Summary Prospectus by Investment Company (Form 497K)

481 P3 11/25

FRANKLIN FUND ALLOCATOR SERIES

SUPPLEMENT DATED NOVEMBER 10, 2025

TO THE SUMMARY PROSPECTUS, PROSPECTUS AND

STATEMENT OF ADDITIONAL INFORMATION

EACH DATED MAY 1, 2025, OF

FRANKLIN GLOBAL ALLOCATION FUND

The equity securities in which the Fund invests are primarily common stock. The Fund may invest in companies in any economic sector or of any market capitalization, but from time to time, based on economic conditions, the Fund may have significant investments in particular sectors. The debt securities in which the Fund may invest include all varieties of fixed, floating and variable rate instruments, including secured and unsecured bonds and senior floating rate and term loans. Bond investments may include U.S. and foreign corporate debt, U.S. Treasuries and foreign government bonds. The Fund may invest in debt securities of any duration or maturity. The Fund generally invests in investment grade debt securities, but may invest in bonds rated below investment grade, sometimes referred to as "junk bonds." The investment manager expects that the Fund may invest up to 10% (but no more than 15%) of its assets in alternative strategies. The Fund's investments in alternative strategies may include investments that provide exposure to commodities such as private funds, commodity-linked notes, commodity futures and commodity exchange traded funds (ETFs).

The equity securities in which the Fund invests include common or preferred stock, rights, warrants and other instruments whose price is linked to the value of common stock of U.S. and foreign companies. The equity securities in which the Fund invests are primarily common stock. The Fund may invest in companies in any economic sector or of any market capitalization, but from time to time, based on economic conditions, the Fund may have

significant investments in particular sectors. The debt securities in which the Fund may invest include all varieties of fixed, floating and variable rate instruments, including secured and unsecured bonds and senior floating rate and term loans. Bond investments may include U.S. and foreign corporate debt, U.S. Treasuries and foreign government bonds. The investment manager expects that the Fund may invest up to 10% (but no more than 15%) of its assets in alternative strategies. The Fund's investments in alternative strategies may include investments that provide exposure to commodities such as private funds, commodity-linked notes, commodity futures and commodity exchange traded funds (ETFs).

Tax: The tax treatment of the Fund's use of commodity-linked derivative instruments (including commodity-linked notes) may be adversely affected by changes in legislation, regulations or other legally binding authority. If, as a result of any such adverse action, the income of the Fund from certain commodity-linked derivatives was treated as non-qualifying income for purposes of the Fund's qualification as a regulated investment company, the Fund might fail to qualify as such and be subject to federal income tax at the Fund level. As a regulated investment company, the Fund must derive at least 90% of its gross income for each taxable year from sources treated as qualifying income under the Code. The Internal Revenue Service (IRS) has issued a number of private letter rulings to other mutual funds, upon which the Fund cannot rely, which indicate that income from a fund's investment in certain commodity-linked notes constitutes qualifying income. However, in September 2016 the Internal Revenue Service announced that it will no longer issue private letter rulings on questions relating to the treatment of a corporation as a regulated investment company that require a determination of whether a financial instrument or position is a security under section 2(a)(36) of the Investment Company Act of 1940 (1940 Act). A financial instrument or position that constitutes a security under section 2(a)(36) of the 1940 Act generates qualifying income for a corporation taxed as a regulated investment company. The IRS's announcement caused it to revoke the portion of any rulings relating to a mutual fund's investment in commodity-linked notes that required such a determination, some of which have been revoked prospectively as of a date agreed upon with the Internal Revenue Service.

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Accordingly, the Fund may invest in certain commodity-linked notes directly only to the extent that such commodity-linked notes constitute securities under section 2(a)(36) of the 1940 Act. It is possible that the IRS may issue further guidance, or Congress may enact legislation, that adversely affects the tax treatment of the Fund's use of commodity-linked derivative instruments (which guidance might be applied retroactively to the Fund), it could limit the Fund's ability to pursue its investment strategy and the Fund might not qualify as a regulated investment company for one or more years. In this event, the Fund's board of trustees may authorize a change in investment strategy or Fund liquidation. In lieu of potential disqualification, the Fund is permitted to pay a tax for certain failures to satisfy the income requirement, which, in general, are limited to those due to reasonable cause and not willful neglect. The Fund also may incur transaction and other costs to comply with any new or additional guidance from the IRS.

Credit-linked notes (CLNs) CLNs are typically set-up as a "pass-through" note structure created by a broker or bank as an alternative investment for funds or other purchasers to directly buying a bond or group of bonds. CLNs are typically issued at par, with a one to one relationship with the notional value to the underlying bond(s). The performance of the CLN, however, including maturity value, is linked to the performance of the specified underlying bond(s) as well as that of the issuing entity.

In addition to the risk of loss of its principal investment, the Fund bears the risk that the issuer of the CLN will default or become bankrupt. In such an event, the Fund may have difficulty being repaid, or fail to be repaid, the principal amount of its investment. A downgrade or impairment to the credit rating of the issuer will also likely impact negatively the price of the CLN, regardless of the price of the bond(s) underlying the CLNs. A CLN is typically structured as a limited recourse, unsecured obligation of the issuer of such security such that the security will usually be the obligation solely of the issuer and will not be an obligation or responsibility of any other person, including the issuer of the underlying bond(s).

Most CLNs are structured as Rule 144A securities so that they may be freely traded among institutional buyers. However, the

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market for CLNs may be, or suddenly can become, illiquid. The other parties to the transaction may be the only investors with sufficient understanding of the CLN to be interested in bidding for it. Changes in liquidity may result in significant, rapid and unpredictable changes in the prices of CLNs. In certain cases, a market price for a CLN may not be available or may not be reliable, and the Fund could experience difficulty in selling such security at a price the investment manager believes is fair.

Please retain this supplement for future reference.

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