VGOF-SA1 10/24

LEGG MASON PARTNERS INSTITUTIONAL TRUST

LEGG MASON PARTNERS MONEY MARKET TRUST

SUPPLEMENT DATED OCTOBER 2, 2024, TO THE

STATEMENT OF ADDITIONAL INFORMATION (“SAI”)

OF EACH FUND LISTED IN SCHEDULE A

The following replaces the second paragraph and accompanying table in the section titled “DISCLOSURE OF PORTFOLIO HOLDINGS — Ongoing Arrangements” in each fund’s SAI:

Set forth below is a list, as of October 2, 2024, of those parties with whom the Manager, on behalf of the Fund, has authorized ongoing arrangements that include the release of portfolio holdings information in accordance with the policy, as well as the maximum frequency of the release under such arrangements, and the minimum length of the lag, if any, between the date of the information and the date on which the information is disclosed. The ongoing arrangements may vary for each party, and it is possible that not every party will receive information for the Fund. The parties identified below as recipients are service providers, fund rating agencies, consultants and analysts.

SCHEDULE A

Please retain this supplement for future reference.

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