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

Filed by theRegistrant☒Filed by a Party other than the Registrant☐

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☐ Preliminary ProxyStatement

☐ Confidential, for Use of the Commission Only (as permitted by Rule14a-6(e)(2))

☐ Definitive ProxyStatement

☒Definitive AdditionalMaterials

☐ Soliciting Material Pursuant to §240.14a-12

TREEHOUSE FOODS, 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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TREEHOUSE FOODS, INC.

IMPORTANT ANNUAL MEETING INFORMATION

 

Vote by Internet

• Go towww.envisionreports.com/thfi

• Or scan the QR code with yoursmartphone

• Follow the steps outlined on the securewebsite

Important Notice Regarding the Availability of Proxy Materials for the TreeHouse Foods, Inc. Stockholder Meeting to be Held on Thursday, April 26, 2018

Under Securities and Exchange Commission rules, you are receiving this notice that the proxy materials for the annual stockholders’ meeting are available on the Internet. Follow the instructions below to view the materials and vote online or request a copy. The items to be voted on and location of the annual meeting are on the reverse side. Your vote is important!

This communication presents only an overview of the more complete proxy materials that are available to you on the Internet. We encourage you to access and review all of the important information contained in the proxy materials before voting. The Proxy Statement, Annual Report and other proxy materials are available at:

Easy Online Access — A Convenient Way to View Proxy Materials and Vote When you go online to view materials, you can also vote your shares.

Step 1: Go to www.envisionreports.com/thfi to view the materials.

Step 2: Click on Cast Your Vote or Request Materials. Step 3: Follow the instructions on the screen to log in.

Step 4: Make your selection as instructed on each screen to select delivery preferences and vote.

When you go online, you can also help the environment by consenting to receive electronic delivery of future materials.

Obtaining a Copy of the Proxy Materials – If you want to receive a copy of these documents, you must request one. There is no charge to you for requesting a copy. Please make your request for a copy as instructed on the reverse side on or before April 13, 2018 to facilitate timely delivery.

02RLVB

Stockholder Meeting Notice

 

Dear TreeHouse Foods, Inc. Stockholder:

The 2018 Annual Meeting of Stockholders of TreeHouse Foods, Inc. (“the Company”) will be held at 2015 Spring Road, Lower Level, Conference Room A, Oak Brook, IL 60523 on Thursday, April 26, 2018 at 9:00 AM Central Daylight Time.

Proposals to be considered at the Annual Meeting:

(1) To elect four directors to hold office until the 2021 Annual Meeting ofStockholders;

(2) To ratify the selection of Deloitte & Touche LLP as our independent registered public accounting firm for fiscal year 2018; and

(3) To provide an advisory vote to approve the Company’s executivecompensation.

Management recommends a vote “FOR” Items 1, 2, and 3.

The Board of Directors has fixed the close of business on February 26, 2018 as the record date (the “Record Date”) for the determination of stockholders entitled to receive notice of and to vote at the Annual Meeting or any adjournment(s) thereof.

Stockholders of record as of the Record Date are encouraged and cordially invited to attend the Annual Meeting. Directions to attend the annual meeting where you may vote in person can be found on our website, www.treehousefoods.com.

Meeting Location:

2015 Spring Road Lower Level Conference Room A Oakbrook, IL 60523

The following materials are available for you to review online:

• the Company’s 2018 Proxy Statement (including all attachmentsthereto);

• the Company’s 10-K for the year ended December 31, 2017;and

• any amendments to the foregoing materials that are required to be furnished tostockholders.

PLEASE NOTE – YOU CANNOT VOTE BY RETURNING THIS NOTICE. To vote your shares you must vote online or request a paper copy of the proxy materials to receive a proxy card. If you wish to attend and vote at the meeting, please bring this notice with you.

Here’s how to order a copy of the proxy materials and select a future delivery preference:

Paper copies: Current and future paper delivery requests can be submitted via the telephone, Internet or email options below.

Email copies: Current and future email delivery requests must be submitted via the Internet following the instructions below. If you request an email copy of current materials, you will receive an email with a link to the materials.

PLEASE NOTE: You must use the number in the shaded bar on the reverse side when requesting a set of proxy materials.

* Internet – Go to www.envisionreports.com/thfi. Click Cast Your Vote or Request Materials. Followthe

instructions to log in and order a copy of the current meeting materials and submit your preference for email or paper delivery of future meeting materials.

* Telephone – Call us free of charge at 1-866-641-4276 and follow the instructions to log in and order a paper copy of the materials by mail for the current meeting. You can also submit a preference to receive a paper copy for future meetings.

* Email – Send email to investorvote@computershare.com with “Proxy Materials TreeHouse Foods, Inc.” in the subject line. Include in the message your full name and address, plus the number located in the shaded bar on the reverse, and state in the email that you want a paper copy of current meeting materials. You can also state your preference to receive a paper copy for futuremeetings.

To facilitate timely delivery, all requests for a paper copy of the proxy materials must be received by April 13, 2018.

02RLVB