Exhibit 99.1

July 17, 2025

Simmons First National Corporation Reports Second Quarter 2025 Results

George Makris, Jr., Simmons’ Chairman and CEO, commented on second quarter 2025 results:

We were pleased with our second quarter results which reflected strong revenue growth, disciplined expense management and positive underlying balance sheet growth that led to further improvement in profitability measures.

Our net interest margin increased for the fifth consecutive quarter and surpassed the 3 percent mark ahead of expectations. Loan yields were up and deposit costs declined for the third consecutive quarter. While overall balance sheet growth was muted, our loan pipeline remains strong and our focus on profitability as well as loan and deposit remixing resulted in C&I growth coupled with a $233.1 million increase in low-cost customer deposits. At the same time, asset quality metrics were stable.

While certain administration policies have become clearer, tariff volatility looms large and is a key to future interest rate moves and economic conditions. Against this backdrop, we continue our focus on organic growth in our very attractive footprint and are encouraged by our positive momentum heading into the last half of 2025.

Simmons First National Corporation (NASDAQ: SFNC) (Simmons or Company) today reported net income of $54.8 million for the second quarter of 2025, compared to $32.4 million in the first quarter of 2025 and $40.8 million in the second quarter of 2024. Diluted earnings per share were $0.43 for the second quarter of 2025, compared to $0.26 in the first quarter of 2025 and $0.32 for the second quarter of 2024. Adjusted earnings1 for the second quarter of 2025 were $56.1 million, compared to $33.1 million in the first quarter of 2025 and $41.9 million in the second quarter of 2024. Adjusted diluted earnings per share1 for the second quarter of 2025 were $0.44, compared to $0.26 in the first quarter of 2025 and $0.33 in the second quarter of 2024.

The table below summarizes the impact of certain items, consisting primarily of branch right sizing, early retirement program, FDIC special assessments and termination of vendor and software services. They are also described in further detail in the “Reconciliation of Non-GAAP Financial Measures” tables contained in this press release.

Impact of Certain Items on Earnings and Diluted Earnings Per Share (EPS)

Net Interest Income

Net interest income for the second quarter of 2025 totaled $171.8 million, up $8.4 million, or 5 percent, compared to $163.4 million in the first quarter of 2025 and up $17.9 million, or 12 percent, from $153.9 million in the second quarter of 2024. Interest income totaled $315.0 million for the second quarter of 2025, compared to $307.8 million in the first quarter of 2025 and $329.1 million in the second quarter of 2024. The increase in interest income on a linked quarter basis was primarily due to an increase in earning asset yields, principally loan yields, driven by disciplined pricing of new originations as well as positive fixed-rate loan repricing. Interest expense totaled $143.2 million for the second quarter of 2025, compared to $144.4 million in the first quarter of 2025 and $175.2 million in the second quarter of 2024. The decrease in interest expense on a linked quarter basis reflected management’s efforts to proactively manage deposit costs given maturing deposit repricing and remixing opportunities. Included in net interest income is accretion recognized on acquisition related loans, which totaled $1.3 million in the second quarter of 2025, $1.1 million in the first quarter of 2025 and $1.6 million in the second quarter of 2024.

The yield on loans on a fully taxable equivalent (FTE) basis for the second quarter of 2025 was 6.26 percent, up 6 basis points from the 6.20 percent for the first quarter of 2025 and down 13 basis points from 6.39 percent in the second quarter of 2024. Cost of deposits for the second quarter of 2025 was 2.36 percent, down 8 basis points from 2.44 percent in the first quarter of 2025 and down 43 basis points from 2.79 percent in the second quarter of 2024. The net interest margin on an FTE basis for the second quarter of 2025 was 3.06 percent, up 11 basis points from 2.95 percent in the first quarter of 2025, and up 37 basis points from 2.69 percent in the second quarter of 2024. This marked the fifth consecutive quarter of net interest margin expansion. The increase in net interest margin on a linked quarter basis was primarily due to fixed-rate asset repricing coupled with decreased deposit costs from lower rates on time deposits and favorable funding mix shift.

Select Yield/Rates

Noninterest Income

Noninterest income for the second quarter of 2025 was $42.4 million, compared to $46.2 million in the first quarter of 2025 and $43.3 million in the second quarter of 2024. The decrease in noninterest income on a linked quarter basis reflected strong performance during the first quarter of 2025, coupled with lower swap fee income due to a large swap transaction and associated fees recorded in the first quarter of 2025, and a Small Business Investment Company (SBIC) valuation adjustment, which are included in other income in the table below.

Noninterest Income

Noninterest Expense

Noninterest expense for the second quarter of 2025 was $138.6 million, compared to $144.6 million in the first quarter of 2025 and $139.4 million in the second quarter of 2024. Included in noninterest expense are certain items consisting of branch right sizing, early retirement program, termination of vendor and software services and an FDIC special assessment. Collectively, these items totaled $1.8 million in the second quarter of 2025, $1.0 million in the first quarter of 2025 and $1.5 million in the second quarter of 2024. Excluding these items (which are described in the “Reconciliation of Non-GAAP Financial Measures” tables below), adjusted noninterest expense1 was $136.8 million for the second quarter of 2025, $143.6 million in the first quarter of 2025 and $137.8 million in the second quarter of 2024. The decrease in adjusted noninterest expense1 on a linked quarter basis reflected lower salaries and benefit expenses primarily due to a seasonal decline in payroll taxes and equity compensation expense, and a decline in other operating expenses resulting from a $4.3 million charge related to a customer deposit fraud event in the first quarter of 2025.

Noninterest Expense

Loans and Unfunded Loan Commitments

Total loans at the end of the second quarter of 2025 were $17.1 billion, up slightly from first quarter 2025 levels. The increase in total loans on a linked quarter basis was broadly-based, driven primarily by growth in the commercial, agricultural, consumer & other portfolios, offset in part by declines in the real estate – commercial and mortgage warehouse portfolios. Unfunded loan commitments at the end of the second quarter of 2025 were $3.9 billion, up $59 million, or 2 percent, from first quarter 2025 levels. The commercial loan pipeline totaled $1.6 billion at the end of the second quarter of 2025, and ready to close commercial loans totaled $564 million with a weighted average rate of 7.35 percent.

Loans and Unfunded Loan Commitments

Deposits and Other Borrowings

Total deposits at the end of the second quarter of 2025 were $21.8 billion, compared to $21.7 billion at the end of the first quarter of 2025 and $21.8 billion at the end of the second quarter of 2024. The increase in total deposits on a linked quarter basis reflected a $233 million increase in low-cost customer deposits (noninterest bearing and interest bearing transaction accounts) and a $324 million increase in brokered deposits, offset in part by a decrease in public fund deposits due to seasonal factors. Other borrowings totaled $1.0 billion at the end of the second quarter of 2025, compared to $1.3 billion at the end of the first quarter of 2025 and $1.8 billion at the end of the second quarter of 2024. The decrease in other borrowings on a linked quarter basis and year-over-year basis was primarily due to a decrease in FHLB advances.

Deposits

Asset Quality

Net charge-offs as a percentage of average loans for the second quarter of 2025 were 25 basis points, compared to 23 basis points in the first quarter of 2025 and 19 basis points in the second quarter of 2024. Net charge-offs in the second quarter of 2025 included $1.1 million of charge-offs associated with the run-off portfolio consisting of small ticket equipment finance and acquired asset-based lending portfolios (run-off portfolio). Net charge-offs from the run-off portfolio accounted for 3 basis points of total net charge-offs in the second quarter of 2025, 4 basis points of total net charge-offs in the first quarter of 2025 and 16 basis points of total net charge-offs in the second quarter of 2024.

Total nonperforming loans at the end of the second quarter of 2025 totaled $157.2 million, compared to $152.4 million at the end of the first quarter of 2025 and $103.4 million at the end of the second quarter of 2024. The increase in nonperforming loans on a year-over-year basis was primarily due to two specific credit relationships that were placed on nonaccrual at the end of first quarter of 2025. The nonperforming loan coverage ratio ended the second quarter of 2025 at 161 percent, compared to 165 percent at the end of the first quarter of 2025 and 223 percent at the end of the second quarter of 2024. Total nonperforming assets as a percentage of total assets were 62 basis points at the end of the second quarter of 2025, compared to 61 basis points at the end of the first quarter of 2025 and 39 basis points at the end of the second quarter of 2024.

Provision for credit losses on loans totaled $11.9 million for the second quarter of 2025, compared to $26.8 million in the first quarter of 2025 and $11.1 million in the second quarter of 2024. The decrease in provision for credit losses on loans on a linked quarter basis was primarily due to $15.6 million of incremental provision related to the aforementioned two specific credit relationships that was recorded in the first quarter of 2025. The allowance for credit losses on loans at the end of the second quarter of 2025 was $253.5 million, compared to $252.2 million at the end of the first quarter of 2025 and $230.4 million at the end of the second quarter of 2024. The allowance for credit losses on loans as a percentage of total loans was 1.48 percent at the end of the second quarter of 2025, unchanged from the first quarter of 2025 and up from 1.34 percent at the end of the second quarter of 2024.

Asset Quality

Capital

Total stockholders’ equity at the end of the second quarter of 2025 was $3.5 billion, up $17.7 million from the end of the first quarter of 2025 and up $90.3 million from the end of the second quarter of 2024. The increase on a year-over-year basis was primarily due to an increase of $53.9 million in retained earnings, coupled with a $24.6 million recapture of accumulated other comprehensive income principally associated with the mark-to-market adjustment on available for sale investment securities. Book value per share at the end of the second quarter of 2025 was $28.17 compared to $28.04 at the end of the first quarter of 2025 and $27.56 at the end of the second quarter of 2024. Tangible book value per share1 at the end of the second quarter of 2025 was $16.97, compared to $16.81 at the end of the first quarter of 2025 and $16.20 at the end of the second quarter of 2024.

Total stockholders’ equity as a percentage of total assets at the end of the second quarter of 2025 was 13.3 percent, compared to 13.2 percent at the end of the first quarter of 2025 and 12.6 percent at the end of the second quarter of 2024. Tangible common equity as a percentage of tangible assets1 at the end of the second quarter of 2025 was 8.5 percent, compared to 8.3 percent at the end of the first quarter of 2025 and 7.8 percent at the end of the second quarter of 2024. Each of the applicable regulatory capital ratios for Simmons and its principal subsidiary, Simmons Bank, continue to significantly exceed “well-capitalized” regulatory guidelines.

Select Capital Ratios

Share Repurchase Program

During the second quarter of 2025, Simmons did not repurchase shares under its stock repurchase program that was authorized in January 2024 (2024 Program), which replaced its former repurchase program that was authorized in January 2022. Remaining authorization under the 2024 Program as of June 30, 2025, was approximately $175 million. The timing, pricing and amount of any repurchases under the 2024 Program will be determined by Simmons’ management at its discretion based on a variety of factors including, but not limited to, market conditions, trading volume and market price of Simmons’ common stock, Simmons’ capital needs, Simmons’ working capital and investment requirements, other corporate considerations, economic conditions, and legal requirements. The 2024 Program does not obligate Simmons to repurchase any common stock and may be modified, discontinued or suspended at any time without prior notice.

Conference Call

Management will conduct a live conference call to review this information beginning at 7:30 a.m. Central Time on Friday, July 18, 2025. Interested persons can listen to this call by dialing toll-free 1-844-481-2779 (North America only) and asking for the Simmons First National Corporation conference call, conference ID 10200827. In addition, the call will be available live or in recorded version on Simmons’ website at simmonsbank.com for at least 60 days following the date of the call.

Simmons First National Corporation

Simmons First National Corporation (NASDAQ: SFNC) is a Mid-South based financial holding company that has paid cash dividends to its shareholders for 116 consecutive years. Its principal subsidiary, Simmons Bank, operates more than 220 branches in Arkansas, Kansas, Missouri, Oklahoma, Tennessee and Texas. Founded in 1903, Simmons Bank offers comprehensive financial solutions delivered with a client-centric approach. In 2024, Simmons Bank was recognized by Newsweek as one of America’s Best Regional Banks 2025, by U.S. News & World Report as one of the 2024-2025 Best Companies to Work For in the South and by Forbes as one of America’s Best-In-State Banks 2024 in Tennessee and America’s Best-In-State Employers 2024 in Missouri. Additional information about Simmons Bank can be found on our website at simmonsbank.com, by following @Simmons_Bank on X (formerly Twitter) or by visiting our newsroom.

Non-GAAP Financial Measures

This press release 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 net income (including on a per share diluted basis), pre-tax, pre-provision earnings, net charge-offs, income available to common shareholders, noninterest income, and noninterest expense certain income and expense items attributable to, for example, merger activity (primarily including merger-related expenses), gains and/or losses on sale of branches, net branch right-sizing initiatives, early retirement program, termination of vendor and software services, FDIC special assessment charges and expenses related to the fraud event reported in the first quarter of 2025.

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 deposits and/or loans acquired through acquisitions, mortgage warehouse loans, and/or energy loans, or gains and/or losses on the sale of securities, or the aforementioned two specific credit relationships. The Company’s management believes that these non-GAAP financial measures 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 and certain other 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 ongoing businesses, and management uses these non-GAAP financial measures to assess the performance of the Company’s ongoing 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 tables of this release.

Forward-Looking Statements

Certain statements in this press release 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, including, without limitation, statements made in Mr. Makris’s quote, may be identified by reference to future periods or by the use of forward-looking terminology, such as “believe,” “budget,” “expect,” “foresee,” “anticipate,” “intend,” “indicate,” “target,” “estimate,” “plan,” “project,” “continue,” “contemplate,” “positions,” “prospects,” “predict,” or “potential,” by future conditional verbs such as “will,” “would,” “should,”

“could,” “might” or “may,” or by variations of such words or by similar expressions. These forward-looking statements include, without limitation, statements relating to Simmons’ future growth, business strategies, lending capacity and lending activity, loan demand, revenue, assets, asset quality, profitability, dividends, net interest margin, non-interest revenue, share repurchase program, acquisition strategy, digital banking initiatives, the Company’s ability to recruit and retain key employees, the adequacy of the allowance for credit losses, future economic conditions and interest rates, and the adequacy of reserve levels for loans. Any forward-looking statement speaks only as of the date of this press release, and Simmons undertakes no obligation to update these forward-looking statements to reflect events or circumstances that occur after the date of this press release. By nature, forward-looking statements are based on various assumptions and involve inherent risk and uncertainties. Various factors, including, but not limited to, changes in economic conditions, changes in credit quality, changes in interest rates and related governmental policies, changes in loan demand, changes in deposit flows, changes in real estate values, changes in the assumptions used in making the forward-looking statements, changes in the securities markets generally or the price of Simmons’ common stock specifically, changes in information technology affecting the financial industry, and changes in customer behaviors, including consumer spending, borrowing, and saving habits; changes in tariff policies; general economic and market conditions; changes in governmental administrations; market disruptions including pandemics or significant health hazards, severe weather conditions, natural disasters, terrorist activities, financial crises, political crises, war and other military conflicts (including the ongoing military conflicts between Russia and Ukraine and between Israel and Iran) or other major events, or the prospect of these events; the soundness of other financial institutions and any indirect exposure related to the closings of other financial institutions and their impact on the broader market through other customers, suppliers and partners, or that the conditions which resulted in the liquidity concerns experienced by closed financial institutions may also adversely impact, directly or indirectly, other financial institutions and market participants with which the Company has commercial or deposit relationships; increased inflation; the loss of key employees; increased competition in the markets in which the Company operates and from non-bank financial institutions; increased unemployment; labor shortages; claims, damages, and fines related to litigation or government actions; changes in accounting principles relating to loan loss recognition (current expected credit losses); fraud that results in material losses or that we have not discovered yet that may result in material losses; the Company’s ability to manage and successfully integrate its mergers and acquisitions and to fully realize cost savings and other benefits associated with acquisitions; increased delinquency and foreclosure rates on commercial real estate loans; significant increases in nonaccrual loan balances; cyber or other information technology threats, attacks or events; reliance on third parties for key services; government legislation; and other factors, many of which are beyond the control of the Company, could cause actual results to differ materially from those projected in or contemplated by the forward-looking statements. In addition, there can be no guarantee that the board of directors (Board) of Simmons will approve a quarterly dividend in future quarters, and the timing, payment, and amount of future dividends (if any) is subject to, among other things, the discretion of the Board and may differ significantly from past dividends. Additional information on factors that might affect the Company’s financial results is included in the Company’s Form 10-K for the year ended December 31, 2024, and other reports that the Company has filed with or furnished to the U.S. Securities and Exchange Commission (the SEC), all of which are available from the SEC on its website, www.sec.gov.

FOR MORE INFORMATION CONTACT:

Ed Bilek, EVP, Director of Investor and Media Relations

ed.bilek@simmonsbank.com or 205.612.3378 (cell)

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