Exhibit 99.1

April 16, 2025

Simmons First National Corporation Reports First Quarter 2025 Results

George Makris, Jr., Simmons’ Chairman and Chief Executive Officer, commented on first quarter 2025 results:

We are pleased with our first quarter’s performance, which demonstrated the continued improvement in profitability fundamentals. Increases in loans and customer deposits combined with a decrease in wholesale funding have driven a healthy increase in our net interest margin and positive trends in total revenue.

We increased the loss provision on two specific credit relationships that we have been watching for some time due to unfavorable events that occurred for both since the end of 2024. Otherwise, we believe the asset quality in our portfolio remains sound. We are, though, carefully monitoring the economic volatility in the United States and the world. Financial markets suffer in times of uncertainty, which appears present today, and can threaten the pace of business investment.

We are hopeful for stability in economic policy, which will provide better insight into future growth opportunities. In the meantime, we will continue to invest in our business as well as the communities we serve.

Simmons First National Corporation (NASDAQ: SFNC) (Simmons or Company) today reported net income of $32.4 million for the first quarter of 2025, compared to $48.3 million in the fourth quarter of 2024 and $38.9 million in the first quarter of 2024. Diluted earnings per share were $0.26 for the first quarter of 2025, compared to $0.38 in the fourth quarter of 2024 and $0.31 in the first quarter of 2024. Adjusted earnings¹ for the first quarter of 2025 were $33.1 million, compared to $49.6 million in the fourth quarter of 2024 and $40.4 million in the first quarter of 2024. Adjusted diluted earnings per share¹ for the first quarter of 2025 were $0.26, compared to $0.39 in the fourth quarter of 2024 and $0.32 in the first quarter of 2024.

The table below summarizes the impact of certain items, consisting primarily of branch right sizing, early retirement and FDIC special assessments. 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 EPS

At the end of the first quarter of 2025, two specific credit relationships totaling $49.8 million migrated to nonperforming. The first credit relationship totaling $26.9 million relates to a downtown St. Louis hotel that was originated pre-pandemic and has been on our classified list since April of 2021. This is the only credit relationship within our portfolio located in downtown St. Louis. While the property securing the relationship remains in operation and we believe is entering a stronger season of the year, the borrower experienced seasonal stress during the first quarter of 2025 combined with harsher than usual winter conditions. As a result, we raised our specific reserve level to 63 percent of principal, which we expect to adequately cover any potential loss beyond the combined value of collateral and recourse.

The second credit relationship totaling $22.9 million relating to a fast-food operator primarily resulted from our latest acquisition and has been on our classified list since June of 2024 due to sector-related headwinds and global cash flow concerns with the borrower. While such loan was current on interest as of March 31, 2025, the migration to nonperforming was due, in part, to the fact that we identified a large customer deposit fraud during the first quarter of 2025 that concerned entities affiliated with the borrower (the “Fraud Event”). (Accordingly, total noninterest expense during the first quarter of 2025 included a charge of $4.3 million associated with the Fraud Event.) The specific reserve on this relationship was raised to 61 percent of principal, which we expect to adequately cover any potential loss beyond the combined value of collateral and recourse. In total, the incremental provision expense associated with these two specific credit relationships accounted for $15.6 million of the total $26.8 million of provision for credit losses on loans recorded during the first quarter of 2025.

Net Interest Income

Net interest income for the first quarter of 2025 totaled $163.4 million, compared to $164.9 million in the fourth quarter of 2024 and $151.9 million in the first quarter of 2024. Interest income totaled $307.8 million for the first quarter of 2025, compared to $326.0 million in the fourth quarter of 2024 and $322.6 million in the first quarter of 2024. The decrease in interest income on a linked quarter basis was primarily driven by interest rate cuts at the end

of 2024 and the corresponding decline in earning asset yields, lower day count in the comparable quarters and a reduction in swap income given the reduction in interest rates. Interest expense totaled $144.4 million for the first quarter of 2025, compared to $161.0 million in the fourth quarter of 2024 and $170.7 million in the first quarter of 2024. The decrease in interest expense reflected a lower interest rate environment, management’s efforts to proactively manage deposit costs and a reduction in the use of wholesale funding. Included in net interest income is accretion recognized on acquisition related loans, which totaled $1.1 million in the first quarter of 2025, $1.9 million in the fourth quarter of 2024 and $1.1 million in the first quarter of 2024.

The yield on loans on a fully taxable equivalent (FTE) basis for the first quarter of 2025 was 6.20 percent, down 12 basis points from 6.32 percent for the fourth quarter of 2024 and down 4 basis points from 6.24 percent in the first quarter of 2024. Cost of deposits for the first quarter of 2025 was 2.44 percent, down 16 basis points from 2.60 percent in the fourth quarter of 2024 and 31 basis points from 2.75 percent in the first quarter of 2024. The net interest margin on an FTE basis for the first quarter of 2025 was 2.95 percent, up 8 basis points from 2.87 percent in the third quarter of 2024 and up 29 basis points from 2.66 percent in the first quarter of 2024. This marked the fourth consecutive quarter of net interest margin expansion. The increase in net interest margin on a linked quarter basis was primarily due to lower deposits costs, as well as the reduced rate and use of wholesale funding that more than offset a decline on the yield and volume of earning assets.

Select Yield/Rates

Noninterest Income

Noninterest income for the first quarter of 2025 was $46.2 million, compared to $43.6 million in the fourth quarter of 2024 and $43.2 million in the first quarter of 2024. The increase in noninterest income on a linked quarter basis was primarily due to increased swap fee income and fair value adjustments on Small Business Investment Company (SBIC) investments, which are included in “Other income” in the table below. The increase in noninterest income on a year-over-year basis was primarily due to increased swap fee income, coupled with increases in wealth management fees and service charges on deposit accounts.

Noninterest Income

Noninterest Expense

Noninterest expense for the first quarter of 2025 was $144.6 million, compared to $141.1 million in the fourth quarter of 2024 and $139.9 million in the first quarter of 2024. Included in noninterest expense are certain items consisting of branch right sizing, early retirement and an FDIC special assessment. Collectively, these items totaled $1.0 million in the first quarter of 2025, $1.8 million in the fourth quarter of 2024 and $2.0 million in the first quarter of 2024. Excluding these items (which are described in the “Reconciliation of Non-GAAP Financial Measures” tables below), adjusted noninterest expense¹ was $143.6 million for the first quarter of 2025, $139.3 million in the fourth quarter of 2024 and $137.9 million in the first quarter of 2024. The increase in adjusted noninterest expense on a linked quarter basis reflected increased salaries and benefits primarily due to seasonally higher payroll taxes and the previously mentioned Fraud Event. Excluding the $4.3 million of expenses associated with the Fraud Event, adjusted noninterest expense for the first quarter of 2025 would have been $139.3 million ¹, down slightly from fourth quarter 2024 levels.

Noninterest Expense

Loans and Unfunded Loan Commitments

Total loans at the end of the first quarter of 2025 were $17.1 billion, compared to $17.0 billion at the end of both the fourth quarter of 2024 and the first quarter of 2024. The increase in total loans on a linked quarter basis was primarily due to growth in the commercial real estate, mortgage warehouse and agricultural portfolios. Unfunded loan commitments at the end of the first quarter of 2025 were $3.9 billion, up $149 million, or 4 percent, from fourth quarter 2024 levels. The commercial loan pipeline totaled $1.8 billion at the end of the first quarter of 2025, up 43 percent compared to the fourth quarter of 2024, and ready to close commercial loans totaled $757 million, marking the third consecutive quarterly increase in both metrics.

Loans and Unfunded Loan Commitments

Deposits and Other Borrowings

Total deposits at the end of the first quarter of 2025 were $21.7 billion, compared to $21.9 billion at the end of the fourth quarter of 2024 and $22.4 billion at the end of the first quarter of 2024. The decrease in total deposits on a linked quarter basis was primarily due to a decline in time deposits and brokered deposits, offset in part by an increase in interest bearing transaction accounts (checking, money market and savings accounts, and public funds). Other borrowings totaled $1.3 billion at the end of the first quarter of 2025, compared to $1.1 billion at the end of the fourth quarter of 2024. The increase in other borrowings on a linked quarter was primarily due to an increase in FHLB advances.

Deposits

Asset Quality

Net charge-offs as a percentage of average loans for the first quarter of 2025 were 23 basis points, compared to 27 basis points in the fourth quarter of 2024 and 19 basis points in the first quarter of 2024. Net charge-offs in the first quarter of 2025 included $1.9 million of charge-offs associated with a 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 4 basis points of total net charge-offs during the first quarter of 2025, 6 basis points of total net charge-offs during the fourth quarter of 2024 and 11 basis points of total net charge-offs in the first quarter of 2024.

Total nonperforming loans at the end of the first quarter of 2025 totaled $152.3 million, compared to $110.7 million at the end of the fourth quarter of 2024 and $107.3 million at the end of the first quarter of 2024. The increase in the nonperforming loans on a linked quarter basis and year-over-year basis was primarily due to the two specific credit relationships discussed above that were placed on nonaccrual at the end of the first quarter of 2025. The nonperforming loan coverage ratio ended the first quarter of 2025 at 165 percent, compared to 212 percent at both the end of the fourth quarter of 2024 and the first quarter of 2024. Total nonperforming assets as a percentage of total assets were 61 basis points at the end of the first quarter of 2025, compared to 45 basis points at the end of the fourth quarter of 2024 and 41 basis points at the end of the first quarter of 2024.

Provision for credit losses on loans totaled $26.8 million for the first quarter of 2025, compared to $13.3 million in the fourth quarter of 2024 and $10.2 million in the first quarter of 2024. The increase in provision for credit losses on loans primarily reflected $15.6 million of incremental provision related to the aforementioned two specific credit relationships. The allowance for credit losses on loans at the end of the first quarter of 2025 was $252.2 million, compared to $235.0 million at the end of the fourth quarter of 2024 and $227.4 million at the end of the first 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 first quarter of 2025, compared to 1.38 percent at the end of the fourth quarter of 2024 and 1.34 percent at the end of the first quarter of 2024.

Asset Quality

Capital

Total stockholders’ equity at the end of the first quarter of 2025 was $3.5 billion, up slightly from the end of the fourth quarter of 2024 and up $92.4 million from $3.4 billion at the end of the first quarter of 2024. The increase on a year-over-year basis was primarily due to an increase of $40.3 million in retained earnings, coupled with a $40.3 million recapture of accumulated other comprehensive income principally associated with the mark-to-market adjustment on AFS investment securities. Book value per share at the end of the first quarter of 2025 was $28.04, compared to $28.08 at the end of the fourth quarter of 2024 and $27.42 at the end of the first quarter of 2024. Tangible book value per share¹ at the end of the first quarter of 2025 was $16.81, compared to $16.80 at the end of the fourth quarter of 2024 and $16.02 at the end of the first quarter of 2024.

Total stockholders’ equity as a percentage of total assets at the end of the first quarter of 2025 was 13.2 percent, compared to 13.1 percent at the end of the fourth quarter of 2024 and 12.6 percent at the end of the first quarter of 2024. Tangible common equity as a percentage of tangible assets¹ at the end of the first quarter of 2025 was 8.3 percent, up slightly from fourth quarter 2024 levels and up from 7.8 percent reported at the end of the first 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 first 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 March 31, 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 Thursday, April 17, 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 10198144. 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 222 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 Banks 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, FDIC special assessment charges and expenses related to the Fraud Event.

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) 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)

Page 1

Page 2

Page 3

Page 4