Supplement to the

Fidelity Advisor® Limited Term Bond Fund

Class A, Class M, Class C, Class I, and Class Z

October 30, 2023

Prospectus

The following information replaces similar information found in the "Appendix" section under the "Sales Charge Waiver Policies Applied by Certain Intermediaries" heading.

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 differ from those disclosed elsewhere in a fund's prospectus. 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 Load Waivers Available at Merrill

• Shares of mutual funds available for purchase by employer-sponsored retirement, deferred compensation, and employee benefit plans (including health savings accounts) and trusts used to fund those plans provided the shares are not held in a commission-based brokerage account and shares are held for the benefit of the plan. For purposes of this provision, employer-sponsored retirement plans do not include SEP IRAs, Simple IRAs, SAR-SEPs or Keogh plans
• Shares purchased through a Merrill investment advisory program
• Brokerage class shares exchanged from advisory class shares due to the holdings moving from a Merrill investment advisory program to a Merrill brokerage account
• Shares purchased through the Merrill Edge Self-Directed platform
• Shares purchased through the systematic reinvestment of capital gains distributions and dividend reinvestment when purchasing shares of the same mutual fund in the same account
• Shares exchanged from level-load shares to front-end load shares of the same mutual fund in accordance with the description in the Merrill SLWD Supplement
• Shares purchased by eligible employees of Merrill or its affiliates and their family members who purchase shares in accounts within the employee's Merrill Household (as defined in the Merrill SLWD Supplement)
• Shares purchased by eligible persons associated with the fund as defined in this prospectus (e.g. the fund's officers or trustees)
• Shares purchased from the proceeds of a mutual fund redemption in front-end load shares provided (1) the repurchase is in a mutual fund within the same fund family; (2) the repurchase occurs within 90 calendar days from the redemption trade date, and (3) the redemption and purchase occur in the same account (known as Rights of Reinstatement). Automated transactions (i.e. systematic purchases and withdrawals) and purchases made after shares are automatically sold to pay Merrill's account maintenance fees are not eligible for Rights of Reinstatement

CDSC Waivers on Front-end, Back-end, and Level Load Shares Available at Merrill

• Shares sold due to the client's death or disability (as defined by Internal Revenue Code Section 22e(3))
• Shares sold pursuant to a systematic withdrawal program subject to Merrill's maximum systematic withdrawal limits as described in the Merrill SLWD Supplement
• Shares sold due to return of excess contributions from an IRA account
• Shares sold as part of a required minimum distribution for IRA and retirement accounts due to the investor reaching the qualified age based on applicable IRS regulation
• Front-end or level-load shares held in commission-based, non-taxable retirement brokerage accounts (e.g. traditional, Roth, rollover, SEP IRAs, Simple IRAs, SAR-SEPs or Keogh plans) that are transferred to fee-based accounts or platforms and exchanged for a lower cost share class of the same mutual fund

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

• Breakpoint discounts, as described in this prospectus, where the sales load is at or below the maximum sales load that Merrill permits to be assessed to a front-end load purchase, as described in the Merrill SLWD Supplement
• Rights of Accumulation (ROA), as described in the Merrill SLWD Supplement, which entitle clients to breakpoint discounts based on the aggregated holdings of mutual fund family assets held in accounts in their Merrill Household
• Letters of Intent (LOI), which allow for breakpoint discounts on eligible new purchases based on anticipated future eligible purchases within a fund family at Merrill, in accounts within your Merrill Household, as further described in the Merrill SLWD Supplement

Effective February 28, 2024, the following information replaces the "Principal Investment Strategies" found in the "Fund Summary" section.

• Normally investing at least 80% of assets in debt securities of all types and repurchase agreements for those securities.
• 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 20% 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.
• 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.
• Investing in Fidelity's Central funds (specialized investment vehicles used by Fidelity® funds to invest in particular security types or investment disciplines) consistent with the asset classes discussed above.

Effective February 28, 2024, the following information replaces similar information found in the "Fund Summary" section under the "Principal Investment Risks" heading.

• 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.

Effective February 28, 2024, the following information supplements information found in the "Fund Summary" section under the "Portfolio Manager(s)" heading.

Alexandre Karam (Co-Portfolio Manager) has managed the fund since 2024.

Effective February 28, 2024, the following information replaces similar information found in the "Fund Basics" section under the "Principal Investment Strategies" heading.

The Adviser normally invests at least 80% of the fund's assets in debt securities of all types and repurchase agreements for those securities. The Adviser allocates the fund's assets across investment-grade, high yield, and emerging markets debt securities. The Adviser may invest up to 20% of the fund's assets in lower-quality debt securities (those of less than investment-grade quality, also referred to as high yield debt securities or junk bonds). 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. Emerging markets tend to have relatively low gross national product per capita compared to the world's major economies and may have the potential for rapid economic growth.

The Adviser uses the Fidelity Limited Term Composite Index℠ as a guide in structuring the fund and selecting its investments. The Adviser uses the index as a guide in allocating the fund's assets across the investment-grade and high yield asset classes. The Adviser manages the fund to have similar overall interest rate risk to the index.

The Adviser considers other factors when selecting the fund's investments, including the credit quality of the issuer, security-specific features, current valuation relative to alternatives in the market, short-term trading opportunities resulting from market inefficiencies, and potential future valuation. In managing the fund's exposure to various risks, including interest rate risk, the Adviser considers, among other things, the market's overall risk characteristics, the market's current pricing of those risks, and internal views of potential future market conditions.

In addition, the fund normally maintains a dollar-weighted average maturity between two and five years. As of August 31, 2023, the fund's dollar-weighted average maturity was approximately 2.5 years and the index's dollar-weighted average maturity was approximately 2.8 years. In determining a security's maturity for purposes of calculating the fund's average maturity, an estimate of the average time for its principal to be paid may be used. This can be substantially shorter than its stated maturity.

The Adviser may invest the fund's assets in securities of foreign issuers in addition to securities of domestic issuers.

The Adviser may engage in transactions that have a leveraging effect on the fund, including investments in derivatives, regardless of whether the fund may own the asset, instrument, currency, or components of the index underlying the derivative, and forward-settling securities. The Adviser may invest a significant portion of the fund's assets in these types of investments. If the fund invests a significant portion of its assets in derivatives, its investment exposure could far exceed the value of its portfolio securities and its investment performance could be primarily dependent upon securities it does not own. The fund's derivative investments may include interest rate swaps, total return swaps, credit default swaps, options (including options on futures and swaps), forwards, and futures contracts (both long and short positions) on securities, other instruments, indexes, or currencies. Depending on the Adviser's outlook and market conditions, the Adviser may engage in these transactions to increase or decrease the fund's exposure to changing security prices, interest rates, credit qualities, foreign exchange rates, or other factors that affect security values, or to gain or reduce exposure to an asset, instrument, currency, or index.

The Adviser allocates the fund's assets among different asset classes using the composition of the index as a guide, and among different market sectors (for example, corporate, asset-backed, or government securities) and different maturities based on its view of the relative value of each sector or maturity.

In selecting foreign securities, the Adviser's analysis also considers the credit, currency, and economic risks associated with the security and the country of its issuer. The Adviser may also consider an issuer's potential for success in light of its current financial condition, its industry position, and economic and market conditions.

To earn additional income for the fund, the Adviser may use a trading strategy that involves selling (or buying) mortgage securities and simultaneously agreeing to purchase (or sell) mortgage securities on a later date at a set price. This trading strategy may increase interest rate exposure and result in an increased portfolio turnover rate which increases transaction costs and may increase taxable gains.

The Adviser uses Central funds to help invest the fund's assets. Central funds are specialized investment vehicles designed to be used by Fidelity®funds. Fidelity uses them to invest in particular security types or investment disciplines; for example, rather than buy bonds directly, the fund may invest in a Central fund that buys bonds. Fidelity generally does not charge any additional management fees for Central funds.

If the Adviser's strategies do not work as intended, the fund may not achieve its objective.

Shareholders should be aware that investments made by the fund and results achieved by the fund at any given time are not expected to be the same as those made by other funds for which the Adviser or an affiliate acts as manager, including funds with names, investment objectives, and policies that are similar to the fund.

Effective February 28, 2024, the following information replaces similar information found in the "Fund Basics" section under the "Principal Investment Risks" heading.

Foreign Exposure. Foreign securities, foreign currencies, and securities issued by U.S. entities with substantial foreign operations can involve additional risks relating to political, economic, or regulatory conditions in foreign countries. These risks include fluctuations in foreign exchange rates; withholding or other taxes; trading, settlement, custodial, and other operational risks; and the less stringent investor protection and disclosure standards of some foreign markets. All of these factors can make foreign investments, especially those in emerging markets, more volatile and potentially less liquid than U.S. investments. In addition, foreign markets can perform differently from the U.S. market.

Investing in emerging markets can involve risks in addition to and greater than those generally associated with investing in more developed foreign markets. The extent of economic development; political stability; market depth, infrastructure, and capitalization; and regulatory oversight can be less than in more developed markets. Emerging markets typically have less established legal, accounting and financial reporting systems than those in more developed markets, which may reduce the scope or quality of financial information available to investors. Emerging markets economies can be subject to greater social, economic, regulatory, and political uncertainties and can be extremely volatile. All of these factors can make emerging markets securities more volatile and potentially less liquid than securities issued in more developed markets.

Global economies and financial markets are becoming increasingly interconnected, which increases the possibilities that conditions in one country or region might adversely impact issuers or providers in, or foreign exchange rates with, a different country or region.

Effective February 28, 2024, the following information supplements the biographical information found in the "Fund Management" section under the "Portfolio Manager(s)" heading.

Alexandre Karam is Co-Portfolio Manager of Fidelity Advisor® Limited Term Bond Fund, which he has managed since 2024. He also manages other funds. Since joining Fidelity Investments in 2016, Mr. Karam has worked as a research analyst and portfolio manager.

Effective February 28, 2024, the following information replaces similar information found in the "Additional Index Information" section under the "Appendix" heading.

Fidelity Limited Term Composite IndexSM is a customized blend of unmanaged indexes, weighted as follows: Bloomberg U.S. 1-5 Year Credit Bond Index - 70%; Bloomberg U.S. 1-5 Year Government Bond Index - 20%; and ICE® BofA® 1-5 Year BB-B US Cash Pay High Yield Constrained Index - 10%. The composition differed in periods prior to February 28, 2024.

LTB-PSTK-0424-144 1.756204.144 April 1, 2024