UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 14A

Proxy Statement Pursuant to Section 14(a) of the

Securities Exchange Act of 1934

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☐ Definitive Proxy Statement

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Marsh & McLennan Companies, Inc.

(Name of Registrant as Specified in its Charter)

(Name of Person(s) Filing Proxy Statement, if Other Than the Registrant)

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*** Exercise Your Right to Vote ***

Important Notice Regarding the Availability of Proxy Materials for the

Stockholder Meeting to Be Held on May 17, 2018.

	MARSH & McLENNAN COMPANIES, INC.
	MARSH & McLENNAN COMPANIES, INC. 1166 AVENUE OF THE AMERICAS NEW YORK, NY 10036

Meeting Information

Meeting Type:         Annual Meeting

For holders as of:    March 19, 2018

Date:    May 17, 2018          Time:    10:00 A.M. EDT

Location:    Marsh & McLennan Companies, Inc.

    1166 Avenue of the Americas

    New York, NY 10036

You are receiving this communication because you hold shares in the company named above.

This is not a ballot. You cannot use this notice to vote these shares. This communication presents only an overview of the more complete proxy materials that are available to you on the Internet. You may view the proxy materials online at www.proxyvote.com or easily request a paper copy (see reverse side).

We encourage you to access and review all of the important information contained in the proxy materials before voting.

  See the reverse side of this notice to obtain proxy

  materials and voting instructions.

—  Before You Vote  —

How to Access the Proxy Materials

	Proxy Materials Available to VIEW or RECEIVE:
	NOTICE AND PROXY STATEMENT                    ANNUAL REPORT
	How to View Online:
	Have the information that is printed in the box marked by the arrow (located on the following page) and visit: www.proxyvote.com.
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	—  How To Vote  — Please Choose One of the Following Voting Methods
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	Vote In Person: Many stockholder meetings have attendance requirements including, but not limited to, the possession of an attendance ticket issued by the entity holding the meeting. Please check the meeting materials for any special requirements for meeting attendance. At the meeting, you will need to request a ballot to vote these shares.

	Voting Items
	The Board of Directors recommends you vote FOR the following directors:
	Item 1	Election of Directors		The Board of Directors recommends you vote FOR the following proposals: Item 2    Advisory (Nonbinding) Vote to Approve Named               Executive Officer Compensation Item 3    Ratification of Selection of Independent  Registered               Public Accounting Firm Item 4    Approval of Additional Shares for Two Stock               Purchase Plans
		1a.	Anthony K. Anderson
		1b.	Oscar Fanjul
		1c.	Daniel S. Glaser
		1d.	H. Edward Hanway
		1e.	Deborah C. Hopkins
		1f.	Elaine La Roche
		1g.	Steven A. Mills
		1h.	Bruce P. Nolop
		1i.	Marc D. Oken
		1j.	Morton O. Schapiro
		1k.	Lloyd M. Yates
		1l.	R. David Yost