Southside Bancshares : 2023 Annual Meeting of Shareholders Presentation

NASDAQ/SBSI May 17, 2023

Forward-Looking Statements

• Certain statements of other than historical fact that are contained in this press release and in other written materials, documents and oral statements issued by or on behalf of the Company may be considered to be "forward-looking statements" within the meaning of and subject to the safe harbor protections of the Private Securities Litigation Reform Act of 1995. These forward-looking statements are not guarantees of future performance, nor should they be relied upon as representing management's views as of any subsequent date. These statements may include words such as "expect," "estimate," "project," "anticipate," "appear," "believe," "could," "should," "may," "might," "will," "would," "seek," "intend," "probability," "risk," "goal," "target," "objective," "plans," "potential," and similar expressions. Forward-looking statements are statements with respect to the Company's beliefs, plans, expectations, objectives, goals, anticipations, assumptions, estimates, intentions and future performance and are subject to significant known and unknown risks and uncertainties, which could cause the Company's actual results to differ materially from the results discussed in the forward-looking statements. For example, discussions of the effect of our expansion, benefits of the Share Repurchase Plan, trends in asset quality, capital, liquidity, the Company's ability to sell nonperforming assets, expense reductions, planned operational efficiencies and earnings from growth and certain market risk disclosures, including the impact of interest rates, tax reform, inflation, the impacts related to or resulting from Russia's invasion of Ukraine and other economic factors are based upon information presently available to management and are dependent on choices about key model characteristics and assumptions and are subject to various limitations. By their nature, certain of the market risk disclosures are only estimates and could be materially different from what actually occurs in the future. Accordingly, our results could materially differ from those that have been estimated. The most significant factor that could cause future results to differ materially from those anticipated by our forward-looking statements include the ongoing impact of higher inflation levels, higher interest rates and general economic and recessionary concerns, all of which could impact economic growth and could cause a reduction in financial transactions and business activities, including decreased deposits and reduced loan originations, our ability to manage liquidity in a rapidly changing and unpredictable market, supply chain disruptions, labor shortages and additional interest rate increases by the Federal Reserve.
• Additional information concerning the Company and its business, including additional factors that could materially affect the Company's financial results, is included in the Company's Annual Report on Form 10-K for the year ended December 31, 2022, under "Part I - Item 1. Forward Looking Information" and in the Company's other filings with the Securities and Exchange Commission. The Company disclaims any obligation to update any factors or to announce publicly the result of revisions to any of the forward-looking statements included herein to reflect future events or developments.

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A Year in Review

• Ended 2022 with excellent financial results, continued strong asset quality, an increase in our net interest margin and excellent cost control;
• Experienced record loan growth, reflectiveGoalsof theforstrong2023markets we serve;
• A recipient of the 2022 Raymond James Community Banker's Cup, awarded to the top 10% of community banks based on certain financial performance metrics;
• Introduced new technologies and innovative solutions for customers; and
• Awarded one of the "Best Banks to Work For" in 2022 by American Banker.

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Goals for 2023

• Maintain asset quality;
• Further enhance digital/technology strategies;
• Capitalize on operational processGoalsefficiency;for 2023
• Navigate changes in the banking industry;
• Dynamically manage interest rate risk; and
• Continued focus on organically growing loans & non- maturity deposits.

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Texas Bank Stock Performance

SBSI has performed better than the KBW Regional Banking Index (KRX) and Texas Banks when comparing 2023 stock performance through 5/12/2023

Texas Bank Stock Performance

MEAN(1)	5/12/2023 compared to 12/31/2022	(29.94)%
MEDIAN(1)	5/12/2023	12/31/2022	(27.46)%
KRX(2)
$	76.97	$	114.09	(32.54)%
SBSI	$	26.69	$	35.99	(25.84)%

1. Calculated for 15 Texas publically traded banks, including SBSI and the following: Hilltop Holdings, Inc. (HTH), Triumph Financial, Inc. (TFIN), Third Coast Bancshares, Inc. (TCBX), Prosperity Bancshares (PB), South Plains Financial (SPFI), Texas Capital Bancshares, Inc. (TCBI), Stellar Bancorp, Inc. (STEL), Cullen/Frost Bankers, Inc. (CFR), Guaranty Bancshares, Inc. (GNTY), Veritex Holdings, Inc. (VBTX), Independent Bank Group (IBTX), Comerica Incorporated (CMA), First Foundation, Inc. (FFWM).
2. KRX is the KBW Regional Banking Index is a modified-capitalization-weighted index, created by Keefe, Bruyette & Woods, designed to effectively represent the performance of the broad and diverse U.S. regional banking industry

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