Simmons First National : 4th Quarter 2021 Investor Presentation

| NASDAQ: SFNC

Contents

4 Q4 &2021 Highlights

5 Q4 Results Overview

13 Loans

18 Deposits, Liquidity, Securities,

Interest Rate Sensitivity &

Capital

24 Credit Quality

27 Key Takeaways and

Management Outlook

30 Appendix

4th Quarter 2021 Earnings Presentation

Forward-Looking Statements and Non-GAAP Financial Measures

Forward-LookingStatements.Certain statements by Simmons First National Corporation (the "Company", which where appropriate includes the Company's wholly-owned banking subsidiary, Simmons Bank) contained in this presentation may not be based on historical facts and should be considered "forward-looking statements" within the meaning of the Private Securities Litigation Reform Act of 1995. These forward-looking statements may be identified by reference to a future period(s) or by the use of forward-looking terminology, such as "anticipate," "estimate," "expect," "foresee," "project," "may," "might," "will," "would," "could," "likely" or "intend," future or conditional verb tenses, and variations or negatives of such terms. These forward-looking statements include, without limitation, those relating to the Company's future growth; revenue; expenses (including interest expense and non-interest expenses); assets; loan demand; asset quality; profitability; earnings; critical accounting policies; accretion; net interest margin; noninterest revenue; market conditions related to and impact of the Company's common stock repurchase program; adequacy of the allowance for loan losses; income tax deductions; credit quality; level of credit losses from lending commitments; net interest revenue; interest rate sensitivity (including, among other things, the potential impact of rising rates); loan loss experience; liquidity; capital resources; market risk; the expected benefits, milestones, timelines, and costs (and the anticipated realization of expected cost savings) associated with the Company's merger and acquisition strategy and activity; the Company's ability to recruit and retain key employees; the ability of the Company to manage the impacts of the COVID-19 pandemic; the impacts of the Company's and its customers participation in the Paycheck Protection Program ("PPP"); increases in the Company's security portfolio; legal and regulatory limitations and compliance and competition; anticipated loan principal reductions; fees associated with the PPP; plans for investments in securities; statements on the slides titled "Key Takeaways" and "Management Outlook"; the charges, gains, and savings associated with completed and future branch closures and branch sales; and projected dividends.

Readers are cautioned not to place undue reliance on the forward-looking statements contained in this presentation in that actual results could differ materially from those indicated in or implied by such forward-looking statements, due to a variety of factors. These factors include, but are not limited to, changes in the Company's operating or expansion strategy; the availability of and costs associated with obtaining adequate and timely sources of liquidity; the ability to maintain credit quality; the effect of steps the Company takes in response to the COVID-19 pandemic; the severity and duration of the pandemic, including the effectiveness of "booster" vaccination efforts and developments with respect to COVID-19 variants; the pace of recovery when the pandemic subsides and the heightened impact it has on many of the risks described herein; the effects of the pandemic on, among other things, the Company's operations, liquidity, and credit quality; general market and economic conditions; unemployment; possible adverse rulings, judgments, settlements and other outcomes of pending or future litigation; the ability of the Company to collect amounts due under loan agreements; changes in consumer preferences and loan demand; effectiveness of the Company's interest rate risk management strategies; laws and regulations affecting financial institutions in general or relating to taxes; the effect of pending or future legislation; the ability of the Company to repurchase its common stock on favorable terms; the ability of the Company to successfully manage and implement its acquisition and branch strategy and integrate acquired institutions; the ability to obtain regulatory approvals and meet other closing conditions to the proposed merger of Spirit of Texas Bancshares, Inc. ("Spirit") with and into the Company ("Proposed Transaction"); delay in closing the Proposed Transaction; difficulties and delays in integrating the acquired business or fully realizing cost savings and other benefits of the Proposed Transaction; changes in interest rates, deposit flows, real estate values, and capital markets; inflation; customer acceptance of the Company's products and services; changes or disruptions in technology and IT systems (including cyber threats, attacks and events); changes in accounting principles relating to loan loss recognition (current expected credit losses, or CECL); the benefits associated with the Company's early retirement program and branch closures and sales; and other risk factors. Other relevant risk factors may be detailed from time to time in the Company's press releases and filings with the U.S. Securities and Exchange Commission, including, without limitation, the Company's Form 10-K for the year ended December 31, 2020. Any forward-looking statement speaks only as of the date of this presentation, and the Company undertakes no obligation to update these forward-looking statements to reflect events or circumstances that occur after the date of this presentation. Annualized, pro forma, projected and estimated numbers are used for illustrative purpose only, are not forecasts and may not reflect actual results.

Non-GAAPFinancial Measures.This presentation contains financial information determined by methods other than in accordance with U.S. generally accepted accounting principles (GAAP). The Company's management uses these non-GAAP financial measures in their analysis of the Company's performance. These measures adjust GAAP performance measures to, among other things, include the tax benefit associated with revenue items that are tax-exempt, as well as exclude from income available to common shareholders, non-interest income, and non-interest expense certain income and expenses related to significant non-core activities, such as merger-related expenses, expenses related to the Company's early retirement program, gain on sale of branches, and net branch right-sizing expenses. In addition, the Company also presents certain figures based on tangible common stockholders' equity, tangible assets, and tangible book value, which exclude goodwill and other intangible assets. The Company further presents certain figures that are exclusive of the impact of PPP loans, as well as normalized core non-interest expense. The Company's management believes that these non-GAAP financial measure are useful to investors because they, among other things, present the results of the Company's ongoing operations without the effect of mergers or other items not central to the Company's ongoing business, as well as normalize for tax effects. Management, therefore, believes presentations of these non- GAAP financial measures provide useful supplemental information that is essential to a proper understanding of the operating results of the Company's core businesses, and management uses these non-GAAP measures to assess the performance of the Company's core businesses as related to prior financial periods. These non-GAAP disclosures should not be viewed as a substitute for operating results determined in accordance with GAAP, nor are they necessarily comparable to non-GAAP performance measures that may be presented by other companies. Where non-GAAP financial measures are used, the comparable GAAP financial measure, as well as the reconciliation to the comparable GAAP financial measure, can be found in the appendix to this presentation.

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Important Additional Information and Where to Find It

This communication does not constitute an offer to sell or the solicitation of an offer to buy any securities or a solicitation of any vote or approval with respect to the Proposed Transaction. No offer of securities shall be made except by means of a prospectus meeting the requirements of the Securities Act of 1933, as amended, and no offer to sell or solicitation of an offer to buy shall be made in any jurisdiction in which such offer, solicitation or sale would be unlawful.

In connection with the Proposed Transaction, the Company has filed with the SEC a registration statement on Form S-4 (the "Registration Statement") to register the shares of Company common stock that will be issued to Spirit shareholders in the Proposed Transaction. The Registration Statement includes a proxy statement of Spirit and a prospectus of the Company (the "Proxy Statement/Prospectus"), and the Company and/or Spirit may file with the SEC other relevant documents concerning the Proposed Transaction. The definitive Proxy Statement/Prospectus is being mailed to shareholders of Spirit. SHAREHOLDERS ARE URGED TO READ THE REGISTRATION STATEMENT AND THE PROXY STATEMENT/PROSPECTUS REGARDING THE PROPOSED TRANSACTION CAREFULLY AND IN ITS ENTIRETY WHEN IT BECOMES AVAILABLE AND ANY OTHER RELEVANT DOCUMENTS FILED WITH THE SEC BY THE COMPANY AND/OR SPIRIT, AS WELL AS ANY AMENDMENTS OR SUPPLEMENTS TO THOSE DOCUMENTS, BECAUSE THEY WILL CONTAIN IMPORTANT INFORMATION ABOUT THE PROPOSED TRANSACTION.

Free copies of the Proxy Statement/Prospectus, as well as other filings containing information about the Company and Spirit, may be obtained at the SEC's Internet site (http://www.sec.gov), when they are filed by the Company or Spirit. You will also be able to obtain these documents, when they are filed, free of charge, from the Company at simmonsbank.com under the heading "Investor Relations" or from Spirit at www.sotb.com under the "Investor Relations" link. Copies of the Proxy Statement/Prospectus can also be obtained, free of charge, by directing a request to the Company at Simmons First National Corporation, 501 Main Street, Pine Bluff, Arkansas 71601, Attention: Ed Bilek, Director of Investor Relations, Email: [e-mail] or [e-mail], Telephone: [phone]; or by directing a request to Spirit at Spirit of Texas Bancshares, Inc., 1836 Spirit of Texas Way, Conroe, Texas 77301, Attention: Corporate Secretary, Email: [e-mail], Telephone: [phone].

Participants in the SolicitationThe Company, Spirit, and certain of their respective directors, executive officers and employees may be deemed to be participants in the solicitation of proxies from the shareholders of Spirit in connection with the Proposed Transaction. Information about the Company's directors and executive officers is available in its proxy statement for its 2021 annual meeting of shareholders, which was filed with the SEC on April 15, 2021. Information about Spirit's directors and executive officers is available in its proxy statement for its 2021 annual meeting of shareholders, which was filed with the SEC on April 9, 2021. Information regarding all of the persons who may, under the rules of the SEC, be deemed participants in the proxy solicitation and a description of their direct and indirect interests, by security holdings or otherwise, will be contained in the Proxy Statement/Prospectus regarding the Proposed Transaction and other relevant materials to be filed with the SEC when they become available. Free copies of these documents may be obtained as described in the preceding paragraph.

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Q4 and 2021 Highlights

1	Includes the results of Landmark	Q4 21 EPS of		Full-year 2021 EPS of
		$2.46
Community	Bank and	Triumph	$0.42
Bancshares, Inc. acquisitions (closed on 10/8/21)
					Core EPS(1) of $0.52		up 6% vs 2020
	Green shoots	in loan	demand	Newly funded loans of	Commercial loan pipeline
	evidenced	by	widespread	growth	+56%vs Sept-21
	$2.6Bin Q4 21
	across the footprint, coupled with
2 activity in new business units	up 5th consecutive quarter
	Strong capital position and ability to	Dividends paid in 2021	Shares repurchased in 2021
	organically generate capital allows the	$78.8 million	$132.5million
3 return of excess capital to shareholders
	Share repurchase program substantially	New share repurchase plan		Book value per share of
	exhausted in Jan-22,Board authorizes	$175 million		$28.82, up 5 percent YoY
4 new share repurchase program(2) and a		Tangible book value(1) of
	6 percent increase in quarterly dividend	authorized		$17.71, up 7 percent YOY
	Significantly enhancing our position and	Expected closing, conversion	Regulatory filings
	and integration
	scale in Texas with the pending acquisition		S-4 filed on 12/22/21
	in 2022		FRB filing on 12/29/21
5 of Spirit of Texas Bancshares, Inc.
		S-4/A filed on 1/18/22
		S-4 effectiveness order 1/21/22
(1) Non-GAAP measures that management believes aids in the discussion of results. See Appendix for Non-GAAP reconciliation
(2)	Market conditions and our capital needs will drive the decisions regarding additional, future stock repurchases.		4
YoY - year-over-year

Note: Book value per share and tangible book value per share figures noted above are as of December 31, 2021

Q4 21 Results Overview

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