Stellar Bancorp, Inc. (STEL)

ITEM 2. MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS

Except where the context otherwise requires or where otherwise indicated in this Quarterly Report on Form 10-Q, the term “Stellar” refers to Stellar Bancorp, Inc., the terms “we,” “us,” “our,” “Company” and “our business” refer to Stellar Bancorp, Inc. and our wholly owned banking subsidiary, Stellar Bank, a Texas banking association.

Cautionary Notice Regarding Forward-Looking Statements

This Quarterly Report on Form 10-Q contains forward‑looking statements. These forward‑looking statements reflect the Company’s current views with respect to, among other things, future events and the Company’s financial performance. These statements are often, but not always, made through the use of words or phrases such as “may,” “should,” “could,” “predict,” “potential,” “believe,” “will likely result,” “expect,” “continue,” “will,” “anticipate,” “seek,” “estimate,” “intend,” “plan,” “projection,” “would” and “outlook,” or the negative version of those words or other comparable words or phrases of a future or forward‑looking nature. These forward‑looking statements are not historical facts, and are based on current expectations, estimates and projections about the Company’s industry, management’s beliefs and certain assumptions made by management, many of which, by their nature, are inherently uncertain and beyond the Company’s control. Accordingly, the Company cautions that any such forward‑looking statements are not guarantees of future performance and are subject to risks, assumptions and uncertainties that are difficult to predict. Although the Company believes that the expectations reflected in these forward‑looking statements are reasonable as of the date made, actual results may prove to be materially different from the results expressed or implied by the forward‑looking statements.

There are or will be important factors that could cause the Company’s actual results to differ materially from those indicated in these forward‑looking statements, including, but not limited to, the risks described in “Part I— Item 1A.—Risk Factors” in the Company’s Annual Report on Form 10-K for the year ended December 31, 2025 and the following:

•the proposed transaction with Prosperity, including the likelihood of the satisfaction of the conditions to the completion of the transaction and whether and when the transaction will be consummated;

•disruptions to the economy and the U.S. banking system caused by recent bank failures;

•risks associated with uninsured deposits and responsive measures by federal or state governments or banking regulators, including increases in our deposit insurance assessments and other actions of the Board of Governors of the Federal Reserve System, FDIC and Texas Department of Banking, legislative and regulatory actions and reforms and executive orders;

•the effects of and changes in trade and monetary and fiscal policies and laws, including the interest rate policies of the Federal Reserve Board and the imposition of tariffs and retaliatory tariffs;

•inflation, interest rate, capital and securities markets and monetary fluctuations;

•changes in the interest rate environment, the value of the Company’s assets and obligations and the availability of capital and liquidity;

•general competitive, economic, political and market conditions and other factors that may affect future results of the Company including changes in asset quality and credit risk;

•local, regional, national and international economic conditions and the impact they may have on the Company and our customers and the Company’s assessment of that impact;

•the inability to sustain revenue and earnings growth;

•impairment of the Company’s goodwill or other intangible assets;

•the composition of the Company’s loan portfolio and the concentration of loans in commercial real estate and commercial real estate construction;

•the geographic concentration of the Company’s market;

•the accuracy and sufficiency of the assumptions and estimates the Company makes in establishing reserves for potential loan losses and other estimates;

•the amount of nonperforming and classified assets that the Company holds and the time and effort necessary to resolve nonperforming assets;

•deterioration of asset quality;

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•customer borrowing, repayment, investment and deposit practices;

•the ability to maintain important deposit customer relationships;

•changes in the value of collateral securing the Company’s loans;

•natural disasters, climate change and adverse weather in the Company’s market area;

•the impact of pandemics, epidemics or any other health-related crisis;

•acts of terrorism, an outbreak of hostilities, such as the conflicts in Ukraine or the Middle East, or other international or domestic calamities;

•the ability to maintain effective internal control over financial reporting;

•the cost and effects of cyber incidents or other failures, interruptions or security breaches of the Company’s systems or those of the Company’s customers or third-party providers;

•the failure of certain third or fourth-party vendors to perform;

•the impact, extent and timing of technological changes;

•the institution and outcome of litigation and other legal proceedings against the Company or to which it may become subject;

•the costs, effects and results of regulatory examinations, investigations, or reviews or the ability to obtain required regulatory approvals or meet conditions associated with the same;

•changes in the laws, rules, regulations, interpretations or policies relating to financial institution, accounting, tax, trade, monetary and fiscal matters;

•the effect of changes in accounting policies and practices, as may be adopted by the regulatory agencies, as well as the Public Company Accounting Oversight Board, the Financial Accounting Standards Board and other accounting standard setters; and

•other risks, uncertainties, and factors that are discussed from time to time in the Company’s reports and documents filed with the SEC.

The foregoing factors should not be construed as exhaustive and should be read together with the other cautionary statements included in this Quarterly Report on Form 10-Q. This discussion and analysis includes forward-looking statements that are subject to certain risks and uncertainties and are based on certain assumptions that the Company believes are reasonable but may prove to be inaccurate. Certain risks, uncertainties and other factors, including those set forth above may cause actual results to differ materially from projected results discussed in the forward-looking statements appearing in this discussion and analysis.

The Company disclaims any obligation and does not intend to update or revise any forward-looking statements contained in this Quarterly Report on Form 10-Q, which speak only as of the date hereof, whether as a result of new information, future events or otherwise, except as required by federal securities laws. As forward-looking statements involve significant risks and uncertainties, caution should be exercised against placing undue reliance on such statements.

Pending Merger with Prosperity

On January 27, 2026, the Company entered into the Agreement and Plan of Merger (the “Merger Agreement”) with Prosperity Bancshares, Inc., a Texas corporation (“Prosperity”). The Merger Agreement provides that, upon the terms and subject to the conditions set forth therein, the Company will merge with and into Prosperity (the “Merger”), with Prosperity continuing as the surviving corporation in the Merger. Immediately following the Merger, Stellar Bank will merge with and into Prosperity’s wholly owned banking subsidiary, Prosperity Bank (the “Bank Merger”). Prosperity Bank will continue as the surviving bank in the Bank Merger. Upon the terms and subject to the conditions set forth in the Merger Agreement, at the effective time of the Merger (the “Effective Time”), each share of common stock, par value $0.01 per share, of the Company (“Stellar Common Stock”) outstanding immediately prior to the Effective Time, other than certain shares held by Prosperity or Stellar and shares held by a holder of Stellar Common Stock who has properly exercised applicable dissenters’ rights in respect of such share, will be converted into the right to receive (i) 0.3803 shares of common stock, par value $1.00 per share, of Prosperity and (ii) an amount in cash equal to $11.36. Stellar and Prosperity have received all regulatory approvals necessary to complete the Merger and the Bank Merger. In connection with the Merger, Stellar has called a special meeting of its shareholders to be held on May 27, 2026. Stellar shareholders of record as of the close of business on April 10, 2026 are entitled to vote at the special meeting. Completion of the Merger and the Bank Merger remains subject to Stellar shareholder approval and satisfaction of remaining customary closing conditions. The Merger is expected to be completed on or about July 1, 2026, subject to approval by Stellar shareholders and the satisfaction or waiver of other customary closing conditions set forth in the Merger Agreement. See Part I, Item 1A, “Risk Factors,” and Part II, Item 7, “Management’s Discussion and Analysis of Financial Condition and Results of Operations” included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2025.

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Overview

We generate a majority of our income from interest income on loans, interest income from investments in securities and service charges on customer accounts. We incur interest expense on deposits and other borrowed funds and noninterest expenses such as salaries and employee benefits and occupancy expenses. Net interest income is the difference between interest income on earning assets such as loans and securities and interest expense on liabilities such as deposits and borrowings that are used to fund those assets. Net interest income is our largest source of revenue. To evaluate net interest income, we measure and monitor (1) yields on our loans and other interest-earning assets, (2) the interest expenses of our deposits and other funding sources, (3) our net interest spread and (4) our net interest margin. Net interest spread is the difference between rates earned on interest-earning assets and rates paid on interest-bearing liabilities. Net interest margin is calculated as net interest income divided by average interest-earning assets. Because noninterest-bearing sources of funds, such as noninterest-bearing deposits and shareholders’ equity, also fund interest-earning assets, net interest margin includes the benefit of these noninterest-bearing sources.

Our net interest income is affected by changes in the amount and mix of interest-earning assets and interest-bearing liabilities, referred to as a “volume change.” Periodic changes in the volume and types of loans in our loan portfolio are affected by, among other factors, economic and competitive conditions in Texas and specifically in our market, as well as developments affecting the real estate, technology, financial services, insurance, transportation, manufacturing and energy sectors within our market and throughout the state of Texas.

Our net interest income is also affected by changes in yields earned on interest-earning assets and rates paid on interest-bearing deposits and borrowed funds, referred to as a “rate change.” Fluctuations in market interest rates are driven by many factors, including governmental monetary policies, inflation, deflation, macroeconomic developments, changes in unemployment, the money supply, political and international conditions and conditions in domestic and foreign financial markets.

Critical Accounting Policies

Certain of our accounting estimates are important to the portrayal of our financial condition, since they require ma

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ITEM 7. MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS

Cautionary Notice Regarding Forward-Looking Statements

This Annual Report on Form 10-K contains forward‑looking statements. These forward‑looking statements reflect the Company’s current views with respect to, among other things, future events and the Company’s financial performance. These statements are often, but not always, made through the use of words or phrases such as “may,” “should,” “could,” “predict,” “potential,” “believe,” “will likely result,” “expect,” “continue,” “will,” “anticipate,” “seek,” “estimate,” “intend,” “plan,” “projection,” “would,” and “outlook,” or the negative version of those words or other comparable words or phrases of a future or forward‑looking nature. These forward‑looking statements are not historical facts, and are based on current expectations, estimates and projections about the Company’s industry, management’s beliefs and certain assumptions made by management, many of which, by their nature, are inherently uncertain and beyond the Company’s control. Accordingly, the Company cautions that any such forward‑looking statements are not guarantees of future performance and are subject to risks, assumptions and uncertainties that are difficult to predict. Although the Company believes that the expectations reflected in these forward‑looking statements are reasonable as of the date made, actual results may prove to be materially different from the results expressed or implied by the forward‑looking statements.

There are or will be important factors that could cause the Company’s actual results to differ materially from those indicated in these forward‑looking statements, including, but not limited to, the risks described in “Part I.—Item 1A.—Risk Factors” and the following:

•the proposed transaction with Prosperity, including the likelihood of the satisfaction of the conditions to the completion of the transaction and whether and when the transaction will be consummated;

•disruptions to the economy and the U.S. banking system caused by recent bank failures;

•risks associated with uninsured deposits and responsive measures by federal or state governments or banking regulators, including increases in our deposit insurance assessments and other actions of the Board of Governors of the Federal Reserve System, FDIC and Texas Department of Banking, legislative and regulatory actions and reforms and executive orders;

•the effects of and changes in trade and monetary and fiscal policies and laws, including the interest rate policies of the Federal Reserve Board and the imposition of tariffs and retaliatory tariffs;

•inflation, interest rate, capital and securities markets and monetary fluctuations;

•changes in the interest rate environment, the value of the Company’s assets and obligations and the availability of capital and liquidity;

•general competitive, economic, political and market conditions and other factors that may affect future results of the Company including changes in asset quality and credit risk;

•local, regional, national and international economic conditions and the impact they may have on the Company and our customers and the Company’s assessment of that impact;

•the inability to sustain revenue and earnings growth;

•impairment of the Company’s goodwill or other intangible assets;

•the composition of the Company’s loan portfolio and the concentration of loans in commercial real estate and commercial real estate construction;

•the geographic concentration of the Company’s market;

•the accuracy and sufficiency of the assumptions and estimates the Company makes in establishing reserves for potential loan losses and other estimates;

•the amount of nonperforming and classified assets that the Company holds and the time and effort necessary to resolve nonperforming assets;

•deterioration of asset quality;

•customer borrowing, repayment, investment and deposit practices;

•the ability to maintain important deposit customer relationships;

•changes in the value of collateral securing the Company’s loans;

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•natural disasters, climate change and adverse weather in the Company’s market area;

•the impact of pandemics, epidemics or any other health-related crisis;

•acts of terrorism, an outbreak of hostilities, such as the conflicts in Ukraine or the Middle East, or other international or domestic calamities;

•the ability to maintain effective internal control over financial reporting;

•the cost and effects of cyber incidents or other failures, interruptions or security breaches of the Company's systems or those of the Company’s customers or third-party providers;

•the failure of certain third- or fourth-party vendors to perform;

•the impact, extent and timing of technological changes;

•the institution and outcome of litigation and other legal proceedings against the Company or to which it may become subject;

•the costs, effects and results of regulatory examinations, investigations, or reviews or the ability to obtain required regulatory approvals or meet conditions associated with the same;

•changes in the laws, rules, regulations, interpretations or policies relating to financial institution, accounting, tax, trade, monetary and fiscal matters;

•the effect of changes in accounting policies and practices, as may be adopted by the regulatory agencies, as well as the Public Company Accounting Oversight Board, the Financial Accounting Standards Board and other accounting standard setters; and

•other risks, uncertainties, and factors that are discussed from time to time in the Company’s reports and documents filed with the SEC.

The following discussion and analysis of the Company’s financial condition and results of operations should be read in conjunction with “Item 15. Exhibits and Financial Statement Schedules” and the consolidated financial statements and the accompanying notes included elsewhere in this Annual Report on Form 10-K. This discussion and analysis includes forward-looking statements that are subject to certain risks and uncertainties and are based on certain assumptions that the Company believes are reasonable but may prove to be inaccurate. Certain risks, uncertainties and other factors, including those set forth in “Part I. Item 1A.—Risk Factors” and elsewhere in this Annual Report on Form 10-K, may cause actual results to differ materially from those projected results discussed in the forward-looking statements appearing in this discussion and analysis.

The Company disclaims any obligation and does not intend to update or revise any forward-looking statements contained in this Annual Report on Form 10-K, which speak only as of the date hereof, whether as a result of new information, future events or otherwise, except as required by federal securities laws. As forward-looking statements involve significant risks and uncertainties, caution should be exercised against placing undue reliance on such statements.

Overview

We generate most of our income from interest income on loans, interest income from investments in securities and service charges on customer accounts. We incur interest expense on deposits and other borrowed funds and noninterest expenses such as salaries and employee benefits and occupancy expenses. Net interest income is the difference between interest income on earning assets such as loans and securities and interest expense on liabilities such as deposits and borrowings that are used to fund those assets. Net interest income is our largest source of revenue. To evaluate net interest income, we measure and monitor (1) yields on our loans and other interest-earning assets, (2) the interest expenses of our deposits and other funding sources, (3) our net interest spread and (4) our net interest margin. Net interest spread is the difference between rates earned on interest-earning assets and rates paid on interest-bearing liabilities. Net interest margin is calculated as net interest income divided by average interest-earning assets. Because noninterest-bearing sources of funds, such as noninterest-bearing deposits and shareholders’ equity, also fund interest-earning assets, net interest margin includes the benefit of these noninterest-bearing sources.

Our net interest income is affected by changes in the amount and mix of interest-earning assets and interest-bearing liabilities, referred to as a “volume change.” Periodic changes in the volume and types of loans in our loan portfolio are affected by, among other factors, economic and competitive conditions in Texas and specifically in our market, as well as developments affecting the real estate, technology, financial services, insurance, transportation, manufacturing and energy sectors within our market and throughout the state of Texas.

Our net interest income is also affected by changes in yields earned on interest-earning assets and rates paid on interest-bearing deposits and borrowed funds, referred to as a “rate change.” Fluctuations in market interest rates are driven by many factors,

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including governmental monetary policies, inflation, deflation, macroeconomic developments, changes in unemployment, the money supply, political and international conditions and conditions in domestic and foreign financial markets.

On January 27, 2026, the Company entered into the Agreement and Plan of Merger (the “Merger Agreement”) with Prosperity Bancshares, Inc., a Texas corporation (“Prosperity”). The Merger Agreement provides that, upon the terms and subject to the conditions set forth therein, the Company will merge with and into Prosperity (the “Merger”), with Prosperity continuing as the surviving corporation in the Merger. Immediately following the Merger, Stellar Bank will merge with and into Prosperity’s wholly owned banking subsidiary, Prosperity Bank (the “Bank Merger”). Prosperity Bank will continue as the surviving bank in the Bank Merger. Upon the terms and subject to the conditions set forth in the Merger Agreement, at the effective time of the Merger (the “Effective Time”), each share of common stock, par value $0.01 per share, of the Company (“Stellar Common Stock”) outstanding immediately prior to the Effective Time, other than certain shares held by Prosperity or Stellar and shares held by a holder of Stellar Common Stock who has properly exercised applicable dissenters’ rights in respect of such share, will be converted into the right to receive (i) 0.3803 shares of common stock, par value $1.00 per share, of Prosperity and (ii) an amount in cash equal to $11.36. The closing of the Merger is expected to occur in the second quarter of 2026, subject to customary conditions, including approval of the Company's shareholders and regulatory approvals. See Part I, Item 1A, “Risk Factors,” Part II, Item 7, “Management’s Discussion and Analysis of Financial Condition and Results of Operations,” and Note 18 – Subsequent Events of the Notes to Consolidated Financial Statement included in this Annual Report on Form 10-K for additional information regarding the transaction.

Critical Accounting Policies

Certain of our accounting estimates are important to the portrayal of our financial condition, since they require management to make difficult, complex or subjective judgments, some of which may relate to matters that are inherently uncertain. Estimates are susceptible to material changes as a result of changes in facts and circumstances. Facts and circumstances that could affect these judgments include, but are not limited to, changes in interest rates, changes in the performance of the economy and changes in the financial condition of borrowers. Management believes that determining the allowance for credit losses is its most critical accounting estimate. Our accounting policies are discussed in detail in Note 1 – Nature of Operations and Summary of Significant Accounting and Reporting Policies in the accompanying notes to the consolidated financial statements.

Allowance for Credit Losses

The allowance for credit losses is a valuation account which represents management’s best estimate of lifetime expected losses based on reasonable and supportable forecasts, historical loss experience, and other qualitative considerations. Management considers the policies related to the allowance for credit losses as the most critical to the financial statement presentation. The Company bases its estimates of credit losses on three primary components: (1) estimates of expected losses that exist in various segments of performing loans over the remaining life of the loan portfolio using a reasonable and supportable economic forecast, (2) specifically identified losses in individually analyzed credits which are collateral-dependent, which generally include nonaccrual loans and purchased credit deteriorated (“PCD”) loans and (3) qualitative factors related to economic conditions, portfolio concentrations, regulatory policy updates, and other relevant factors that address estimates of expected losses. Estimating the timing and amounts of future losses is subject to management’s judgment as these projected cash flows rely upon the estimates discussed above and factors that are reflective of current or future expected conditions using analytical and forecasting models and tools. Volatility in certain credit metrics and differences between expected and actual outcomes are to be expected. For example, customers may not repay their loans according to the original terms, and the collateral securing the payment of those loans may be insufficient to pay any remaining loan balance.

Loans with similar risk characteristics are aggregated into homogenous pools and are collectively evaluated by applying reserve factors, such as historical lifetime loss, concentration risk, volume, growth and composition of the loan portfolio, current and forecasted economic conditions to amortized cost balances over the remaining contractual life of the collectively evaluated portfolio. Historical lifetime loss is determined by utilizing an open-pool cumulative loss rate methodology, adjusted for credit risk characteristics and current and forecasted economic conditions. Losses are predicted over a reasonable and supportable period of one year for all loan pools, followed by an immediate reversion to long-term historical averages. The reasonable and supportable period and reversion period are re-evaluated as needed by the Company and are dependent on the current economic environment among other factors.

Loans that no longer share risk characteristics with the collectively evaluated loan pools are evaluated on an individual basis and are excluded from the collectively evaluated pools. In order to assess which loans are to be individually evaluated, the Company follows a loan review program to evaluate the credit risk in the total loan portfolio and assigns risk grades to each loan. Individual credit loss estimates are typically performed for nonaccrual loans and all other loans identified by management. All loans deemed as being individually evaluated are reviewed on a quarterly basis in order to determine whether a specific reserve is required. The

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Company considers certain loans to be collateral dependent if the borrower is experiencing financial difficulty and management expects repayment for the loan to be substantially through the operation or sale of the collateral. For collateral dependent loans, loss estimates are based on the fair value of collateral, less estimated cost to sell (if applicable). Collateral values supporting individually evaluated loans are assessed quarterly and appraisals are typically obtained at least annually. The Company allocates a specific loan loss reserve on an individual loan basis primarily based on the value of the collateral securing the individually evaluated loan. Through this loan review process, the Company assesses the overall quality of the loan portfolio and the adequacy of the allowance for credit losses on loans while considering risk elements attributable to particular loan types in assessing the quality of individual loans. In addition, for each category of loans, the Company considers secondary sources of income and the financial strength and credit history of the borrower and any guarantors.

A change in the allowance for credit losses on loans can be attributable to several factors, most notably historical lifetime loss, specific reserves for individually evaluated loans, changes in qualitative factors and growth within the loan portfolio. The estimated loan losses for all loan pools are adjusted for changes in qualitative factors not inherently considered in the quantitative analyses to bring the allowance to the level management believes is appropriate based on factors that have not otherwise been fully accounted for, including adjustments for foresight risk, input imprecision and model imprecision. The qualitative categories and the measurements used to quantify the risks within each of these categories are subjectively selected by management, but measured by objective measurements period over period. The data for each measurement may be obtained from internal or external sources. The current period measurements are evaluated and assigned a factor commensurate with the current level of risk relative to past measurements over time. The resulting qualitative adjustments are applied to the relevant collectively evaluated loan portfolios. These adjustments are based upon quarterly trend assessments in portfolio concentrations, changes in lending policies and procedures, policy exceptions, independent loan review results, internal risk ratings and peer group credit quality trends. Additional qualitative considerations are made for any identified risk which did not exist within our portfolio historically and therefore may not be adequately addressed through evaluation of such risk factors based on historical portfolio trends. Qualitative adjustments also include current and forecasted economic conditions primarily measured by local and national economic metrics, such as GDP, unemployment rates, interest rates and oil and gas prices based on historical and forecasted economic research scenarios provided by industry-leading financial intelligence and analytical solutions, which the Company has subscribed to. The qualitative allowance allocation is increased or decreased for each loan pool based on the assessment of these various qualitative factors. Management recognizes the sensitivity of various assumptions made in the quantitative modeling of expected losses and may adjust reserves depending upon the level of uncertainty that currently exists in one or more assumptions.

As of December 31, 2025, based on sensitivity analyses across all segments of the performing loan portfolio, a 5% increase in historical loss rates would have increased funded reserves by $1.1 million. On the other hand, a 5% increase in each qualitative risk factor across all segments (where assigned) would have increased funded reserves by $2.9 million. Increasing estimated loss rates by 5% (i.e. quantitative and qualitative) would have a $3.5 million impact.

The allowance for credit losses could be affected by significant downturns in circumstances relating to loan quality and economic conditions and as such may not be sufficient to cover expected losses in the loan portfolio which could necessitate additional provisions or a reduction in the allowance for credit losses if our assumption prove to be incorrect. Unanticipated changes and events could have a significant impact on the financial performance of borrowers and their ability to perform as agreed. We may experience significant credit losses if borrowers experience financial difficulties, which could have a material adverse effect on our operating results.

Goodwill

Goodwill represents the excess of the consideration paid over the fair value of the net assets acquired in a business combination. During the measurement period, the Company may record subsequent adjustments to goodwill for provisional amounts recorded at the acquisition date.

Goodwill is subject to impairment testing, which must be conducted at least annually or upon the occurrence of a triggering event. Goodwill is recorded and evaluated for impairment at its reporting unit, the Company. The Company’s policy is to test goodwill for impairment at least annually as of October 1st, or on an interim basis if an event triggering an impairment assessment is determined to have occurred. Various factors, such as the Company’s results of operations, the trading price of the Company’s common stock relative to the book value per share, macroeconomic conditions and conditions in the banking sector, inform whether a triggering event for an interim goodwill impairment test has occurred. The impairment test compares the estimated fair value of each reporting unit with its net book value. If the unit’s fair value is less than its carrying value, an impairment loss is recognized in our results of operations in the periods in which they become known in an amount equal to this excess.

See Note 2 – Goodwill and Other Intangible Assets to the consolidated financial statements for additional information on the Company’s goodwill balances.

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Recently Issued Accounting Pronouncements

We have evaluated new accounting pronouncements that have recently been issued. Refer to Note 1 – Nature of Operations and Summary of Significant Accounting and Reporting Policies in the accompanying notes to the consolidated financial statements for a discussion of recent accounting pronouncements that have been adopted by the Company or that will require enhanced disclosures in the Company’s financial statements in future periods.

Pending Merger with Prosperity

On January 27, 2026, we entered into the Merger Agreement with Prosperity. Upon the terms and subject to the conditions set forth therein, the Company will merge with and into Prosperity with Prosperity continuing as the surviving corporation in the Merger. Immediately following the Merger, Stellar Bank will merge with and into Prosperity’s wholly owned banking subsidiary, Prosperity Bank. Prosperity Bank will continue as the surviving bank in the Bank Merger.

At the Effective Time of the Merger, each share of the Company’s common stock outstanding immediately prior to the Effective Time (other than certain shares held by Prosperity or the Company and shares held by a holder of the Company’s common stock who has properly exercised applicable dissenters’ rights in respect of such share) will be converted into the right to receive (1) 0.3803 shares of common stock, par value $1.00 per share, of Prosperity (the “Exchange Ratio”), and (2) an amount in cash equal to $11.36 (the “Per Share Cash Merger Consideration”).

The Merger Agreement contains customary representations and warranties from both Prosperity and the Company, and each party has agreed to customary covenants, including, among others, covenants relating to (1) the conduct of its business or the taking of certain extraordinary actions during the interim period between the execution of the Merger Agreement and the Effective Time and (2) the Company’s obligation to call a meeting of its shareholders to approve the Merger and the Merger Agreement, and, subject to certain exceptions, to recommend that its shareholders approve the Merger and the Merger Agreement. The Company has also agreed to certain non-solicitation obligations related to alternative business combination proposals.

The completion of the Merger is subject to customary conditions, including (1) approval of the Merger Agreement by the Company’s shareholders, (2) authorization for listing on the New York Stock Exchange of the shares of Prosperity Common Stock to be issued in the Merger, subject to official notice of issuance, (3) the receipt of required regulatory approvals, including the approval or waiver of prior approval of the Board of Governors of the Federal Reserve System, the Federal Deposit Insurance Corporation and the Texas Department of Banking, (4) effectiveness of the registration statement on Form S-4 for the Prosperity Common Stock to be issued in the Merger, and (5) the absence of any order, injunction, decree or other legal restraint preventing the completion of the Merger, the Bank Merger or any of the other transactions contemplated by the Merger Agreement or making the completion of the Merger, the Bank Merger or any of the other transactions contemplated by the Merger Agreement illegal. Each party’s obligation to complete the Merger is also subject to certain additional customary conditions, including (1) subject to certain exceptions, the accuracy of the representations and warranties of the other party, (2) performance in all material respects by the other party of its obligations under the Merger Agreement and (3) receipt by such party of an opinion from counsel to the effect that the Merger will qualify as a reorganization within the meaning of Section 368(a) of the Internal Revenue Code of 1986, as amended.

The Merger Agreement contained certain termination rights for the Company and Prosperity. Subject to the terms and conditions of the Merger Agreement, the Company or Prosperity may terminate the Merger Agreement if the Merger is not consummated on or before January 27, 2027, which period may be extended automatically if at the end of the initial period, either of the conditions relating to the approval of the Merger pursuant to various regulatory requirements or the absence of certain legal restraints preventing or otherwise making illegal the consummation of the Merger has not been satisfied. Upon termination of the Merger Agreement, under specified circumstances, the Company will be required to pay Prosperity a termination fee of $78 million.

At the Effective Time, each Company stock option with a per-share exercise price that is less than the Per Share Merger Consideration Value will be cancelled and the holder of such cancelled option will be entitled to receive (without interest) an amount in cash equal to the product of (1) the excess of the Per Share Merger Consideration Value over the option’s per-share exercise price, multiplied by (2) the number of shares of Stellar Common Stock subject to such stock option immediately prior to the Effective Time. Any Company stock option with a per-share exercise price that is equal to or greater than the Per Share Merger Consideration Value will be cancelled for no consideration. “Per Share Merger Consideration Value” refers to the sum of (1) the Per Share Cash Consideration plus (2) the product of (x) the Exchange Ratio multiplied by (y) the average of the closing sale prices of Prosperity Common Stock on the New York Stock Exchange as reported by The Wall Street Journal for the ten consecutive full trading days ending on and including the fifth trading day immediately preceding the closing date.

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At the Effective Time, each outstanding restricted stock award in respect of Stellar Common Stock subject solely to service-based vesting, repurchase or other lapse restriction will vest and be converted into the right to receive (without interest) the Per Share Merger Consideration.

At the Effective Time, each outstanding restricted unit award in respect of Stellar Common Stock subject to performance-based vesting will vest and be converted into the right to receive (without interest) a cash payment equal to the product of (a) the Per Share Merger Consideration Value multiplied by (b) the number of shares of Stellar Common Stock subject to such performance unit award, with achievement of applicable performance metrics determined to be equal to 100% of the target level (or, in the case of the performance units granted in 2024, 200% of the target level).

Results of Operations

This section provides a comparative discussion of the Company’s results of operations for the two-year period ended December 31, 2025, unless otherwise specified. See “Item 7. Management Discussion and Analysis of Financial Condition and Results of Operations” in our Annual Report on Form 10-K for the year ended December 31, 2024 for a discussion of 2024 versus 2023 results.

Net income was $102.9 million, or $1.99 per diluted common share, for the year ended December 31, 2025 compared with $115.0 million, or $2.15 per diluted common share, for the year ended December 31, 2024, a decrease of $12.1 million, or 10.5%. The decrease in net income was primarily due to a $13.0 million increase in the provision for credit losses, a $6.4 million decrease in net interest income and a $1.3 million decrease in noninterest income, partially offset by a $3.5 million decrease in noninterest expense along with a $5.0 million decrease in the provision for income taxes. See further analysis of the material fluctuations in the related discussions that follow.

Returns on average equity were 6.34% and 7.34%, returns on average assets were 0.97% and 1.08% and efficiency ratios were 62.28% and 61.53% for the years ended December 31, 2025 and 2024, respectively. The efficiency ratio is calculated by dividing total noninterest expense, excluding the amortization of core deposits, by the sum of net interest income plus noninterest income, excluding net gains and losses on sale/write-down of assets.

Net Interest Income

Net interest income before the provision for credit losses for the year ended December 31, 2025 was $401.6 million compared with $408.0 million for the year ended December 31, 2024, a decrease of $6.4 million, or 1.6%. The decrease in net interest income from the prior year was primarily due to the decrease in average interest-earning assets partially offset by the decrease in the cost of interest-bearing liabilities.

Interest income was $574.5 million for the year ended December 31, 2025, a decrease of $27.9 million, or 4.6%, compared to $602.4 million for the year ended December 31, 2024 primarily due to the decrease in the yield on average interest-earnings assets driven partially by lower average loans in the interest-earnings asset mix and lower interest income from purchase accounting adjustments. Average interest-earning assets decreased $59.7 million, or 0.6%, for the year ended December 31, 2025 compared with the year ended December 31, 2024 primarily due a decrease in average loans, partially offset by increases in average securities and deposits in other financial institutions. The yield on average interest-earning assets decreased to 6.00% for the year ended December 31, 2025 from 6.25% for the same period in 2024 as loans decreased as a portion of the interest-earning asset mix. The yield on loans also decreased to 6.68% for the year ended 2025 from 6.89% for the year ended 2024 due to interest income from purchase accounting adjustments and lower interest rates. The yield on average securities increased to 3.75% for the year ended 2025 from 3.34% for the year ended 2024. Additionally, interest income from purchase accounting adjustments was $19.3 million for the year ended December 31, 2025 compared to $33.0 million for the year ended December 31, 2024.

Interest expense was $172.9 million for the year ended December 31, 2025, a decrease of $21.6 million, or 11.1%, compared to $194.4 million for the year ended December 31, 2024. This decrease was primarily due to lower interest rates on interest-bearing deposits and borrowed funds partially offset by an increase in average interest-bearing deposits. The cost of average interest-bearing liabilities decreased to 3.06% for the year ended December 31, 2025 from 3.46% for the same period in 2024. Average interest-bearing deposits increased $127.1 million for the year ended December 31, 2025 compared to the year ended December 31, 2024 due to an increase in interest-bearing demand deposits and money market and savings deposits, partially offset by a decrease in certificates and other time deposits. Additionally, borrowed funds and subordinated debt decreased $102.0 million for the year ended December 31, 2025 compared to the same period in 2024.

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Tax equivalent net interest margin, defined as net interest income adjusted for tax-free income divided by average interest-earning assets, for the year ended December 31, 2025 was 4.20%, a decrease of four basis points compared to 4.24% for the year ended December 31, 2024. The decrease in the net interest margin on a tax equivalent basis was primarily due to decreased yields on earning assets more than offsetting decreased funding costs. The average rate paid on interest-bearing liabilities of 3.06% and the average yield on interest-earning assets of 6.00% for the year ended December 31, 2025 decreased by 40 basis points and 25 basis points, respectively, over the same period in 2024. Tax equivalent adjustments to net interest margin are the result of increasing income from tax-free securities and loans by an amount equal to the taxes that would have been paid if the income were fully taxable based on a 21% federal tax rate for the years ended December 31, 2025, 2024 and 2023, thus making tax-exempt yields comparable to taxable asset yields.

The following table presents, for the periods indicated, the total dollar amount of average balances, interest income from average interest-earning assets and the resultant yields, as well as the interest expense on average interest-bearing liabilities, expressed in both dollars and rates. Average loans include loans on nonaccrual status carrying a zero yield.

(1)The net interest margin is equal to annualized net interest income divided by average interest-earning assets.

(2)Tax-equivalent adjustments have been computed using a federal income tax rate of 21% for the years ended December 31, 2025, 2024 and 2023.

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The following table presents information regarding the dollar amount of changes in interest income and interest expense for the periods indicated for each major component of interest-earnings assets and interest-bearing liabilities and distinguishes between the changes attributable to changes in volume and changes in interest rates. For purposes of this table, changes attributable to both rate and volume that cannot be segregated have been allocated to rate.

Provision for Credit Losses

Our allowance for credit losses is established through charges to income in the form of a provision in order to bring our allowance for credit losses for various types of financial instruments including loans, securities and unfunded commitments to a level deemed appropriate by management. We recorded a provision for credit losses of $10.2 million for the year ended December 31, 2025 compared to a reversal of provision for credit losses of $2.9 million for the year ended December 31, 2024. The provision for credit losses during 2025 was primarily due the increase in specific reserves on individually evaluated loans within the allowance for credit losses model primarily due to the increase in nonperforming loans along with originations during the year on portfolios with higher loss rates. The reversal of provision for credit losses during 2024 was primarily due to the decrease in loans outstanding and changes to the specific reserves within the allowance for credit losses model, among other things. See further discussion of the allowance for the credit losses in “Financial Condition-Asset Quality.”

Net charge-offs were $3.8 million for the year ended December 31, 2025 compared to net charge-offs of $6.7 million for the year ended December 31, 2024.

Noninterest Income

Our primary sources of noninterest income are service charges on deposit accounts, income earned on bank-owned life insurance and debit card and interchange income. Noninterest income does not include loan origination fees which are recognized over the life of the related loan as an adjustment to yield using the interest method.

Noninterest income totaled $21.8 million for the year ended December 31, 2025 compared to $23.0 million for the year ended December 31, 2024, a decrease of $1.3 million, or 5.4%. This decrease was primarily due to losses on sales and write-downs on foreclosed assets recorded during 2025.

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The following table presents, for the periods indicated, the major categories of noninterest income:

(1)Other includes Small Business Investment Company income, FHLB dividends, FRB dividends and wire transfer fees, among other items.

Noninterest Expense

Noninterest expense was $285.5 million for the year ended December 31, 2025 compared to $289.0 million for the year ended December 31, 2024, a decrease of $3.5 million, or 1.2%. The decrease in noninterest expense during 2025 compared to 2024 was primarily due to a $3.2 million decrease in professional fees, a $2.6 million decrease in amortization of intangibles and a $1.4 million decrease in regulatory assessments partially offset by a $3.5 million increase salaries and employee benefits.

The following table presents, for the periods indicated, the major categories of noninterest expense:

(1)Total salaries and employee benefits includes $9.2 million, $10.8 million and $9.9 million in stock-based compensation expense for the years ended December 31, 2025, 2024 and 2023, respectively.

(2)Other includes outside operational services, security, operational losses and other loan expenses, among other items.

Professional fees. Professional fees decreased $3.2 million, or 33.6%, for the year ended December 31, 2025 compared to the year ended December 31, 2024 primarily due to the decrease in consulting fees incurred related to various projects in 2024.

Amortization of intangibles. Amortization of intangibles decreased $2.6 million, or 10.9%, for the year ended December 31, 2025 compared to the year ended December 31, 2024.

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Regulatory assessments and FDIC insurance. Regulatory assessments and FDIC insurance decreased primarily due to the additional special assessment recorded in 2024 for future payments to the FDIC pursuant to the final FDIC rule implementing a special insurance assessment to recover losses to the Deposit Insurance Fund associated with protecting uninsured depositors following several bank failures in 2023.

Salaries and employee benefits. Salaries and benefits were $168.8 million for the year ended December 31, 2025, an increase of $3.5 million, or 2.1%, compared to the year ended December 31, 2024 primarily due to the increase in full-time equivalent employees.

Efficiency Ratio

The efficiency ratio is a supplemental financial measure utilized in management’s internal evaluation of the Company’s performance. We calculate our efficiency ratio by dividing total noninterest expense, excluding the amortization of core deposits, by the sum of net interest income and noninterest income, excluding net gains and losses on the sale/write-down of assets. An increase in the efficiency ratio indicates that more resources are being utilized to generate the same volume of income, while a decrease indicates a more efficient allocation of resources. The Company’s efficiency ratio increased to 62.28% for the year ended December 31, 2025 compared to 61.53% for the year ended December 31, 2024.

We monitor the efficiency ratio in comparison with changes in our total assets and loans, and we believe that maintaining or reducing the efficiency ratio during periods of growth, demonstrates the scalability of our operating platform. We expect to continue to benefit from our scalable platform in future periods as we continue to monitor overhead expenses necessary to support our growth.

Income Taxes

The amount of federal and state income tax expense is influenced by the amount of pre-tax income, the amount of tax-exempt income and other nondeductible expenses. Income tax expense decreased 16.8%, to $24.9 million for the year ended December 31, 2025 compared with $30.0 million for the same period in 2024. The effective tax rates were 19.5% and 20.7% for the years ended December 31, 2025 and 2024, respectively. The effective income tax rates differed from the U.S. statutory federal income tax rate of 21% during 2025 and 2024 primarily due to the effect of tax-exempt income from securities, loans and life insurance policies, among other things, and their relative proportion to total pre-tax net income.

The One Big Beautiful Bill Act (“OBBBA”) was enacted on July 4, 2025. Among other things, the new law makes permanent certain expiring business tax provisions of the Tax Cuts and Jobs Act (“TCJA”). The OBBBA did not have a significant impact on our financial statements, though some minor operational changes were necessary to support new information reporting requirements. The OBBBA also significantly changes U.S. tax law related to foreign operations and certain tax credits; however, such changes do not currently impact us as the Company does not have foreign operations. As part of the OBBBA, the Company purchased transferrable energy tax credits in December 2025. The credits were purchased at a discount relative to the actual value of the credits obtained and reduced the Company’s income tax expense by $937 thousand in 2025.

Financial Condition

Loan Portfolio

At December 31, 2025, total loans were $7.30 billion, a decrease of $139.3 million, or 1.9%, compared with December 31, 2024 primarily due to decreases in commercial real estate, commercial real estate construction and land development and residential construction loans. Total loans as a percentage of deposits were 80.9% and 81.5% as of December 31, 2025 and December 31, 2024, respectively. Total loans as a percentage of assets were 67.6% and 68.2% as of December 31, 2025 and December 31, 2024, respectively.

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The following table summarizes our loan portfolio by type of loan as of the dates indicated:

Our lending activities originate from the efforts of our bankers with an emphasis on lending to individuals, professionals, small- to medium-sized businesses and commercial companies generally located in our market. Our strategy for credit risk management generally includes well-defined, centralized credit policies, uniform underwriting criteria and ongoing risk monitoring and review processes for credit exposures. The strategy generally emphasizes regular credit examinations and management reviews of loans. We have certain lending policies and procedures in place that are designed to maximize loan income within an acceptable level of risk. We maintain an independent loan review department which includes third-party loan review services to review the credit risk on a periodic basis. The internal loan review department focuses on credits not reviewed by the third-party loan reviewer to ensure more complete coverage of credit risk. Results of these reviews are presented to management and the risk committee of the Board of Directors. The loan review process complements and reinforces the risk identification and assessment decisions made by bankers and credit personnel and contained in our policies and procedures. The principal categories of our loan portfolio are discussed below.

Commercial and Industrial. We make commercial and industrial loans in our market area that are underwritten on the basis of the borrower’s ability to service the debt from income. The increased risk in these loans derives from the expectation that commercial and industrial loans generally are serviced principally from the operations of the business, which may not be successful and from the type of collateral securing these loans. Commercial and industrial loans are typically collateralized by general business assets including, among other things, accounts receivable, inventory and equipment and are generally backed by a personal guaranty of the borrower or principal. This collateral may decline in value more rapidly than we anticipate, exposing us to increased credit risk. As a result, commercial and industrial loans require more extensive underwriting and servicing than other types of loans. Our commercial and industrial loan portfolio increased $114.3 million, or 8.4%, to $1.48 billion as of December 31, 2025 compared to $1.36 billion as of December 31, 2024.

Commercial Real Estate (Including Multi-Family Residential). We make loans to finance the purchase or ownership of commercial real estate. As of December 31, 2025, our commercial real estate loans comprised 51.6% of our loan portfolio. Repayment is generally dependent on the successful operations of the property and may be impacted by general economic conditions, including fluctuations in the value of real estate, vacancy rates and unemployment trends. The collateral securing these loans is typically more difficult to liquidate due to the fluctuation of real estate values. As of December 31, 2025 and December 31, 2024, 47.7% and 47.4%, respectively, of our commercial real estate loans were owner-occupied. Our commercial real estate loan portfolio decreased $101.9 million, or 2.6%, to $3.77 billion as of December 31, 2025 from $3.87 billion as of December 31, 2024.

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The following table summarizes our commercial real estate loan portfolio by type of property securing the loans at December 31, 2025.

As of December 31, 2025, our commercial real estate (including multi-family residential) loan portfolio included $286.3 million of multi-family community development loans with associated tax credits, which fund Texas based projects to promote affordable housing, compared to $233.3 million as of December 31, 2024.

Commercial Real Estate Construction and Land Development. We make commercial real estate construction and land development loans to fund commercial construction, land acquisition and real estate development construction. Construction loans involve additional risks as they often involve the disbursement of funds with the repayment dependent on the ultimate success of the project’s completion. Sources of repayment for these loans may be pre-committed permanent financing or sale of the developed property. The loans in this portfolio are monitored closely by management. Due to uncertainties inherent in estimating construction costs, the market value of the completed project and the effects of governmental regulation on real property, it can be difficult to accurately evaluate the total funds required to complete a project and the related loan to value ratio. As a result of these uncertainties, construction lending often includes the disbursement of substantial funds with repayment dependent, in part, on the success of the ultimate project rather than the ability of a borrower or guarantor to repay the loan. As of December 31, 2025 and December 31, 2024, 14.6% and 13.1%, respectively, of our commercial real estate construction and land development loans were owner-occupied. Our commercial real estate construction and land development loans decreased $124.7 million, or 14.8%, to $720.8 million as of December 31, 2025 compared to $845.5 million as of December 31, 2024.

As of December 31, 2025, our commercial real estate construction and land development loan portfolio included $102.4 million of construction and development loans to support multi-family community development loans with associated tax credits, which fund Texas based projects to promote affordable housing, compared to $137.1 million as of December 31, 2024.

1-4 Family Residential (Including Home Equity). Our residential real estate loans include the origination of 1-4 family residential mortgage loans (including home equity and home improvement loans and home equity lines of credit) collateralized by owner-occupied residential properties located in our market areas. Our residential real estate portfolio (including home equity) increased $20.7 million, or 1.9%, to $1.14 billion as of December 31, 2025 from $1.12 billion as of December 31, 2024.

Residential Construction. We make residential construction loans to home builders and individuals to fund the construction of single-family residences with the understanding that such loans will be repaid from the proceeds of the sale of the homes by builders or with the proceeds of a mortgage loan. These loans are secured by the real property being built and are made based on our assessment of the value of the property on an as-completed basis. Our residential construction loans portfolio decreased $33.3 million, or 21.1%, to $124.7 million as of December 31, 2025 from $158.0 million as of December 31, 2024.

Consumer and Other. Our consumer and other loan portfolio is made up of loans made to individuals for personal purposes and deferred fees and costs on all loan types. Generally, consumer loans entail greater risk than residential real estate loans because they may be unsecured or if secured the value of the collateral, such as an automobile or boat, may be more difficult to assess and

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more likely to decrease in value than real estate. In such cases, any repossessed collateral for a defaulted consumer loan may not provide an adequate source of repayment for the outstanding loan balance. The remaining deficiency often does not warrant further substantial collection efforts against the borrower beyond obtaining a deficiency judgment. In addition, consumer loan collections are dependent on the borrower’s continuing financial stability, and thus are more likely to be adversely affected by job loss, divorce, illness or personal bankruptcy. Furthermore, the application of various federal and state laws may limit the amount which can be recovered on such loans. Our consumer and other loan portfolio decreased $14.3 million, or 15.9%, to $76.1 million as of December 31, 2025 from $90.4 million as of December 31, 2024.

The contractual maturity ranges of total loans in our loan portfolio and the amount of such loans with predetermined interest rates in each maturity range and the amount of loans with predetermined (fixed) interest rates and floating interest rates in each maturity range, in each case as of the date indicated, are summarized in the following tables:

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Concentrations of Credit

The vast majority of our lending activity occurs in the Houston and Beaumont MSAs. Our loans are primarily secured by real estate, including commercial and residential construction, owner-occupied and nonowner-occupied and multi-family commercial real estate, raw land and other real estate based loans located in the Houston and Beaumont MSAs. As of December 31, 2025 and 2024, commercial real estate and commercial construction loans represented 61.5% and 63.4%, respectively, of our total loans.

Asset Quality

We have procedures in place to assist us in maintaining the overall quality of our loan portfolio. We have established underwriting guidelines to be followed by our officers and monitor our delinquency levels for any negative or adverse trends.

Nonperforming Assets

Nonperforming assets totaled $60.0 million, or 0.56% of total assets at December 31, 2025, compared to $38.9 million, or 0.36% of total assets at December 31, 2024. Nonaccrual loans consisted of 171 separate credits at December 31, 2025 compared to 101 separate credits at December 31, 2024.

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The following table presents information regarding nonperforming assets as of the dates indicated:

(1)Troubled loan modifications in the table above represent the balance at the end of the respective period for those loans that are not already presented as a nonperforming loan.

Allowance for Credit Losses

The allowance for credit losses is a valuation allowance that is established through charges to earnings in the form of a provision for (or reversal of) credit losses calculated in accordance with ASC Topic 326- Measurement of Credit Losses on Financial Instruments (“ASC 326”), that is deducted from the amortized cost basis of certain assets to present the net amount expected to be collected. The amount of each allowance account represents management’s best estimate of current expected credit losses on these financial instruments considering available information, from internal and external sources, relevant to assessing exposure to credit loss over the contractual term of the instrument. Relevant available information includes historical credit loss experience, current conditions and reasonable and supportable forecasts. While historical credit loss experience provides the basis for the estimation of expected credit losses, adjustments to historical loss information may be made for differences in current portfolio-specific risk characteristics, environmental conditions or other relevant factors. While management utilizes its best judgment and information available, the ultimate adequacy of our allowance accounts is dependent upon a variety of factors beyond our control, including the performance of our portfolios, the economy, changes in interest rates and the view of the regulatory authorities toward classification of assets. For additional information regarding critical accounting estimates and policies, refer to “Critical Accounting Estimates” in this section, Note 1 – Nature of Operations and Summary of Significant Accounting and Reporting Policies and Note 4 – Loans and Allowance for Credit Losses in the accompanying notes to the consolidated financial statements.

Allowance for Credit Losses on Loans

The allowance for credit losses on loans represents management’s estimates of current expected credit losses in the loan portfolio. Pools of loans with similar risk characteristics are collectively evaluated, while loans that no longer share risk characteristics with loan pools are evaluated individually.

At December 31, 2025, our allowance for credit losses on loans was $83.6 million, or 1.15% of total loans, compared with $81.1 million, or 1.09% of total loans, as of December 31, 2024. The increase in the allowance for credit losses on loans during 2025 primarily resulted from changes to the specific reserves within the allowance for credit losses model primarily due to the increase in nonperforming loans, among other things.

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The following table presents an analysis of the allowance for credit losses on loans and other related data as of and for the periods indicated:

Allowance for Credit Losses on Unfunded Commitments

The allowance for credit losses on unfunded commitments estimates current expected credit losses over the contractual period in which there is exposure to credit risk via a contractual obligation to extend credit, unless that obligation is unconditionally cancellable by us. The allowance for credit losses on unfunded commitments is a liability account reported as a component of other liabilities in our consolidated balance sheets and is adjusted as a provision for credit loss expense. The estimate includes consideration of the likelihood that funding will occur and an estimate of expected credit losses on the commitments expected to fund. The estimate of commitments expected to fund is affected by historical analysis looking at utilization rates. The expected credit loss rates applied to the commitments expected to fund are affected by the general valuation allowance utilized for outstanding balances with the same underlying assumptions and drivers. At December 31, 2025, our allowance for credit losses on unfunded commitments was $16.2 million compared to $12.4 million at December 31, 2024.

See Note 4 – Loans and Allowance for Credit Losses in the accompanying notes to the consolidated financial statement for additional information regarding how we estimate and evaluate the credit risk in our loan portfolio.

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Available for Sale Securities

We use our securities portfolio to provide a source of liquidity, to provide an appropriate return on funds invested, to manage interest rate risk and to meet pledging and regulatory capital requirements. As of December 31, 2025, the carrying amount of investment securities totaled $2.20 billion, an increase of $525.4 million, or 31.4%, compared with $1.67 billion as of December 31, 2024. Securities represented 20.3% and 15.3% of total assets as of December 31, 2025 and 2024, respectively.

All of the securities in our securities portfolio are classified as available for sale. Securities classified as available for sale are measured at fair value in the financial statements with unrealized gains and losses reported, net of tax, as accumulated comprehensive income or loss until realized. Interest earned on securities is included in interest income. The following tables summarize the amortized cost and fair value of the securities in our securities portfolio as of the dates shown:

Investment securities classified as available for sale or held to maturity are evaluated for expected credit losses under ASC Topic 326. See Note 3 – Securities in the accompanying notes to the consolidated financial statements for additional information. Management does not have the intent to sell any of these securities and believes that it is more likely than not that the Company will not have to sell any such securities before a recovery of cost. The fair value is expected to recover as the securities approach their maturity date or repricing date or if market yields for such investments decline. Accordingly, as of December 31, 2025, management believes that the unrealized losses detailed in the previous table are due to noncredit-related factors, including changes in interest rates and other market conditions, and therefore, no losses have been recognized in the Company’s consolidated statements of income.

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The following table summarizes the contractual maturity of securities and their weighted average yields as of the dates indicated. The contractual maturity of a mortgage-backed security is the date at which the last underlying mortgage matures. Available for sale securities are shown at amortized cost. For purposes of the tables below, the yields on municipal securities were calculated on a tax equivalent basis.

The contractual maturity of mortgage-backed securities and collateralized mortgage obligations is not a reliable indicator of their expected life because borrowers may have the right to prepay their obligations. Mortgage-backed securities and collateralized mortgage obligations are typically issued with stated principal amounts and are backed by pools of mortgage loans with varying maturities. The term of the underlying mortgages and loans may vary significantly due to the ability of a borrower to prepay and, in particular, monthly pay downs on mortgage-backed securities tend to cause the average life of the securities to be much different than the stated contractual maturity. During a period of increasing interest rates, fixed rate mortgage-backed securities do not tend to experience heavy prepayments of principal and, consequently, the average life of this security will be lengthened. If interest rates begin to fall, prepayments may increase, thereby shortening the estimated life of the security.

As of December 31, 2025 and 2024, we did not own securities of any one issuer (other than the U.S. government and its agencies or sponsored entities) for which the aggregate adjusted cost exceeded 10% of our consolidated shareholders’ equity.

The average yield of our securities portfolio was 3.75% for the year ended December 31, 2025 compared with 3.34% for the year ended December 31, 2024. The increase in average yield during 2025 compared to 2024 was primarily due to security purchases during the year increasing the mix of higher-yielding securities within the portfolio.

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Goodwill and Core Deposit Intangibles

Goodwill was $497.3 million as of both December 31, 2025 and 2024. Goodwill resulting from business combinations represents the excess of the consideration paid over the fair value of the net assets acquired. Goodwill is assessed annually for impairment and on an interim basis if an event occurs or circumstances change that would indicate that the carrying amount of the asset may not be recoverable.

Core deposit intangibles, net, as of December 31, 2025 was $71.0 million compared to $92.5 million as of December 31, 2024. Core deposit intangibles are amortized using the straight-line or an accelerated method over the estimated useful life of seven to ten years.

Deposits

Our lending and investing activities are primarily funded by deposits. We offer a variety of deposit accounts having a wide range of interest rates and terms including demand, savings, money market and certificates and other time accounts. We rely primarily on convenient locations, personalized service and our customer relationships to attract and retain these deposits. We seek customers that will engage in both a lending and deposit relationship with us.

Total deposits at December 31, 2025 were $9.02 billion, a decrease of $106.9 million, or 1.2%, compared with $9.13 billion at December 31, 2024 primarily driven by seasonality, industry-wide pressures and the maintenance of pricing discipline in an intensely competitive market for deposits. Noninterest-bearing deposits at December 31, 2025 were $3.41 billion, a decrease of $168.3 million, or 4.7%, compared with $3.58 billion at December 31, 2024. Interest-bearing deposits at December 31, 2025 were $5.61 billion, an increase of $61.4 million, or 1.1%, compared with $5.55 billion at December 31, 2024. Our ratio of noninterest-bearing deposits to total deposits was 37.8% and 39.2% for the years ended December 31, 2025 and 2024, respectively. Deposits include fully collateralized public funds of $1.11 billion and $1.44 billion at December 31, 2025 and 2024, respectively.

The following table presents the daily average balances and weighted-average rates paid on deposits for the periods indicated:

The following table sets forth the amount of time deposits that met or exceeded the FDIC insurance limit of $250 thousand by time remaining until maturity at December 31, 2025 (in thousands):

Borrowings

The Company has an available line of credit with the FHLB, which allows the Company to borrow on a collateralized basis. FHLB advances are used to manage liquidity as needed. The advances are secured by blanket liens on certain loans. Maturing advances are replaced by drawing on available cash, making additional borrowings or through increased customer deposits. At

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December 31, 2025, the Company had total borrowing capacity of $3.17 billion of which $997.1 million was available under the agreement and $2.17 billion was outstanding pursuant to FHLB letters of credit. At December 31, 2025 and 2024, the Company had no FHLB advances outstanding.

At December 31, 2025, the Company had FHLB letters of credit pledged as collateral for public and other deposits of state and local government agencies expire in the following periods (in thousands):

Subordinated Debt

Junior Subordinated Debentures

In connection with the acquisition of F&M Bancshares, Inc. in 2015, the Company assumed Farmers & Merchants Capital Trust II and Farmers & Merchants Capital Trust III. Each of the trusts is a capital or statutory business trust organized for the sole purpose of issuing trust securities and investing the proceeds in the Company’s junior subordinated debentures. The preferred trust securities of each trust represent preferred beneficial interests in the assets of the respective trusts and are subject to mandatory redemption upon payment of the junior subordinated debentures held by the trust. The common securities of each trust are wholly owned by the Company. Each trust’s ability to pay amounts due on the trust preferred securities is solely dependent upon the Company making payment on the related junior subordinated debentures. The debentures, which are the only assets of each trust, are subordinate and junior in right of payment to all of the Company’s present and future senior indebtedness. The Company has fully and unconditionally guaranteed each trust’s obligations under the trust securities issued by each trust to the extent not paid or made by such trust, provided such trust has funds available for such obligations. The trust preferred securities bear a floating rate of interest equal to 3-Month SOFR plus a spread adjustment. The junior subordinated debentures are included in Tier 1 capital under current regulatory guidelines and interpretations. Under the provisions of each issue of the debentures, the Company has the right to defer payment of interest on the debentures at any time, or from time to time, for periods not exceeding five years. If interest payments on either issue of the debentures are deferred, the distributions on the applicable trust preferred securities and common securities will also be deferred.

A summary of pertinent information related to the Company’s issuances of junior subordinated debentures outstanding at December 31, 2025 is set forth in the table below:

(1)    All debentures were callable at December 31, 2025.

Subordinated Notes

In December 2017, the Bank issued $40.0 million aggregate principal amount of Fixed-to-Floating Rate Subordinated Notes (the “Bank Notes”) due December 15, 2027 and bore a floating rate of interest equal to 3-Month SOFR plus a 3.03% spread adjustment. In December 2024, the Bank redeemed the Bank Notes at a redemption price equal to 100% of the principal amount of Bank Notes plus accrued and unpaid interest.

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In September 2019, Stellar issued $60.0 million aggregate principal amount of Fixed-to-Floating Rate Subordinated Notes (the “Company Notes”) due October 1, 2029. As of December 31, 2025, the Company Notes bore at a floating rate equal to 3-Month SOFR plus 3.13% and a spread adjustment for each quarterly interest period, payable quarterly in arrears on January 1, April 1, July 1 and October 1 of each year. On October 1, 2025, the Company redeemed $30.0 million of the Company Notes. The redemption price for the Company Notes was equal to 100% of the principal amount of the Company Notes redeemed, plus $1.2 million for accrued and unpaid interest up to, but excluding, the redemption date. Any future redemptions will be at a redemption price equal to 100% of the principal amount of Company Notes being redeemed, plus accrued and unpaid interest, and will be subject to, and require, prior regulatory approval. The Company Notes are not subject to redemption at the option of the holders.

Credit Agreement

On December 13, 2024, the Company renewed its loan agreement with another financial institution (the “Loan Agreement”), that provides for a $75.0 million revolving line of credit. At December 31, 2025, there were no outstanding borrowings on this line of credit and no draws were taken on this line of credit during 2025 or 2024. Interest accrues on outstanding borrowings at a per annum rate equal to 3-month SOFR plus 2.75% calculated in accordance with the terms of the revolving promissory note and payable quarterly through the first 24 months. The entire outstanding balance and unpaid interest is payable in full on December 13, 2033, the maturity date. The Company may prepay the principal amount of the line of credit without premium or penalty. The obligations of the Company under the Loan Agreement are secured by a pledge of all of the issued and outstanding shares of capital stock of the Bank.

Covenants made under the Loan Agreement include, among other things, while there are obligations outstanding under Loan Agreement, the Company shall maintain a cash flow to debt service (as defined in the Loan Agreement) of not less than 1.25, the Bank’s Texas Ratio (as defined in the Loan Agreement) not to exceed 20.0%, the Bank shall maintain a Tier 1 Leverage Ratio (as defined under the Loan Agreement) of at least 8.0% and includes restrictions on the ability of the Company and its subsidiaries to incur certain additional debt. As of December 31, 2025, the Company believes it was in compliance with all such debt covenants and had not been made aware of any noncompliance by the lender.

Liquidity and Capital Resources

Liquidity

Liquidity is the measure of our ability to meet the cash flow requirements of depositors and borrowers, while at the same time meeting our operating, capital and strategic cash flow needs and to maintain reserve requirements to operate on an ongoing basis and manage unexpected events, all at a reasonable cost. During the years ended December 31, 2025 and 2024, our liquidity needs have primarily been met by deposits, borrowed funds and securities. The Bank has access to purchased funds from correspondent banks, the Federal Reserve discount window and advances from the FHLB, on a collateralized basis, are available under a security and pledge agreement to take advantage of investment opportunities.

Liquidity risk management is an important element in our asset/liability management process. Our liquidity position is continuously monitored and adjustments are made to the balance between sources and uses of funds as deemed appropriate. We regularly model liquidity stress scenarios to assess potential liquidity outflows or funding problems resulting from economic disruptions, volatility in the financial markets, unexpected credit events or other significant occurrences deemed problematic by management. Liquidity stress scenarios are incorporated into our contingency funding plan, which provides the basis for the identification of our liquidity needs.

Our largest source of funds is deposits and our largest use of funds is loans. Our average deposits decreased $6.2 million, or 0.1%, for the year ended December 31, 2025 compared to the year ended December 31, 2024. Our average loans decreased $449.0 million, or 5.8%, for the year ended December 31, 2025 compared to the year ended December 31, 2024. We predominantly invest excess deposits in Federal Reserve Bank of Dallas balances, securities, interest-bearing deposits at other banks or other short-term liquid investments until the funds are needed to fund loan growth. Our securities portfolio had a weighted average life of 6.4 years and 7.2 years at December 31, 2025 and 2024, respectively.

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The following table illustrates, during the periods presented, the mix of our funding sources and the average assets in which those funds are invested as a percentage of our average total assets for the periods indicated.

As of December 31, 2025 and 2024, we had outstanding commitments to extend credit of $2.10 billion and $1.70 billion, respectively, and commitments associated with outstanding letters of credit of $65.6 million and $43.6 million, respectively. Since commitments associated with commitments to extend credit and outstanding letters of credit may expire unused, the total outstanding may not necessarily reflect the actual future cash funding requirements. At December 31, 2025 and 2024, we had FHLB letters of credit in the amount of $2.17 billion and $2.10 billion, respectively, pledged as collateral for public and other deposits of state and local government agencies. See Note 9 – Borrowings and Borrowing Capacity to the accompanying consolidated financial statements.

Total immediate contingent funding sources, including unrestricted cash, available-for-sale securities that are not pledged and total available borrowing capacity was $3.95 billion, or 43.7%, of total deposits at December 31, 2025. Estimated uninsured deposits net of collateralized deposits were 45.7% of total deposits at December 31, 2025. Including policy-driven capacity for brokered deposits, the Bank would have been able to add approximately $2.26 billion to its contingent sources of liquidity, bringing total contingent funding sources to approximately $6.2 billion, or 68.8%, of deposits at December 31, 2025.

As of December 31, 2025 and 2024, we had no exposure to future cash requirements associated with known uncertainties or capital expenditures of a material nature.

In the ordinary course of business, we have entered into contractual obligations and have made other commitments to make future payments. Refer to the accompanying notes to accompanying consolidated financial statements for the expected timing of such payments as of December 31, 2025. These include payments related to (1) operating leases (Note 5 – Premises and Equipment and Leases), (2) time deposits with stated maturity dates (Note 7 – Deposits), (3) borrowings (Note 9 – Borrowings and Borrowing Capacity) and (4) commitments to extend credit and standby letters of credit (Note 13 – Off-Balance Sheet Arrangements, Commitments and Contingencies).

Commitments to Extend Credit. We enter into contractual commitments to extend credit, normally with fixed expiration dates or termination clauses, at specified rates and for specific purposes. Substantially all of our commitments to extend credit are contingent upon customers maintaining specific credit standards at the time of loan funding. We minimize our exposure to loss under these commitments by subjecting them to credit approval and monitoring procedures. The amount and type of collateral obtained, if considered necessary by us, upon extension of credit, is based on management’s credit evaluation of the customer. Management assesses the credit risk associated with certain commitments to extend credit in determining the level of the allowance for credit losses.

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Standby Letters of Credit. Standby letters of credit are written conditional commitments issued by the Company to guarantee the performance of a customer to a third-party. In the event of nonperformance by the customer, the Company has the rights to the underlying collateral. The credit risk to the Company in issuing letters of credit is substantially similar to that involved in extending loan facilities to its customers. The Company’s policy for obtaining collateral, and the nature of such collateral, is substantially similar to that involved in making commitments to extend credit.

Capital Resources

Capital management consists of providing equity to support our current and future operations. We are subject to capital adequacy requirements imposed by the Federal Reserve. The Federal Reserve has adopted risk-based capital requirements for assessing bank holding company and bank capital adequacy. These standards define capital and establish minimum capital requirements in relation to assets and off-balance sheet exposure, adjusted for credit risk. The risk-based capital standards currently in effect are designed to make regulatory capital requirements more sensitive to differences in risk profiles among bank holding companies and banks, to account for off-balance sheet exposure and to minimize disincentives for holding liquid assets. Assets and off-balance sheet items are assigned to broad risk categories, each with appropriate relative risk weights. The resulting capital ratios represent capital as a percentage of total risk-weighted assets and off-balance sheet items.

Under current guidelines, the minimum ratio of total capital to risk-weighted assets (which are primarily the credit risk equivalents of balance sheet assets and certain off-balance sheet items such as standby letters of credit) is 8.0%. At least half of total capital must be composed of Tier 1 capital, which includes common shareholders’ equity (including retained earnings), less goodwill, other disallowed intangible assets and disallowed deferred tax assets, among other items. The Federal Reserve also has adopted a minimum leverage ratio, requiring Tier 1 capital of at least 4.0% of average quarterly total consolidated assets, net of goodwill and certain other intangible assets, for all but the most highly rated bank holding companies. The federal banking agencies have also established risk-based and leverage capital guidelines that FDIC-insured depository institutions are required to meet. These regulations are generally similar to those established by the Federal Reserve for bank holding companies.

Under the Federal Deposit Insurance Act, the federal bank regulatory agencies must take “prompt corrective action” against undercapitalized U.S. depository institutions. U.S. depository institutions are assigned one of five capital categories: “well- capitalized,” “adequately capitalized,” “undercapitalized,” “significantly undercapitalized” and “critically undercapitalized,” and are subjected to different regulation corresponding to the capital category within which the institution falls. A depository institution is deemed to be “well capitalized” if the banking institution has a total risk-based capital ratio of 10.0% or greater, a Tier 1 risk-based capital ratio of 8.0% or greater, a common equity Tier 1 capital ratio of 6.5% and a leverage ratio of 5.0% or greater, and the institution is not subject to an order, written agreement, capital directive or prompt corrective action directive to meet and maintain a specific level for any capital measure. Under certain circumstances, a well-capitalized, adequately capitalized or undercapitalized institution may be treated as if the institution were in the next lower capital category.

Failure to meet capital guidelines could subject the institution to a variety of enforcement remedies by federal bank regulatory agencies, including termination of deposit insurance by the FDIC, restrictions on certain business activities and appointment of the FDIC as conservator or receiver. As of December 31, 2025 and 2024, the Bank was well capitalized. Total shareholders' equity was $1.67 billion at December 31, 2025 compared with $1.61 billion at December 31, 2024, an increase of $60.8 million. This increase was primarily due to net income of $102.9 million, partially offset by dividends paid of $29.3 million, or $0.57 per common share, during 2025.

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The following table provides a comparison of the Company’s and the Bank’s leverage and risk-weighted capital ratios as of December 31, 2025 to the minimum and well-capitalized regulatory standards, as well as with the capital conservation buffer:

Asset/Liability Management and Interest Rate Risk

Our asset liability and interest rate risk policy provides management with guidelines for effective balance sheet management. We have established a measurement system for monitoring our net interest rate sensitivity position. We seek to manage our sensitivity position within our established guidelines.

As a financial institution, a component of the market risk that we face is interest rate volatility. Fluctuations in interest rates will ultimately impact both the level of income and expense recorded on most of our assets and liabilities, and the market value of all interest-earning assets and interest-bearing liabilities, other than those which have a short term to maturity. Interest rate risk is the potential for economic losses due to future interest rate changes. These economic losses can be reflected as a loss of future net interest income and/or a loss of current fair market values. The objective is to measure the effect on net interest income and to adjust the balance sheet to minimize the inherent risk while at the same time maximizing income.

Based upon the nature of our operations, we are not subject to foreign exchange rate or commodity price risk. We do not own any trading assets. We manage our exposure to interest rates by structuring our balance sheet in the ordinary course of a community banking business. The Company enters into interest rate swaps as an accommodation to customers.

Our exposure to interest rate risk is managed by our Asset Liability Committee (“ALCO”). The ALCO formulates strategies based on appropriate levels of interest rate risk. In determining the appropriate level of interest rate risk, the ALCO considers the impact on earnings and capital of the current outlook on interest rates, potential changes in interest rates, regional economies, liquidity, business strategies and other factors. The ALCO meets regularly to review, among other things, the sensitivity of assets and liabilities to interest rate changes, the book and market values of assets and liabilities, unrealized gains and losses, purchase and sale activities, commitments to originate loans and the maturities of investments and borrowings. Additionally, the ALCO reviews liquidity, cash flow flexibility, maturities of deposits and consumer and commercial deposit activity.

We use an interest rate risk simulation model and shock analysis to test the interest rate sensitivity of net interest income and the balance sheet, respectively. Where applicable, instruments on the balance sheet are modeled at the instrument level, incorporating all relevant attributes such as next reset date, reset frequency and call dates, as well as prepayment assumptions for loans and securities and decay rates for nonmaturity deposits. Assumptions based on past experience are incorporated into the model for nonmaturity deposit account decay rates. The assumptions used are inherently uncertain and, as a result, the model cannot precisely measure future net interest income or precisely predict the impact of fluctuations in market interest rates on net interest income. Actual results will

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differ from the model’s simulated results due to timing, magnitude and frequency of interest rate changes as well as changes in market conditions and the application and timing of various management strategies.

We utilize static balance sheet rate shocks to estimate the potential impact on net interest income of changes in interest rates under various rate scenarios. This analysis estimates a percentage of change in the metric from the stable rate base scenario versus alternative scenarios of rising and falling market interest rates by instantaneously shocking a static balance sheet.

The following table summarizes the simulated change in the economic value of equity and net interest income over a 12-month horizon as of the dates indicated:

These results are primarily due to the size of our cash position, the size and duration of our loan and securities portfolio, the duration of our borrowings and the expected behavior of demand, money market and savings deposits during such rate fluctuations. During 2025, changes in our overall interest rate profile were driven by the increase in certain interest-bearing deposits and securities along with a decrease in noninterest-bearing deposits, loans and cash and cash equivalents.