sbsi-20260325

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 14A

(Rule 14a-101)

INFORMATION REQUIRED IN PROXY STATEMENT

SCHEDULE 14A INFORMATION

Proxy Statement Pursuant to Section 14(a) of

the Securities Exchange Act of 1934


Filed by the Registrant			x


Filed by a Party other than the Registrant			¨

Check the appropriate box:


o			Preliminary Proxy Statement
o			Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2))
x			Definitive Proxy Statement
o			Definitive Additional Materials
o			Soliciting Material Pursuant to Sec.240.14a-12


SOUTHSIDE BANCSHARES, INC.
(Name of Registrant as Specified In Its Charter)
N/A
(Name of Person(s) Filing Proxy Statement, if other than the Registrant)

Payment of Filing Fee (Check all boxes that apply):


x			No fee required.
¨			Fee paid previously with preliminary materials.
¨			Fee computed on table in exhibit required by Item 25(b) per Exchange Act Rules 14a-6(i)(1) and 0-11.

TABLE OF CONTENTS


NOTICE OF ANNUAL MEETING OF SHAREHOLDERS		i
PROXY STATEMENT FOR THE ANNUAL MEETING OF SHAREHOLDERS		1
VOTING OF PROXY		1
REVOCABILITY OF PROXY		2
PERSONS MAKING THE SOLICITATION		2
RECORD DATE AND OUTSTANDING SHARES		2
QUORUM, VOTING RIGHTS AND PROCEDURES		2
EFFECT OF WITHHOLD VOTES, ABSTENTIONS AND BROKER NON-VOTES		3
PROPOSAL 1 – ELECTION OF DIRECTORS		3
INFORMATION ABOUT OUR DIRECTORS, NOMINEES AND EXECUTIVE OFFICERS		4
CORPORATE RESPONSIBILITY		10
CORPORATE GOVERNANCE		12
BOARD COMMITTEES		14
DIRECTOR COMPENSATION		18
	2025 Director Compensation Table	19
DIRECTOR STOCK OWNERSHIP POLICY		20
SECURITY OWNERSHIP OF CERTAIN BENEFICIAL OWNERS		21
COMPENSATION COMMITTEE REPORT		23
COMPENSATION DISCUSSION AND ANALYSIS		23
EXECUTIVE COMPENSATION		30
	Summary Compensation Table	30
	2025 All Other Compensation Table	31
	2025 Grants of Plan-Based Awards	33
	Outstanding Equity Awards at 2025 Fiscal Year End	34
	2025 Option Exercises and Stock Vested	35
	2025 Pension Benefits	36
	Potential Payments Upon Termination or Change in Control	38
	Equity Compensation Plan Information	42
PAY VERSUS PERFORMANCE		43
	Pay Versus Performance Table	43
	Compensation Actually Paid Table	44
PROPOSAL 2 – NON-BINDING ADVISORY VOTE ON EXECUTIVE COMPENSATION		47
PROPOSAL 3 – AMENDMENT TO THE RESTATED CERTIFICATE OF FORMATION TO CREATE FLEXIBLE PREFERRED STOCK		48
COMPENSATION COMMITTEE INTERLOCKS AND INSIDER PARTICIPATION		50
TRANSACTIONS WITH DIRECTORS, OFFICERS AND ASSOCIATES		50
DELINQUENT SECTION 16(a) REPORTS		50
AUDIT COMMITTEE REPORT		51
INDEPENDENT REGISTERED CERTIFIED PUBLIC ACCOUNTING FIRM		52
PROPOSAL 4 – RATIFICATION OF APPOINTMENT OF INDEPENDENT REGISTERED CERTIFIED PUBLIC ACCOUNTING FIRM		52
ANNUAL REPORT TO SHAREHOLDERS		53
SHAREHOLDER PROPOSALS		53
HOUSEHOLDING		53
GENERAL		53
APPENDIX
PROXY CARD

SOUTHSIDE BANCSHARES, INC.

1201 South Beckham Avenue

Tyler, Texas 75701

NOTICE OF ANNUAL MEETING OF SHAREHOLDERS

TO BE HELD THURSDAY, MAY 14, 2026

Dear Shareholder:

You are cordially invited to attend the 2026 Annual Meeting of Shareholders (the “Annual Meeting”) of Southside Bancshares, Inc. (the “Company”) to be held at Willow Brook Country Club, 3205 West Erwin Street, Tyler, Texas 75702, on Thursday, May 14, 2026, at 11:30 a.m., central time, for the purpose of considering and acting upon the following:

1.the election of six nominees named in this proxy statement to serve as members of the Board of Directors of the Company (the "Board”), four of whom are to serve until the 2029 Annual Meeting of Shareholders, one to serve until the 2028 Annual Meeting of Shareholders and one to serve until the 2027 Annual Meeting of Shareholders;

2.a non-binding advisory vote on the compensation of the Company's named executive officers;

3.the approval of an amendment to the Company's Restated Certificate of Formation to authorize the issuance of up to 8,000,000 shares of flexible preferred stock;

4.the ratification of the appointment by our Audit Committee of Ernst & Young LLP (“EY”) to serve as the independent registered certified public accounting firm for the Company for the year ending December 31, 2026; and

5.the transaction of such other business that may properly come before the Annual Meeting or any adjournment thereof.

Management will also report on operations and other matters affecting the Company. You will be able to ask the Company’s officers and directors questions at the Annual Meeting. Representatives from EY, the Company’s independent registered certified public accounting firm, are expected to be in attendance and available to answer your appropriate questions or make a statement if they so desire.

Only shareholders registered on the Company’s books as owners of shares of common stock at the close of business on March 16, 2026, are entitled to vote at the Annual Meeting, which we refer to as the record date.

Your attendance and vote are important. Please sign, date and return the enclosed proxy immediately in the envelope provided or you may vote your shares by telephone or Internet. It is important that you sign and return the proxy or vote by telephone or Internet, even if you plan to attend the Annual Meeting. Your proxy may be revoked by notice in writing to the Corporate Secretary at the Company’s principal executive office, located at 1201 South Beckham Avenue, Tyler, Texas 75701, at any time prior to the Annual Meeting, or by advising the Corporate Secretary at the Annual Meeting that you wish to revoke your proxy and vote your shares in person.


			By Order of the Board of Directors,


			/s/ H. J. Shands, III
			H. J. Shands, III
			Chairman of the Board

Tyler, Texas

March 25, 2026

Important Notice Regarding the Availability of Proxy Materials

for the Annual Meeting of Shareholders to be held on Thursday, May 14, 2026:

The Company's Proxy Statement and 2025 Annual Report on Form 10-K are available on the Company's website at https://southside.com/proxy.

WHETHER OR NOT YOU PLAN TO ATTEND THE MEETING, IT IS REQUESTED THAT YOU PROPERLY EXECUTE AND PROMPTLY RETURN THE ENCLOSED FORM OF PROXY IN THE ENCLOSED ADDRESSED ENVELOPE OR VOTE YOUR SHARES BY TELEPHONE OR INTERNET.

SOUTHSIDE BANCSHARES, INC.

1201 South Beckham Avenue

Tyler, Texas 75701

PROXY STATEMENT

FOR THE

ANNUAL MEETING OF SHAREHOLDERS

TO BE HELD ON THURSDAY, MAY 14, 2026

TO OUR SHAREHOLDERS:

This proxy statement is being furnished to holders of the common stock of Southside Bancshares, Inc. (the “Company”) in connection with the Company’s 2026 Annual Meeting of Shareholders (the “Annual Meeting”) to be held at Willow Brook Country Club, 3205 West Erwin Street, Tyler, Texas 75702, on Thursday, May 14, 2026, at 11:30 a.m., central time, for the purpose of considering and acting upon the following:

2.a non-binding advisory vote on the compensation of the Company's named executive officers;

3.the approval of an amendment to the Company's Restated Certificate of Formation to authorize the issuance of up to 8,000,000 shares of flexible preferred stock;

5.the transaction of such other business that may properly come before the Annual Meeting or any adjournment thereof.

This Proxy Statement and a proxy card, as well as the Company's Annual Report on Form 10-K for the year ended December 31, 2025, including financial statements, are first being sent or made available to shareholders on or about March 25, 2026.

You are encouraged to review all of the information contained in the proxy materials before voting.

VOTING OF PROXY

If your proxy is executed and returned, it will be voted as you direct. If no direction is provided, the proxy will be voted in accordance with the Board’s recommendations, as follows:

•FOR the election of all of the nominees named in this proxy statement as directors;

•FOR the approval of the advisory vote on the compensation of the Company's named executive officers;

•FOR the approval of the amendment to the Restated Certificate of Formation to create flexible preferred stock;

•FOR the ratification of the appointment of EY.

The Proxies will use their discretion with respect to voting on any other matters presented for a vote at the meeting. Additionally, if your proxy is executed and returned, it will be voted to approve the minutes of the 2025 Annual Meeting of Shareholders. This vote will not amount to a ratification of any action taken at that meeting nor will it indicate approval or disapproval of that action.

If your shares are registered in your name as the shareholder of record, you may vote by mail, telephone or Internet by following the instructions below. Voting instructions also appear on your proxy card. If you grant a proxy by telephone or by Internet, please have your proxy card available.

•To vote by mail, complete, sign, and return the enclosed proxy card in the postage paid envelope provided or return to: Vote Processing, c/o Broadridge, 51 Mercedes Way, Edgewood, New York, 11717.

•To vote by telephone, call toll free 1-800-690-6903 within the United States (“U.S.”), U.S. territories and Canada on a touch tone telephone by 11:59 p.m. eastern time on May 13, 2026. Have your proxy card in hand and follow the instructions.

•To vote by Internet, access the voting site at www.proxyvote.com. You will need the control number printed on your notice or proxy card.

The telephone and Internet voting procedures are designed to authenticate the shareholder's identity and to allow shareholders to vote their shares and confirm that their voting instructions have been properly recorded. Shareholders who vote by telephone or Internet do not need to return the proxy card.

If you hold your shares in “street name” in a stock brokerage account or through a bank, trust or other nominee, the broker or other nominee is considered the record holder and you are the beneficial owner of the shares. Beneficial owners vote their street name shares by instructing their broker or other nominee how to vote using the voting instruction form provided by the broker or

Southside Bancshares, Inc. | 2026 Proxy Statement | 1

nominee. Brokers only have authority to vote in their discretion on “routine” matters if they do not receive voting instructions from the beneficial owner of the shares.

Please note that the proposal to elect directors, the advisory vote on the compensation of the Company's named executive officers (the “Say-on-Pay” vote) and the approval of the amendment to the Company's Restated Certificate of Formation to create flexible preferred stock are not considered routine matters. Consequently, if you do not give your broker or nominee specific voting instructions with respect to such proposals, your street name shares will be treated as broker non-votes with respect to those proposals (see “Quorum, Voting Rights and Procedures” below) and will have no effect on the outcome of such proposals. The proposal to ratify the Audit Committee’s appointment of EY as the Company’s independent registered public accounting firm for the year ending December 31, 2026 is considered a routine matter.

If you hold your shares in street name and want to vote at the Annual Meeting, you must obtain from your broker or nominee a legal proxy issued in your name giving you the right to vote the shares directly at the meeting. You will not be entitled to vote at the meeting unless you present such a proxy to the Company at that time.

REVOCABILITY OF PROXY

Your proxy may be revoked by providing notice in writing to the Corporate Secretary at the Company’s principal executive offices, located at 1201 South Beckham Avenue, Tyler, Texas 75701, at any time prior to the Annual Meeting, or by advising the Corporate Secretary at the Annual Meeting that you wish to revoke your proxy and vote your shares in person. Your attendance at the Annual Meeting will not constitute automatic revocation of the proxy.

PERSONS MAKING THE SOLICITATION

The Company’s Board is soliciting the proxy. The expense of soliciting your proxy will be borne entirely by the Company and no other person or persons will bear such costs either directly or indirectly. Proxies will be solicited principally by mail, but may also be solicited by personal interview, telephone and email by directors, officers and employees of the Company who will receive no additional compensation.

RECORD DATE AND OUTSTANDING SHARES

The Company’s Board has fixed the close of business on March 16, 2026, as the record date for determining the holders of common stock of the Company entitled to notice of and to vote at the Annual Meeting. At the close of business on March 16, 2026, the record date, there were approximately 29,743,585 shares of common stock outstanding and eligible to be voted on each matter.

QUORUM, VOTING RIGHTS AND PROCEDURES

The approval of all of the proposals brought before the Annual Meeting requires that a quorum be present at the Annual Meeting. The presence, in person or by properly submitted proxy, of the holders of a majority of the shares of common stock entitled to vote at the Annual Meeting is necessary to constitute a quorum. Consequently, at least 14,871,793 shares of our common stock must be present in person or by proxy, in order for us to have a quorum at the Annual Meeting. In the event that a quorum is not represented in person or by proxy at the Annual Meeting, a majority of shares present or represented at the meeting and entitled to vote at the meeting may adjourn the Annual Meeting to a later date to allow the solicitation of additional proxies or other measures to obtain a quorum. Each shareholder is entitled to one vote on each proposal per share of common stock held as of the record date.

Proposal 1, the election of four directors to serve until the 2029 Annual Meeting, one to serve until the 2028 Annual Meeting and one to serve until the 2027 Annual Meeting, requires the affirmative vote of a majority of the votes cast by the holders of shares of common stock entitled to vote in the election of directors; provided, however, that if, as of the record date, the number of nominees for director exceeds the number of positions on the Board to be filled by election at such meeting, or a “contested election,” then the directors shall be elected by a plurality of the votes cast. A “majority of the votes cast” means that the number of shares cast “for” a director’s election exceeds the number of shares cast “against” a director’s election, with abstentions and broker non-votes counting as votes neither “for” nor “against” such director’s election. A “plurality of the votes cast” means that the director nominees who receive the highest number of “for” votes will be elected to the Board. The Board has proposed six nominees for election at the Annual Meeting. No other nominees for election to the Board have been submitted for election in accordance with our bylaws. Thus, the Board has determined that this is not a contested election, and each director nominee will be elected by a majority of the votes cast.

Under our bylaws, any incumbent director who is a nominee in an uncontested election who does not receive a majority of the votes cast shall promptly tender his or her resignation to the Board, the effectiveness of which will be conditioned upon and subject to acceptance by the Board. The Corporate Governance and Nominating Committee will make a recommendation to the Board as to whether to accept or reject the tendered resignation or whether other action should be taken, after which the Board will vote to decide whether to accept the recommendation of the Corporate Governance and Nominating Committee and will promptly disclose that decision and the rationale behind its decision.

Proposal 2, the non-binding Say-on-Pay vote, and Proposal 4, the ratification of EY as the Company’s independent registered certified public accounting firm, and any other matter that may properly come before the Annual Meeting, require approval by a majority of the shares of common stock entitled to vote on, and voted for or against, or expressly abstained from voting, with respect to the matter.

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Proposal 3, the approval of the amendment to the Company's Restated Certificate of Formation to create flexible preferred stock, requires the approval by two-thirds of the Company's outstanding shares of common stock entitled to vote in person or by proxy.

EFFECT OF WITHHOLD VOTES, ABSTENTIONS AND BROKER NON-VOTES

Shares represented at the Annual Meeting that are withheld or abstain from voting and broker non-votes votes (i.e., the submission of a proxy by a broker or nominee specifically indicating the lack of discretionary authority to vote on the matter) will be considered present for the purpose of determining a quorum at the Annual Meeting.

For Proposal 1, abstentions and broker non-votes will not be counted in determining whether a director has received a majority of the votes cast for his or her election.

For Proposals 2 and 4, and for any other matter that may properly come before the meeting, abstentions will be included in vote totals and, as such, will have the same effect on those proposals as a vote against such proposals. Broker non-votes will not be included in vote totals and, as such, will have no effect on such proposals.

For Proposal 3, abstentions and broker non-votes will have the same effect as a vote against the proposal.

PROPOSAL 1 - ELECTION OF DIRECTORS

The Board is currently comprised of 14 directors. The Board is classified into three classes, one of which is currently comprised of seven directors, one class comprised of four directors, and one class comprised of three directors. As previously disclosed, Michael J. Bosworth will retire from the Board, effective as of the Annual Meeting. If the proposed nominees are elected, following the Annual Meeting, the Board will be comprised of 13 directors, with two classes comprised of four directors and one class comprised of five directors. Under NYSE listing rules, a majority of the Board must be comprised of independent directors and board classes must be approximately equal in size. The Board has determined each director is independent under NYSE listing rules, except for Keith M. Donahoe and Lee R. Gibson. If the proposed nominees are elected at the 2026 Annual Meeting, the Board will be comprised of 85% independent directors.

The four nominees for election at the Annual Meeting to serve a three-year term expiring at the 2029 Annual Meeting, one nominee for a two-year term expiring at the 2028 Annual Meeting and one nominee for a one-year term expiring at the 2027 Annual Meeting are identified below.

Term Expiring 2029

•Lawrence L. Anderson, M.D.

•Keith M. Donahoe

•H. J. Shands, III

•Preston L. Smith

Term Expiring 2028

•Jeb W. Jones

Term Expiring 2027

•Raymond C. McKinney, CPA

All of the nominees are currently directors of the Company, and the Company's subsidiary, Southside Bank (the “Bank”), and were previously elected to the Board by the Company's shareholders, with the exception of Mr. Donahoe, Mr. Jones and Mr. McKinney, who were appointed to the Board effective November 15, 2025. For biographical information on the nominees, please see “Information About Our Directors, Nominees and Executive Officers.”

Unless otherwise instructed, proxies received in response to this solicitation will be voted in favor of the election of the persons recommended by the Corporate Governance and Nominating Committee and nominated by the Board as nominees for directors of the Company. While it is not expected that any of the nominees will be unable to qualify or accept office, if for any reason one or more of the nominees shall be unable to do so, the proxies will be voted for the substitute nominee(s) selected by the Board.

The Board recommends a vote FOR the election of each of the director nominees.

Southside Bancshares, Inc. | 2026 Proxy Statement | 3

INFORMATION ABOUT OUR DIRECTORS, NOMINEES AND EXECUTIVE OFFICERS

The following table sets forth information regarding our current directors and director nominees and their knowledge, skills and experience attributes.

Directors and Nominees

Age

Director Since

Gender

Ethnicity

Knowledge, Skills and Experience

Executive Experience

Banking/Financial Services Industry

CRE(1)

Accounting/Audit

Risk

Strategic Planning

Corporate Governance

Legal(2)

IT(3)

HR(4)

Lawrence L. Anderson, M.D.

2010

Male

White

S. Elaine Anderson, CPA

2014

Female

White

Michael J. Bosworth(5)

2017

Male

White

Kirk A. Calhoun, M.D.

2024

Male

African American

Patricia A. Callan

2014

Female

White

Shannon Dacus

2020

Female

Hispanic

Keith M. Donahoe

2025

Male

White

Alton L. Frailey

2022

Male

African American

John R. (Bob) Garrett

2009

Male

White

Lee R. Gibson, CPA

2015

Male

White

Jeb W. Jones

2025

Male

White

Raymond C. McKinney, CPA

2025

Male

White

H. J. Shands, III

2017

Male

White

Preston L. Smith

2009

Male

White

(1) Commercial Real Estate (“CRE”), including construction.

(2) Includes regulatory and compliance.

(3) Information Technology (“IT”), which includes information security.

(4) Human Resources (“HR”), which includes executive compensation.

(5) Retiring from the Board effective as of the Annual Meeting.

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The following table sets forth information regarding our director nominees, our continuing directors and our current executive officers. Our Board is divided among three classes, as described above.


NOMINEES FOR DIRECTOR TERMS TO EXPIRE AT THE 2029 ANNUAL MEETING
LAWRENCE L. ANDERSON, M.D. (69) – Dr. Anderson was the founder of Dermatology Associates of Tyler and served as the medical director from 1996 to 2012. He then served as Chief Medical Officer for Oliver Street Dermatology from 2012 to 2016 and in the same role for U.S. Dermatology Partners until 2019. He is a graduate of Washington State University and Uniformed Services University of Health Sciences in Bethesda, Maryland. He is a published author with a number of publications, presentations and lectures to his credit. Dr. Anderson’s management, leadership skills and healthcare industry knowledge, combined with his knowledge of business and finance, qualify him to be a member of the Board.
KEITH M. DONAHOE (55) – Mr. Donahoe currently serves as President and Chief Executive Officer (“CEO”) of the Company and the Bank, he has served as President of the Company and the Bank since May 2024 and CEO since January 2026. Upon joining the Bank in 2021, he first served as Austin Market President and later as Central Texas Regional President. Prior to joining Southside, he was with Frost Bank, a regional bank in Texas for 26 years, of which he served as an Executive Vice President for 10 years. Mr. Donahoe is a graduate of Texas Tech University with over 30 years of commercial banking experience. Mr. Donahoe previously served as Board Chair of both the Health Alliance for Austin Musicians and the Real Estate Council of Austin. Mr. Donahoe's over 30 years of banking experience, combined with his leadership and management skills, qualify him to be a member of the Board.
H. J. SHANDS, III (70) – Mr. Shands retired on April 30, 2020 as Southside Regional President, East Texas, a role he held since the acquisition of Diboll State Bancshares, Inc. by the Company on November 30, 2017. He previously served as President and CEO of First Bank & Trust East Texas for 26 years and was Treasurer of Temple Inland Inc., a major manufacturer of corrugated packing and building products, with diversified banking and financial services operations. Mr. Shands served as Vice Chairman of the Finance Commission of Texas where he represented the banking industry for 8 years. He is a Trustee for the Marguerite Fairchild Foundation and previously served as a Trustee for the T.L.L. Temple Foundation. He is currently a director for Contractor's Supply Inc. He also served on the Board of Directors and was Past Chairman for CHI Memorial Health Center of East Texas, City of Lufkin 4B Economic Development and First Bank of Conroe, N.A. Mr. Shands' over 40 years of banking experience, leadership, business development and management skills qualify him to be a member of the Board.
PRESTON L. SMITH (70) – Mr. Smith has been the President and owner of PSI Production, Inc., a petroleum exploration and production company since 1985. He is a member of the Independent Petroleum Association of America and served as Northeast Texas Representative to the Board of Directors from 1999 to 2005. Mr. Smith is a managing member of Wildwood Environmental Credit Company, which serves as the conservation steward for over 40,000 acres of protected, high value ecosystems including the Pineywoods Mitigation Bank. Mr. Smith served on the Board of Trustees for All Saints Episcopal School of Tyler from 1994 to 2014, is a member of the Board of Trustees of the McCallie School in Chattanooga, TN., a former Chairman of the Board of CHRISTUS Trinity Mother Frances Health System and a member of the University of Texas at Tyler Engineering School Advisory Board. Mr. Smith’s management and leadership skills, combined with his knowledge of the oil and gas industry, emerging environmental credit markets and the healthcare industry qualify him to be a member of the Board.
NOMINEE FOR DIRECTOR TERM TO EXPIRE AT THE 2028 ANNUAL MEETING
JEB W. JONES (53) – Mr. Jones is the CEO of Pro Star Rental, a multi-site equipment rental company in Texas, a spin-off of the Cassity Jones Companies in 2015 through Pro Star Capital LP, in which he serves as President and General Partner. Prior to the spin off, he served as the Chief Operating Officer of the Cassity Jones Companies, a portfolio of real estate supply and service companies, which included building material supply, flooring, commercial construction, and commercial real estate, from 2009 to 2015. Mr. Jones began his career in management consulting and financial valuation before joining Tenet Healthcare, where he held various management positions throughout Texas from 2002 to 2009, including Chief Operating Officer of Nacogdoches Medical Center. Mr. Jones has served on the boards of numerous organizations including: Vice Chair of the Christus Health Northeast Texas Region, Past Chair of Hospice of East Texas, Past Chair of the City of Tyler Planning and Zoning Commission and executive committee of The Texas Lyceum. He holds a BA in economics from Texas A&M University and an MBA from Harvard Business School. Mr. Jones commercial construction and real estate experience, combined with his knowledge of the healthcare industry and management skills qualify him to be a member of the Board.
NOMINEE FOR DIRECTOR TERM TO EXPIRE AT THE 2027 ANNUAL MEETING

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RAYMOND C. MCKINNEY, CPA (53) – Mr. McKinney is CEO and President of The Genecov Group, a real estate and oil & gas investment company based in Tyler, Texas, a position he has held since 2016. Prior to joining the Genecov Group in 2015, he served as a Partner at Gollob Morgan Peddy P.C., an East Texas public accounting firm, from 2013 to 2014, and held various senior positions with the accounting firm previously. Mr. McKinney currently serves as a member of the UT Health Tyler Board of Trustees, the UT Tyler Audit Committee and is a Past Chairman of the Tyler Economic Development Council. He is a graduate of Louisiana Tech University and a licensed Certified Public Accountant. Mr. McKinney will serve on the Company's Audit Committee and Risk Committee, and the Bank's Executive/Loan and Discount Committee and Compliance/IT/CRA Committee. Mr. McKinney’s management and leadership skills, combined with his knowledge of the commercial real estate and oil and gas industries and financial expertise, qualify him to be a member of the Board.
DIRECTORS CONTINUING UNTIL THE 2028 ANNUAL MEETING
SHANNON DACUS (57) – Ms. Dacus is president and owner of the Dacus Firm, a minority and female-owned law firm in Tyler, Texas. She has been practicing law since 1994, with a focus on commercial litigation. She is past president of the Tyler Area Chamber of Commerce, the Tyler Economic Development Council, and the CHRISTUS Northeast Texas Health System boards of directors. She served on the board of an East Texas bank for almost 5 years, where she served as a member of the Audit Committee and Chair of the Risk and Compliance Committee. Ms. Dacus holds the distinction of being the first Hispanic female to chair the boards of the Tyler Area Chamber, the Texas Bar Foundation and the Tyler Economic Development Council, among others. She has received numerous honors, including the T.B. Butler Distinguished Citizen Award, the Adelante Award from the Hispanic Business Alliance, and the Legacy of Service Award from Women in Tyler. Ms. Dacus' legal background, business management experience, and leadership skills qualify her to be a member of the Board.
ALTON L. FRAILEY (64) – Mr. Frailey is President of Alton L. Frailey & Associates, LLC, specializing in leadership development, community engagement, school board team building, and executive coaching. Mr. Frailey earned his bachelor’s degree in Elementary Education and master’s degree in Educational Administration from Stephen F. Austin State University. He received his superintendent certification from the University of Texas at Tyler. Mr. Frailey has been involved in education for 43 years, serving most recently as the past superintendent for Katy Independent School District, as well as one other district in Texas and one in Ohio. Mr. Frailey served as past chair of the Stephen F. Austin State University Board of Regents, president of the American Association of School Administrators, the Texas Association of School Administrators, and the Urban Superintendents Association of America, as well as chairman of the University Interscholastic League Legislative Council. He served on the boards of directors for the Katy Area Chamber of Commerce, Katy Area Economic Development Council, Junior Achievement of Southeast Texas, West Houston Association and The Bible Seminary. Mr. Frailey has received numerous honors and awards including Texas Music Educators Association Distinguished Administrator, Region 4 Administrator of the Year, Who’s Who in Executives and Professionals, and the Trailblazer Award by South Dallas Business and Professional Women’s Club, Inc. Mr. Frailey's extensive executive experience and knowledge of leadership development, qualify him to be a member of the Board.
LEE R. GIBSON, CPA (69) – Mr. Gibson retired on December 31, 2025 as CEO of the Company and the Bank, a role he held since January 2017. He also previously served as President of the Company and the Bank from 2015 to 2024 and served as an executive and the Chief Financial Officer of the Company and the Bank from 2000 to 2015, and held various other roles throughout his career with the Company which began in 1984. He currently serves as President and Director of Bethesda Health Clinic, Director and Executive Committee Member of the Tyler Economic Development Council and a Board member of the R.W. Fair Foundation. He previously served as Chairman of the Board of Directors of the Federal Home Loan Bank of Dallas for six years, Council of Federal Home Loan Banks for two years, as well as a Director of the Texas Bankers Association. Mr. Gibson has over 40 years of banking experience, is a CPA and has extensive financial knowledge, which qualify him to be a member of the Board.
DIRECTORS CONTINUING UNTIL THE 2027 ANNUAL MEETING
S. ELAINE ANDERSON, CPA (73) – Ms. Anderson has a BBA with a major in accounting from Indiana University and has been a licensed CPA since 1976. She served as a director of OmniAmerican Bancorp from 1996 to December 17, 2014 and as independent Chairperson of the Board from May 2010 to December 17, 2014, when OmniAmerican Bancorp, Inc. (“OmniAmerican”) was acquired by the Company. She served for 24 years with Texas Health Resources as Senior Vice President and Chief Compliance Officer prior to retiring in January 2016. In that role, she had responsibilities for compliance, privacy, information security and enterprise risk management. Texas Health Resources is one of the largest nonprofit healthcare systems in the U.S. Her prior professional experience includes serving in various positions with the international accounting firm, PricewaterhouseCoopers from 1980 to 1991. Ms. Anderson served as the Treasurer for Arborlawn United Methodist Church Foundation for 30 years. Her memberships have included the American Institute of Certified Public Accountants, the Texas Society of Certified Public Accountants and the Health Care Compliance Association. Ms. Anderson's public accounting experience, understanding of financial statements and experience as the Chief Compliance Officer for a large healthcare system, qualify her to be a member of the Board.

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KIRK A. CALHOUN, M.D. (73) – Dr. Calhoun currently serves as President of the University of North Texas Health Science Center and previously served as President of The University of Texas (“UT”) at Tyler from 2002 until his retirement in 2024. Dr. Calhoun started his medical career in Internal Medicine private practice and subsequently pursued his passion in academic medicine. He has served in academic medical leadership positions for over 40 years, in many different roles including Corporate Medical Director of UT Medical Branch at Galveston (UTMB) HealthCare Systems, Senior Vice President of Parkland Hospital, the Associate Dean of Clinical Affairs at the UT Southwestern Medical School and subsequently serving a combined 22 years as President of UT at Tyler and The UT Health Science Center at Tyler. Dr. Calhoun also previously served as chairman of the board of directors for the UT Health East Texas Health System, and on the executive committee of Teaching Hospitals of Texas and is the immediate Past Chair of the American Association of Medical Colleges Board of Directors. Dr. Calhoun has received numerous awards for his work and leadership in healthcare, public health, higher education delivery and community service, including the prestigious Doctor Luke Society and the T.B. Butler Citizen of the Year Award in 2021. Dr. Calhoun’s extensive executive experience, combined with business management and leadership skills, qualify him to be a member of the Board.
PATRICIA A. CALLAN (67) – Ms. Callan is a principal of Callan Consulting, which has provided sales management, insurance, managed care and healthcare related consulting services in the Dallas/Fort Worth area since 2001. She previously held executive management positions in Texas and Kentucky for regional and national insurance companies and owned an independent insurance agency in Lexington, Kentucky. She also served on the Board of Directors of OmniAmerican from 2006 to December 17, 2014, when OmniAmerican was acquired by the Company. Ms. Callan holds a Texas General Lines License. Ms. Callan’s extensive business management and leadership experience qualify her to be a member of the Board.
JOHN R. (BOB) GARRETT (72) – Mr. Garrett is a residential and commercial real estate developer and has served as the President of Fair Oil Company, a Tyler based oil and gas exploration and production company, since 2002. Mr. Garrett is also President of the R. W. Fair Foundation and a member of the UT at Tyler Development Board. He is a former Chairman of the Board of Regents at Stephen F. Austin State University and a former member of the UT Tyler School of Medicine Admissions Committee. He is a past president of both the Tyler Area Builders Association and the Texas Association of Builders. Mr. Garrett brings to our Board extensive knowledge in the areas of residential and commercial real estate and oil and gas, as well as management, leadership and business skills and experience serving on numerous boards, all of which qualify him to be a member of the Board.

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EXECUTIVE OFFICERS
SHERRI ANTHONY (66) – Ms. Anthony currently serves as Chief Banking Officer of the Bank, a position she has held since January 2024. She joined the Bank in 2017, upon the acquisition of Diboll State Bancshares, Inc, where she served as Chief Compliance Officer with First Bank and Trust East Texas. Prior to her current role, she served as Senior Vice President and Retail Market Manager of the Bank from 2017 until December 2023. In her current role, she is responsible for retail banking in all of the Company's regions. Ms. Anthony is a graduate of the University of West Alabama and has over 40 years of banking experience. She is involved with the Salvation Army, Angelina Chamber of Commerce and Leadership Alumni Association.
T. L. ARNOLD, JR. (62) – Mr. Arnold currently serves as Chief Credit Officer (“CCO”) of the Company and of the Bank, as well as advisory director of the Bank. He previously served as Executive Vice President and Senior Credit Officer of the Bank from December 2014 until March 2019. He joined the Bank in December 2014, upon the acquisition of OmniAmerican Bank, where he served as Senior Executive Vice President and Chief Credit Officer. Mr. Arnold is a graduate of The University of Texas at Arlington and has over 40 years' experience in the banking and financial services industry. He serves on the Board of Directors for William Mann Community Development Corporation and is actively involved in Meals on Wheels of Tarrant County.
CURTIS R. BURCHARD (64) – Mr. Burchard currently serves as Chief Lending Officer (“CLO”) of the Company and of the Bank, a position he has held since June 2024, as well as advisory director of the Bank. He previously served as Senior Executive Vice President upon joining the Company in 2023. He previously served at Texas Capital Bank from 2018 to 2023, including positions as Head of Commercial Real Estate and Head of Real Estate (Commercial Real Estate and Homebuilding). In his current role, he is responsible for oversight of all lending activities in all of the Company's market areas. He has over 40 years of commercial banking experience.
MITCHELL CRADDOCK (45) – Mr. Craddock currently serves as Chief Operating Officer (“COO”) of the Company and of the Bank, a position he has held since November 2025. Upon joining the Bank in 2024, he served as Executive Vice President and Associate Chief Operations Officer of the Bank from August 2024 to November 2025. He previously served at Q2, a digital banking solutions company, from 2011 to 2024, and most recently as Vice President of Premier Services at Q2, where his role included creating vision and strategy for business development and streamlining processes and systems to drive revenue growth and improve operational efficiencies. He also previously served in various information technology and bank operations roles with the Bank from 2002 to 2011. Mr. Craddock has over 20 years of experience in the banking industry.
SUNI DAVIS, CPA (50) – Ms. Davis currently serves as Chief Treasury Officer (“CTO”) of the Company and the Bank, a position she has held since September 2024. Prior to her current role, she served as Chief Risk Officer from 2016 to 2024; and as Senior Vice President and Investment Officer prior to that. Ms. Davis obtained her BBA degrees in Finance and Accounting from the University of Texas at Tyler, is a Certified Public Accountant and holds a Certified Enterprise Risk Professional certification from the American Bankers Association. She joined the Bank in 1999 and is responsible for investment accounting, funds management, liquidity and interest rate risk. Ms. Davis is a member of the American Institute of Certified Public Accountants, the Texas Society of Certified Public Accountants (“TXCPA”) and the East Texas Chapter of the TXCPA.
KEITH M. DONAHOE (55) – Mr. Donahoe currently serves as President and CEO of the Company and the Bank, he has served as President of the Company and the Bank since May 2024 and CEO since January 2026. As Mr. Donahoe is also a director of the Company and the Bank, please see “NOMINEES FOR DIRECTOR TERMS TO EXPIRE AT THE 2029 ANNUAL MEETING” above for further biographical information with respect to Mr. Donahoe.
JARED GREEN (45) – Mr. Green currently serves as Regional President, East Texas, of the Bank, a position he has held since 2020. Prior to his current role, he served as Executive Vice President, Commercial Banking from 2013 to 2020. In his current role, he is responsible for strategic planning, coordination and implementation of lending operations in the East and Southeast Texas markets. Mr. Green obtained his BBA from Baylor University and his Masters in Finance from The University of Texas at Dallas. He has over 20 years of commercial banking experience. Mr. Green currently serves as a member of the Board of Trustees of The Brook Hill School and is a member of the Board of Trustees of Willow Brook Country Club.
ANNE MARTINEZ (51) – Ms. Martinez currently serves as Chief Risk Officer (“CRO”), of the Company and the Bank, a position she has held since September 2024. Prior to her current role, she served as Executive Vice President and Senior Loan Review Officer from 2012 to 2024. In her current role, she is responsible for enterprise risk management. Ms. Martinez obtained a BBA degree in Finance and Accounting from Texas A&M University. She joined Southside in 1999 and has over 28 years of banking and credit experience. Ms. Martinez currently serves on Moody's Community Banking Advisory Board and as Vice Chairman of the Texas A&M University Commercial Banking Program Board.

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APRIL PINKLEY, CPA (55) – Ms. Pinkley currently serves as Chief Accounting Officer (“CAO”), of the Company and the Bank, a position she has held since September 2024. Prior to her current role, she served as Controller of the Company since 2010, and as an Executive Vice President since 2023. Ms. Pinkley earned a BBA degree in accounting from UT Tyler and has over 20 years of banking experience. In her current role, she is responsible for the oversight of accounting, accounts payable and payroll departments. Ms. Pinkley is a member of the American Institute of Certified Public Accountants, the TXCPA and the East Texas Chapter of the TXCPA. She previously served on the Finance Committee of the United Way of East Texas and the board of The Rock of Living Water Ministry.
JULIE N. SHAMBURGER, CPA (63) – Ms. Shamburger currently serves as Chief Financial Officer (“CFO”) of the Company and the Bank, a position she has held since 2016. She is also an advisory director of the Bank. Ms. Shamburger served as Executive Vice President and Chief Accounting Officer from 2011 until April 2016. Ms. Shamburger joined the Bank in 1982 and has over 40 years of accounting experience. Ms. Shamburger is a graduate of the University of Texas at Tyler. Ms. Shamburger provides oversight to the Bank's funds management and investor relations. She is also responsible for the oversight of regulatory and Securities and Exchange Commission ("SEC") reporting as well as the daily accounting practices of the Company and the Bank. She currently serves as a member of the Board of Directors of Alzheimer's Alliance of Smith County. Ms. Shamburger is a member of the American Institute of Certified Public Accountants, the TXCPA and the East Texas Chapter of the TXCPA.

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CORPORATE RESPONSIBILITY

Since Southside first opened our doors in 1960, we have remained deeply committed to serving our communities and stakeholders. Our mission to bring prosperity, security and wealth to the people and businesses of Texas drives us to a culture of thoughtful and responsible action. We are committed to operating responsibly for the betterment of our business, communities and stakeholders.

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						Team Members

Team Members are our greatest asset, and the success of our business depends on our team and our ability to attract, retain and develop team members. We are deeply committed to our team members and are focused on the well-being and personal and professional development of our team members through our many corporate development initiatives including: corporate mentorship program, bank-wide professional coaching, leadership and training programs and team member recognition awards. We have a designated training department and maintain extensive training programs from entry level to manager level. During 2025, team members completed over 26,000 training hours in person and virtually.

Our “Southside Serves” volunteer program allows full-time team members to volunteer up to 20 hours of paid time off (“PTO”) each year with an approved organization of their choice. We believe this program not only strengthens our team members and communities but also reflects our strong corporate culture.

We offer a broad range of benefits including, but not limited to, 15-30 days of annual PTO based on length of employment, sick leave, participation in our Employee Stock Ownership Plan (“ESOP”) and adoption and educational reimbursement. In 2026, we implemented a Paid Parental Leave Benefit, which enhanced the paid leave benefits previously provided to eligible team members to care for their newborn or newly adopted child.

In 2025, we were recognized as a "Best Bank to Work For" by American Banker, for the fourth consecutive year, named one of the "Best Companies to Work For in Fort Worth" by Fort Worth, Inc. for the third consecutive year, and for the first time, recognized as one of the "Best Places to Work in Texas" by the Best Companies Group. These awards identify organizations that excel at creating positive and supportive workplaces for team members.


						Community

We have a rich history of community involvement and take great pride in serving the communities in which we operate. Our commitment to these communities is reflected through charitable contributions, community service, financial education programs and community development initiatives. In 2025, we donated over $1.1 million, our team members volunteered over 7,000 hours benefiting the communities we serve and approximately $697 million in Community Development loans were originated.

In 2025, we conducted financial empowerment sessions at a local community college, reaching over 600 students, hosted a financial literacy event at a local school, in which over 200 students and family members attended, and participated in a mentorship program for an economically disadvantaged school, mentoring on leadership and financial empowerment.

We are proud to have received the Texas Bankers Association Cornerstone Award in 2025, which honors Texas Banks with remarkable efforts for the betterment of their communities.


						Governance

We believe good governance practices and decision making are the foundation of operating responsibly and necessary for creating long-term shareholder value. We seek to follow best governance practices and maintain Corporate Governance Guidelines, which can be accessed on the Company’s website at https://southside.com/governance. Our Board is currently 86% independent, and we maintain an independent Chairman of the Board. All committees of the Company Board have female representation and females serve as Chairpersons of the Audit Committee and Corporate Governance and Nominating Committee. We are committed to Board refreshment. The Board has a policy regarding term limits, which requires Board members to retire on the date of the next Annual Meeting of Shareholders following their 75th birthday.

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						Cybersecurity

We have a dedicated Information Security Department (the “Department”), which is led by our Chief Information Security Officer (“CISO”), who reports directly to the CRO. The Department serves to protect the security and confidentiality of customer information, protect against any threats or hazards to the security or integrity of Company information and protect against unauthorized access to, or use of, such information that could result in substantial harm or inconvenience to our customers. For a further discussion of cybersecurity, as well as related risks, risk management strategies and governance, please see “Part I - Item 1C. Cybersecurity” in our Form 10-K, filed with the SEC on February 27, 2026.

During 2025, in addition to on-going training and awareness for team members, the Department facilitated a Cybersecurity awareness month, in which team members completed training sessions and interactive games on information security best practices including: strong passwords, security awareness, mobile device security, social media and reporting incidents. More than 8,000 hours of cybersecurity training were completed by employees during 2025. In addition, the Board completed various training sessions on Information Security, including a training session hosted by the CISO.


						Sustainability

We believe operating sustainably creates long-term value for our customers, communities and shareholders through reducing risks, strengthening our communities and helping us meet expectations of our stakeholders. We practice being a good steward of our resources through several initiatives including: enhancing, upgrading and building our facilities with environmental impact in mind; adopting various energy-efficient updates; offering an assortment of digital banking solutions to customers; and shredding and recycling paper through third party vendors. We have an Environmental Policy Statement, which outlines our commitment to environmental stewardship and operating responsibly, as well as efforts to support this commitment. Our Environmental Policy Statement is available on the Company’s website at https://southside.com/governance.

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CORPORATE GOVERNANCE

Board Leadership Structure

Our Board functions in a collaborative fashion that emphasizes active participation by all members. Our business is conducted day-to-day by our officers, under the direction of our President and CEO, Keith M. Donahoe, with oversight from the Board, to enhance the long-term value of the Company for its shareholders. Mr. Donahoe also serves as a member of the Board, which enables him to communicate the Board's strategic findings and guidance to management. Our Board determines who to appoint as our Chairman based on the knowledge and experience of the members then serving on our Board and chooses the person whom it believes best meets the needs of the Company. Both the Chairman and the Vice Chair are independent directors and serve as ex-officio members of the Audit, Corporate Governance and Nominating, Compensation, Risk, and Innovation, Digital Banking and Information Technology Committees.

Board Oversight of Risk

The Board recognizes that, although day-to-day risk management is primarily the responsibility of the Company’s management team, the Board plays a critical role in the oversight of risk. The Board believes an important part of its responsibility is to assess the major risks the Company faces and review the Company’s options for monitoring and controlling these risks. The Board assumes responsibility for the Company’s overall risk assessment, primarily through the Board's Audit and Risk Committees. The Audit Committee has specific responsibility for oversight of risks associated with financial accounting and audits, as well as internal control over financial reporting. This includes the Company’s risk assessment and management policies, the Company’s major financial risk exposure and the steps taken by management to monitor and mitigate such exposures. The Risk Committee assists the Board in fulfilling its responsibility for overseeing and improving the Company's enterprise-wide risk management practices, which includes ensuring that the executive team has identified and assessed the key risks the Company faces and has established a risk management infrastructure capable of addressing those risks. The Compensation Committee oversees the risks relating to the Company’s compensation policies and practices, as well as management development and leadership succession in the Company’s various business units, in conjunction with the Corporate Governance and Nominating Committee. The Innovation, Digital Banking and Information Technology Committee oversees risks related to technology and provides oversight for the Company's innovation and digital banking initiatives. The Board as a whole examines specific business risks including but not limited to credit risk, interest rate risk and operations risk, in its regular strategic reviews on a Company-wide basis.

In addition to periodic reports from the Audit, Risk, Corporate Governance and Nominating, Compensation, and Innovation, Digital Banking and Information Technology Committees about the risks over which they have oversight, the Board receives presentations throughout the year from management that include discussions of significant risks specific to the Company and the banking industry. Periodically, at Board meetings, management discusses matters of particular importance or concern, including any significant areas of risk requiring Board attention. We believe our risk oversight is also supported by our current Board leadership structure, with the Chairman of the Board working together with the independent Audit and Risk Committees and other standing committees.

Independent Directors

The Company’s common stock is listed on the New York Stock Exchange ("NYSE") and NYSE Texas, Inc. under the symbol “SBSI.” NYSE listing rules require a majority of our directors to be “independent directors,” as defined in the NYSE listing rules. The Board has affirmatively determined that all of the Company’s current directors, other than Keith M. Donahoe and Lee R. Gibson, are independent directors under the NYSE listing rules. Each member of the Board’s Audit, Corporate Governance and Nominating and Compensation Committees qualifies as an independent director, and all other Board committees are comprised of a majority of independent directors. All Board committees are chaired by independent directors.

Board of Directors Meeting Attendance

During 2025, each of our directors attended at least 75% of the aggregate of (1) the total number of meetings of the Board (held during the period for which he or she served as a director) and (2) the total number of meetings held by all committees of the Board on which he or she served (during the periods that he or she served). All of the Company’s directors were in attendance at the Company’s 2025 Annual Meeting. Although the Company has not adopted a formal written policy with respect to director attendance at meetings, we encourage our directors to attend each Annual Meeting of Shareholders and all meetings of the Board and committees on which the directors serve. Annually, directors acknowledge their commitment to attend 75% of board meetings, including committee meetings.

Meetings of Non-Management Directors

The Board meets periodically in scheduled executive sessions with non-management directors. The Chairman of the Board, H. J. Shands, III, who is an independent director, presides over executive sessions.

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Communication with the Board of Directors

Shareholders, employees or other interested parties may send communications to one or more members of the Board by writing to such director(s) or to the Board as a whole in care of the Corporate Secretary, Southside Bancshares, Inc., 1201 South Beckham Avenue, Tyler, Texas 75701. Any such communications will be promptly distributed by the Corporate Secretary to such individual director(s) or to all directors if addressed to the Board as a whole.

Code of Business Conduct and Ethics

The Company has adopted a Code of Business Conduct and Ethics (the “Code”) applicable to all directors, officers and employees of the Company and its subsidiaries. The Code is available on the Company’s website at https://southside.com/governance. Within the time period required by the Securities and Exchange Commission (“SEC”) and NYSE, we will post on our website any amendment to the Code and any waiver applicable to any of our directors, executive officers or senior financial officers. We include our website address throughout this filing only as textual references. The information contained on our website is not incorporated into this proxy statement by reference.

Procedures for Reporting Concerns including Accounting, Internal Accounting Controls or Auditing Matters

Management of the Company has established a Whistle Blower Policy, which includes an online reporting system available for reporting concerns, including accounting, internal accounting controls and audit matters, 24-hours, seven-days-a-week. This is a confidential service by which officers and employees can report to an independent company any issues or concerns, including human resource matters, or any questionable accounting or auditing matters, including, but not limited to, the following: fraud or deliberate error in the preparation, evaluation, review or audit of any financial statement of the Company; fraud or deliberate error in the recording and maintenance of financial records of the Company; deficiencies in or noncompliance with the Company’s internal accounting controls; misrepresentation or false statement to or by a senior officer or accountant regarding a matter contained in the financial records, financial reports or audit reports of the Company; or deviation from full and fair reporting of the Company’s financial condition. Human resource complaints are reported directly to the Human Resource Director; all other complaints are reported directly to the Chair of the Audit Committee and to the Chief Audit Executive of the Company, and will be reviewed by Internal Audit under the direction of the Audit Committee. All complaints submitted will be promptly investigated and appropriate corrective action will be taken, as warranted by the investigation. Management is committed to complying with all applicable securities laws and regulations and, therefore, encourages officers and employees to raise any issues or concerns by using the anonymous online reporting system.

Insider Trading Policy

The Company has adopted an insider trading policy governing the purchase, sale and/or other dispositions of its securities by directors, officers and employees, that is reasonably designed to promote compliance with insider trading laws, rules and regulations and any applicable listing standards. It is also the policy of the Company to comply with all applicable securities laws when transacting in its own securities. Our insider trading policy is available as Exhibit 19 to our Form 10-K for the year ended December 31, 2025, filed with the SEC on February 27, 2026.

Anti-Hedging and Anti-Pledging Policy

The Company maintains an anti-hedging and anti-pledging policy, which prohibits executive officers, directors and employees who receive equity grants from (1) directly or indirectly engaging in any hedging or monetization transactions, such as exchange funds, prepaid variable forward contracts, equity swaps, puts, calls, collars, forward sale contracts and other derivative instruments, through transactions in the Company’s securities or through the use of financial instruments designed for such purpose, (2) engaging in short sale transactions in the Company’s securities or (3) pledging the Company’s securities as collateral for a loan, including through the use of traditional margin accounts with a broker.

The Company maintains this policy to prevent the appearance of a person trading based on inside information, as hedging transactions might be considered short-term bets and a margin sale or foreclosure sale could occur at a time when the pledger is aware of nonpublic information or during a blackout trading period. In addition, transactions in options may also focus the person’s attention on short-term performance at the expense of the Company's long-term objectives.

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BOARD COMMITTEES

Southside Bancshares, Inc. Board Committees

The Board has five standing committees:

•Audit Committee;

•Compensation Committee;

•Innovation, Digital Banking and Information Technology Committee;

•Corporate Governance and Nominating Committee; and

•Risk Committee.

Each of the Committees of the Company's Board have a formal written charter, which can be found on the Company’s website at https://southside.com/governance.

Southside Bank Board Committees

The Southside Bank Board has five standing committees:

•Executive Committee;

•Loan/Discount Committee;

•Trust Committee;

•Compliance/IT/CRA Committee; and

•Investment/Asset-Liability Committee (ALCO).

The following table presents the compositions of the Committees of both the Company's Board and the Southside Bank Board, as well as the number of meetings held, for the year ended December 31, 2025:

Directors

Southside Bancshares, Inc.

Southside Bank

Independent

Board

Committees

Board

Committees

Audit

Compensation

Innovation, Digital Banking and Information Technology

Corporate Governance and Nominating

Risk

Executive/ Loan and Discount

Trust

Compliance / IT / CRA

ALCO

Lawrence L. Anderson, M.D.

S. Elaine Anderson, CPA

Michael J. Bosworth

Kirk A. Calhoun, M.D.

Patricia A. Callan

Shannon Dacus

Keith M. Donahoe

Alton L. Frailey

John R. (Bob) Garrett

Lee R. Gibson, CPA

Jeb W. Jones

Raymond C. McKinney, CPA

H. J. Shands, III

Preston L. Smith

Meetings during 2025


C			Chair
VC			Vice Chair
B			Serves as a Bank officer, which is a non-voting committee member.

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These committees were formed to assist the boards of directors of the Company and the Bank in the discharge of their respective responsibilities. The purpose and composition of these committees is described below.

Audit Committee of Southside Bancshares, Inc.

The Audit Committee of the Board was established in accordance with Section 3(a)(58)(A) of the Securities Exchange Act of 1934, as amended, or the Exchange Act. The Corporate Governance and Nominating Committee of the Board has unanimously determined that S. Elaine Anderson, CPA and Raymond C. McKinney, CPA, who both served in 2025, each qualify as an “audit committee financial expert” as defined by the SEC. The Corporate Governance and Nominating Committee of the Board has also unanimously determined that all Audit Committee members are financially literate under the current NYSE listing rules.

The Audit Committee is primarily responsible for the engagement of the Company's independent registered certified public accounting firm, oversight of the Company’s financial statements and controls, assessing and ensuring the independence, qualifications and performance of the independent registered certified public accounting firm, approving the services and fees of the independent registered certified public accounting firm and reviewing and approving the annual audited financial statements of the Company before issuance, subject to the approval of the Board. The Audit Committee manages the Company’s relationship with its independent registered certified public accounting firm, who reports directly to the Audit Committee. The Audit Committee also monitors the internal audit function, internal accounting procedures and assures compliance with all appropriate statutes and regulations. The Audit Committee has the authority to obtain advice and assistance from outside legal, accounting or other advisors as the Audit Committee deems necessary to carry out its duties, with funding from the Company for such advice and assistance. No members of the Audit Committee received any compensation from the Company during the last fiscal year other than directors’ fees. The Audit Committee reviews the Audit Committee charter on an annual basis.

Corporate Governance and Nominating Committee of Southside Bancshares, Inc.

The Corporate Governance and Nominating Committee is responsible for identifying, screening and recommending candidates for election to the Board and seeks to create a Board that is, as a whole, strong in its collective knowledge and diversity of skills and experience and background with respect to accounting and finance, management and leadership, business judgment, industry knowledge and corporate governance. When the Corporate Governance and Nominating Committee reviews a potential new director candidate, it looks specifically at the candidate’s qualifications in light of the current and future needs of the Board and the Company at that time, in conjunction with the existing mix of director attributes.

The Board has established the following process for the identification and selection of candidates for director. The Corporate Governance and Nominating Committee annually reviews the appropriate experience, skills and characteristics required of Board members in the context of the current membership of the Board to determine whether the Board would be better enhanced by the addition of one or more directors. In considering board of director candidates, the Corporate Governance and Nominating Committee takes into consideration all factors that it deems appropriate, including, but not limited to, the individual’s character, education, experience, knowledge, skills and ownership of the Company’s stock. The Corporate Governance and Nominating Committee will also consider the extent of the individual’s experience in business, education or public service, his or her ability to bring a desired range of skills, diverse perspectives and experiences to the Board and whether the individual possesses high ethical standards, a strong sense of professionalism and is capable of serving the interests of the Company's shareholders. A candidate should possess a working knowledge of the Company’s current local market areas. Additionally, the Corporate Governance and Nominating Committee will consider the number of boards the candidate currently serves on when assessing whether the candidate has the appropriate amount of time to devote to serving on the Company’s Board.

The Corporate Governance and Nominating Committee identifies candidates to the Board by introduction from management, members of the Board, employees or other sources, and shareholders that satisfy the Company’s policy regarding director candidates recommended by shareholders. The Corporate Governance and Nominating Committee does not evaluate director candidates recommended by shareholders differently than director candidates recommended by other sources. Shareholders wishing to submit director candidate recommendations for the 2027 Annual Meeting should write to the Corporate Governance and Nominating Committee in care of the Corporate Secretary, Southside Bancshares, Inc., Post Office Box 8444, Tyler, Texas 75711. Any such shareholder must follow the procedures set forth in the Company’s bylaws and the Corporate Governance and Nominating Committee charter. Our bylaws provide that proposals that comply with all rules and requirements of the SEC and are included in our proxy statement are deemed to comply with the advance notice procedures in our bylaws. Shareholder director recommendations must be submitted to the Corporate Secretary on or before November 25, 2026, in order to be included in the proxy statement for the 2027 Annual Meeting. See “Shareholder Proposals.” The Corporate Governance and Nominating Committee is not obligated to recommend any individual proposed by a shareholder as a nominee for election to the Board. No shareholder recommendations have been received by the Company for this Annual Meeting. Accordingly, no rejections or refusals of such candidates have been made by the Company.

In addition, the Corporate Governance and Nominating Committee is responsible for identifying, screening and recommending to the Board candidates to serve on the Compensation Committee, Audit Committee, Risk Committee and Innovation, Digital Banking and Information Technology Committee. These recommendations are submitted to the Board for final approval.

Compensation Committee of Southside Bancshares, Inc.

The Compensation Committee of the Board reviews the Company’s general compensation philosophy and oversees the development of compensation and benefit programs. The Compensation Committee recommends the compensation for the

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named executive officers of the Company, all of whom are executive officers of the Company and the Bank. The boards of directors of the Company and the Bank consider the recommendations of the Compensation Committee and approve the compensation of the named executive officers. The Committee also reviews and develops recommendations for all director compensation. Pursuant to its charter, which is reviewed by the Committee annually, the Compensation Committee may form and delegate authority and duties to subcommittees as it deems appropriate. Additional information regarding the Compensation Committee’s processes and procedures for consideration of executive compensation is provided in the Compensation Discussion and Analysis below.

Risk Committee of Southside Bancshares, Inc.

The purpose of the Risk Committee is to assist the Board in fulfilling its oversight responsibilities with regard to the risk appetite of the Company, enterprise-wide risk management, the Company's compliance framework and the governance structure that supports it. The primary responsibility of the Risk Committee is to oversee and improve company-wide risk management practices while assisting the Board by:

•Ensuring that the executive team has identified and assessed the key risks the Company faces and has established a risk management infrastructure capable of addressing those risks;

•Overseeing, in conjunction with other Board-level committees or the full Board, if applicable, risks, such as strategic, financial, credit, liquidity, information security, operational, information technology, legal, model, third party, regulatory, interest rate, reputational and other risks;

•Overseeing the division of risk-related responsibilities to each Board committee as clearly as possible and performing a gap analysis to determine the full oversight of all risks; and

•Approving, in conjunction with the full Board, the Company’s enterprise-wide risk management framework.

In addition to the Company's Board members specified above, also serving on the committee is Anne Martinez, CRO, of the Company and the Bank.

Innovation, Digital Banking and Information Technology Committee of Southside Bancshares, Inc.

The purpose of the Innovation, Digital Banking and Information Technology Committee is to assist the Board in fulfilling its oversight responsibilities with regard to innovation, digital banking and information technology. Specific responsibilities of this committee are:

•Provide oversight on IT strategies and subjects related to digital innovation, digital banking strategies, products and business/IT;

•Review management reports and provide oversight of the implementation of major digital banking, technology innovation and business/IT projects and architecture decisions;

•Review the IT plan which demonstrates objectives and targets for digital banking, technology innovation and business/IT risks, proposals and acquisition processes; and

•Ensure the Company’s digital banking, digital innovation and business/IT programs effectively support its business objectives and strategies.

In addition to the Company's Board members specified above, also serving on the committee are bank officers Sherri Anthony, Faye Bond, Jason Cathey, Mitchell Craddock, Eddie Crawford, Suni Davis, Justin Hutcheson, Keith Leonhardt, Anne Martinez, Mary McLarry, Gary Mills, Chris Phelps, Carlos Renteria, Gordon Roberts, Leigh Anne Rozell, James Schafer, Julie N. Shamburger and Lora Stockhammer.

Southside Bancshares, Inc. | 2026 Proxy Statement | 16

COMMITTEES OF SOUTHSIDE BANK

Executive Committee and Loan/Discount Committee of Southside Bank

The Executive Committee is authorized to act on behalf of the Board of Directors of the Bank between scheduled Board meetings, subject to certain limitations. The members of the Executive Committee comprise the Loan/Discount Committee of the Bank. It is the Loan/Discount Committee’s responsibility to monitor credit quality, review extensions of credit and approve selected credits in accordance with the loan policy.

In addition to the Company's Board members specified above, also serving on the committee as an advisory director of the Bank is T. L. Arnold, Jr., CCO.

Trust Committee of Southside Bank

The Trust Committee of the Bank is responsible for the oversight of the operations and activities of the Wealth Management and Trust Department. In addition to the Company's Board members specified above, also serving on this committee as advisory members are Julie N. Shamburger and Lonny Uzzell. Officers of the Bank who serve on the committee include Kim Christie, Emily Corbett, Bill Newburn and Hilary Walker.

Compliance, IT and Community Reinvestment Act (CRA) Committee of Southside Bank

The Compliance/IT/CRA Committee of the Bank is responsible for ensuring compliance with all appropriate statutes and reviews IT and community reinvestment activities. The Compliance/IT/CRA Committee is comprised solely of persons who are directors of the Company and the Bank but who are not officers or employees.

Investment/Asset-Liability Committee (ALCO) of Southside Bank

The Investment/Asset-Liability Committee is responsible for reviewing the Bank’s overall asset and funding mix, asset-liability management policies and investment policies. In addition to the Company's Board members specified above, officers serving on this committee include T. L. Arnold, Jr., Curtis R. Burchard, Suni Davis, Kyle Gibson, Jared Green, Robby Plymail, Julie N. Shamburger and Lonny Uzzell.

Southside Bancshares, Inc. | 2026 Proxy Statement | 17

DIRECTOR COMPENSATION

DIRECTOR COMPENSATION PROGRAM

The Board adopted a Director Compensation Program (the “Director Program”) for compensating non-employee directors of the Company for their time, commitment and contributions to the Board, including each non-employee’s service on the board of the Bank. Under the Director Program, non-employee directors are paid an annual retainer of $101,000, which is payable in quarterly installments, for each year of his or her service on the Board (each, a “Service Year”). Each Service Year commences on the date of the Company’s Annual Meeting at which Board members are elected or appointed. Employee directors do not receive compensation for service on the Company's Board or the board of the Bank.

In addition to the annual retainer, the following positions received an additional retainer for the 2025 service year as follows:


Position	Additional Retainer
Chairman	$	48,500
Vice Chair	$	23,500
Audit Committee Chair	$	23,500
Compensation Committee Chair	$	12,500
Risk Committee Chair	$	12,500
Asset-Liability Committee Chair	$	7,500
Innovation, Digital Banking and Information Technology Committee Chair	$	7,500
Trust Committee Chair	$	7,500
Corporate Governance and Nominating Committee Chair	$	5,000

The Director Program provides that non-employee directors will receive at least 40% of their annual retainer in the form of restricted stock units (“RSUs”), with the balance payable in cash in quarterly installments. In addition, directors may elect to receive a larger percentage (up to 100%) of their annual retainer and additional retainers, as applicable, in the form of RSUs. The RSUs are granted on or about the first day of the Service Year and have a value on the grant date approximately equal to the amount of the annual cash retainer and/or additional retainer payments that he or she has elected to receive in the form of RSUs. The RSUs vest (become non-forfeitable) on the first anniversary of the grant date (or, if earlier, on the date of the Company’s Annual Meeting that occurs in the year immediately following the year of grant, in the event Grantee is not standing for re-election to the Board at such Annual Meeting) (with accelerated vesting on a pro rata basis in the event of death, disability or a change in control of the Company). Directors may elect to receive shares of common stock in settlement of their RSUs on the vesting date, or they may elect to defer the receipt of such shares and instead receive them on a specified anniversary of the grant date or upon termination of their service on the Board (subject, in each case, to earlier settlement upon a change in control of the Company).

Southside Bancshares, Inc. | 2026 Proxy Statement | 18

2025 DIRECTOR COMPENSATION

The table below summarizes the compensation earned by the Company's directors for the year ended December 31, 2025. Lee R. Gibson, the Company’s Former CEO, through his retirement on December 31, 2025, as well as Keith M. Donahoe, President and current CEO, are not included in the table below, as they were officers of the Company during 2025, and thus received no compensation for their service as a director during 2025. Mr. Gibson's and Mr. Donahoe's compensation amounts are shown in the Summary Compensation Table under Executive Compensation.


Name	Fees Earned or Paid in Cash ($) (1)		Stock Awards ($) (2)		All Other Compensation ($)		Total ($)
Lawrence L. Anderson, M.D. (3)	$	55,656	$	54,239	$	—	$	109,895
S. Elaine Anderson, CPA (4)	79,975		40,389		—		120,364
Michael J. Bosworth (5)	39,406		60,599		—		100,005
Kirk A. Calhoun, M.D. (6)	64,506		46,631		—		111,137
Patricia A. Callan (7)	65,288		40,389		—		105,677
Shannon Dacus (8)	63,725		40,389		—		104,114
Alton L. Frailey (9)	33,063		75,727		—		108,790
John R. (Bob) Garrett (10)	84,111		40,389		—

SEC Form DEF 14A filed by Southside Bancshares Inc.