tti-defa14a_20220411.htm

☐	Preliminary proxy statement.

☐	Confidential, for use of the Commission only (as permitted by Rule 14a-6(e)(2)).

☐	Definitive proxy statement.

☒	Definitive additional materials.

☐	Soliciting material under Rule 14a-12.

☒	No Fee required.

☐	Fee paid previously with preliminary materials.

☐	Check Fee computed on table in exhibit required by Item 25(b) per Exchange Act Rules 14a-6(i)(1) and 0-11.

MMMMMMMMMMMM + C 1234567890 000004 MMMMMMM ENDORSEMENT_LINE______________ SACKPACK_____________ MMMMMMMMM MR A SAMPLE Online DESIGNATION (IF ANY) ADD 1 Go to www.envisionreports.com/TTI ADD 2 or scan the QR code — login details are located ADD 3 in the shaded bar below. ADD 4 ADD 5 ADD 6 Votes submitted electronically must be received by 11:59 p.m., Eastern Time, on May 23, 2022. StockholderMeetingNotice123456789012345 Important Notice Regarding the Availability of Proxy Materials for the TETRA Technologies, Inc. Stockholder Meeting to be Held on Tuesday, May 24, 2022 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 2022 proxy statement and annual report to stockholders are available at: www.envisionreports.com/TTI Easy Online Access — View your proxy materials and vote. Step 1: Go to www.envisionreports.com/TTI. 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 selections as instructed on each screen for your delivery preferences. Step 5: Vote your shares. 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 the proxy materials, you must request one. There is no charge to you for requesting a copy. Please make your request as instructed on the reverse side on or before May 12, 2022 to facilitate timely delivery. 2NOT COY + 03LP1B

Stockholder Meeting Notice TETRA Technologies, Inc.’s Annual Meeting of Stockholders will be held on Tuesday, May 24, 2022, at the TETRA Technologies Corporate Headquarters Building, 24955 Interstate 45 North, The Woodlands, Texas, at 11:00 a.m. Local Time. Proposals to be voted on at the meeting are listed below along with the Board of Directors’ recommendations. The Board of Directors recommends a vote FOR all the nominees listed in Proposal 1, FOR Proposals 2 and 3, and makes no recommendation on Proposal 4. 1. To elect seven directors to serve one-year terms ending at the 2023 Annual Meeting of Stockholders, or until their successors have been duly elected or appointed. Nominees: 01) Mark E. Baldwin 02) Thomas R. Bates, Jr. 03) John F. Glick 04) Gina A. Luna 05) Brady M. Murphy 06) Sharon B. McGee 07) Shawn D. Williams 2. To ratify and approve the appointment of Grant Thornton LLP as TETRA’s independent registered public accounting firm for the fiscal year ending December 31, 2022. 3. To approve, on an advisory basis, the compensation of the named executive officers of TETRA Technologies, Inc 4. To vote on a stockholder proposal entitled, “Proposal 4 – Simple Majority Vote,” if properly presented at the meeting. 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. You may obtain directions to the location of the 2022 annual meeting by contacting our Investor Relations Department at 281-367-1983 or at the Investor Relations area of our website at www.tetratec.com. Here’s how to order a copy of the proxy materials and select delivery preferences: Current and future delivery requests can be submitted using the options below. If you request an email copy, you will receive an email with a link to the current meeting materials. PLEASE NOTE: You must use the number in the shaded bar on the reverse side when requesting a copy of the proxy materials. — Internet – Go to www.envisionreports.com/TTI. Click Cast Your Vote or Request Materials. — Phone – Call us free of charge at 1-866-641-4276. — Email – Send an email to investorvote@computershare.com with “Proxy Materials TETRA Technologies, Inc.” in the subject line. Include your full name and address, plus the number located in the shaded bar on the reverse side, and state that you want a paper copy of the meeting materials. To facilitate timely delivery, all requests for a paper copy of proxy materials must be received by May 12, 2022.