various periods of time. The hypothetical composite of market indexes and additional index have characteristics relevant to the fund's investment strategies. Index descriptions appear in the "Additional Index Information" section of the prospectus. Past performance (before and after taxes) is not an indication of future performance. Visit www.fidelity.com for more recent performance information. The information illustrates the performance of the fund's shares over the past year and compares the performance of the fund's shares to the performance of a securities market index, a hypothetical composite of market indexes, and an additional index over various periods of time. Past performance (before and after taxes) is not an indication of future performance. www.fidelity.com Year-by-Year Returns 0.0642    Highest Quarter Return 0.0176 2025-03-31    Lowest Quarter Return 0.0126 2025-12-31    Year-to-Date Return 0.0084 2026-09-30 Average Annual Returns After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes. Actual after-tax returns may differ depending on your individual circumstances. The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan). Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares . After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes. The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan). Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares . Return Before Taxes 0.0642 0.0665 Return After Taxes on Distributions 0.0446 0.0466 Return After Taxes on Distributions and Sale of Fund Shares 0.0377 0.0423 Fidelity Limited Term Securitized Completion Fund Composite Blended Index 0.0624 0.0655 Bloomberg U.S. Fixed Rate Asset-Backed Securities Index 0.0593 0.0636 Bloomberg U.S. Aggregate Bond Index 0.0730 0.0670 2024-05-30 A Fidelity Management & Research Company LLC (FMR) has contractually agreed to reimburse the fund to the extent that total operating expenses (excluding interest, fees and expenses of the Independent Trustees, and acquired fund fees and expenses (including fees and expenses associated with a wholly owned subsidiary), if any, as well as non-operating expenses such as brokerage commissions and fees and expenses associated with the fund's securities lending program, if applicable), as a percentage of its average net assets, exceed 0.003% (the Expense Cap). If at any time during the current fiscal year expenses for the fund fall below the Expense Cap, FMR reserves the right to recoup through the end of the fiscal year any expenses that were reimbursed during the current fiscal year up to, but not in excess of, the Expense Cap. This arrangement will remain in effect through December 31, 2029 . FMR may not terminate this arrangement before the expiration date without the approval of the Board of Trustees and may extend it in its discretion after that date. A From August 17, 2018 . A Class A and Class M purchases of $1 million or more will not be subject to a front-end sales charge. Such Class A and Class M purchases may be subject, upon redemption, to a contingent deferred sales charge (CDSC) of 0.75% and 0.25%, respectively. B On Class C shares redeemed less than one year after purchase. A Fidelity Management & Research Company LLC (FMR) has contractually agreed to reimburse Class Z of the fund to the extent that total operating expenses (excluding interest, certain taxes, fees and expenses of the Independent Trustees, extraordinary expenses, and acquired fund fees and expenses (including fees and expenses associated with a wholly owned subsidiary), if any, as well as non-operating expenses such as brokerage commissions and fees and expenses associated with the fund's securities lending program, if applicable), as a percentage of its average net assets, exceed 0.36% (the Expense Cap). If at any time during the current fiscal year expenses for Class Z of the fund fall below the Expense Cap, FMR reserves the right to recoup through the end of the fiscal year any expenses that were reimbursed during the current fiscal year up to, but not in excess of, the Expense Cap. This arrangement will remain in effect through December 31, 2027 . FMR may not terminate this arrangement before the expiration date without the approval of the Board of Trustees and may extend it in its discretion after that date. A From October 2, 2018 . A Purchases of $250,000 or more will not be subject to a front-end sales charge, but may be subject to a 0.50% contingent deferred sales charge (CDSC) if the intermediary firm has elected an upfront finder's fee at the time the shares are purchased, or a 0.75% CDSC if the shares purchased are recordkept in a Fidelity Advisor ® 401(k) Retirement Plan. B Purchases of $250,000 or more will not be subject to a front-end sales charge but may be subject to a 0.25% CDSC if a finder's fee is paid at the time the shares are purchased. C On Class C shares redeemed less than one year after purchase. A Fidelity Management & Research Company LLC (FMR) has contractually agreed to reimburse Class I of the fund to the extent that total operating expenses (excluding interest, certain taxes, fees and expenses of the Independent Trustees, proxy and shareholder meeting expenses, extraordinary expenses, and acquired fund fees and expenses (including fees and expenses associated with a wholly owned subsidiary), if any, as well as non-operating expenses such as brokerage commissions and fees and expenses associated with the fund's securities lending program, if applicable), as a percentage of its average net assets, exceed 0.30% (the Expense Cap). If at any time during the current fiscal year expenses for Class I of the fund fall below the Expense Cap, FMR reserves the right to recoup through the end of the fiscal year any expenses that were reimbursed during the current fiscal year up to, but not in excess of, the Expense Cap. This arrangement will remain in effect through December 31, 2027 . FMR may not terminate this arrangement before the expiration date without the approval of the Board of Trustees and may extend it in its discretion after that date. A From October 2, 2018 . A From May 30, 2024 .