Benefits Handbook

This section, together with the Investment Return Fact Sheet and the Administrative Information section, also constitute part of a prospectus covering securities that have been registered under the Securities Act of 1933, as amended. See below for more details.

The Plan was most recently approved by the Internal Revenue Service as tax qualified under Sections 401(a) and 4975(e)(7) of the Internal Revenue Code by means of a favorable determination letter dated November 13, 2013. Accordingly, Marsh & McLennan Agency contributions will be deductible by Marsh & McLennan Agency within the limits set forth in the Internal Revenue Code. This section describes the Plan provisions as of January 1, 2024 which apply if you are employed on or after January 1, 2024. Former employees may be subject to other rules under prior provisions.

The date of this prospectus is March 27, 2023.

Participants may receive, without charge, upon request to the Plan Administrator, any of the documents that constitute part of the prospectus, as well as a copy of the annual report from Marsh & McLennan Companies, Inc., copies of other reports, proxy statements and other communications distributed to Marsh & McLennan Companies shareholders, and the annual report for the Plan. Copies of the documents described may be obtained from the Plan Administrator at the following address:

Marsh & McLennan Companies' annual report can be viewed at www.mmc.com/annualreport.html.

All reports and other documents subsequently filed by Marsh & McLennan Companies or the Plan pursuant to Section 13(a), 13(c), 14, 15(d) of the Securities Exchange Act of 1934, as amended, prior to the filing of a post-effective amendment which indicates that all securities offered have been sold or which deregisters all securities then remaining unsold, also will be deemed to be incorporated into this Summary Plan Description and Prospectus from the date of the filing of such reports and documents.