PROSPERITY BANCSHARES, INC.® REPORTS FIRST QUARTER 2026 EARNINGS

PROSPERITY BANCSHARES, INC.® REPORTS FIRST QUARTER 2026 EARNINGS HOUSTON, April 29, 2026 /PRNewswire/ -- Prosperity Bancshares, Inc. ® (NYSE: PB) ("Prosperity Bancshares"), the parent company of Prosperity Bank ® (collectively, "Prosperity"), reported net income of $116.3 million for the quarter ended March 31, 2026, compared with $130.2 million for the same period in 2025. Net income per diluted common share was $1.16 for the quarter ended March 31, 2026, compared with $1.37 for the same period in 2025. On January 1, 2026, American Bank Holding Corporation ("American") merged with Prosperity Bancshares and American Bank, N.A. ("American Bank") merged with Prosperity Bank (collectively, the "American Merger"), and on February 1, 2026, Southwest Bancshares, Inc. ("Southwest") merged with Prosperity Bancshares and Texas Partners Bank ("Texas Partners") merged with Prosperity Bank (collectively, the "Southwest Merger", and together with the American Merger, the "Mergers"). During the first quarter of 2026, Prosperity incurred merger related expenses of $42.5 million, or $0.34 (1)per diluted common share. Excluding these charges, net income was $149.9 (1) million and earnings per diluted common share was $1.50 (1) for the first quarter of 2026. Additionally, during the first quarter of 2026, loans, excluding Warehouse Purchase Program loans, increased $3.354 billion or 16.4%, and deposits increased $4.150 billion or 14.6%, with both increases primarily due to the Mergers. The annualized return on first quarter average assets was 1.10%. Nonperforming assets remain low at 0.33% of first quarter average interest-earning assets.

"The first quarter of 2026 was impactful for the company and I am excited to announce that during the quarter we completed the merger of American Bank Holding Corporation on January 1, 2026, completed the merger of Southwest Bancshares, Inc. on February 1, 2026 and announced the merger of Stellar Bancorp, Inc. on January 28, 2026, for which we have now received all necessary regulatory approvals and expect to complete on July 1, 2026. Additionally, we completed a core system conversion in February," said David Zalman, Prosperity's Senior Chairman and Chief Executive Officer.

"We and others believe that Prosperity is doing the right thing. Prosperity has been ranked as one of Forbes America's Best Banks for 2026, and since the list's inception in 2010, was ranked in the Top 10 for 14 consecutive years. Prosperity has also been recognized by Newsweek as one of "America's Best Regional Banks" and was ranked 15th in S&P Global Market Intelligence's "Top 50 US Public Bank Ranking" for 2025," continued Zalman.

"In an effort to continue to enhance shareholder value, Prosperity Bancshares repurchased approximately 837,000 shares of its common stock at an average weighted price of $68.15 per share for a total of $57.1 million during the first quarter of 2026," added Zalman.

"Texas and Oklahoma continue to benefit from strong economies and are home to 57 Fortune 500 headquartered companies. Texas also benefits from diversification in various industries, including energy (oil, gas, renewables), technology, manufacturing, trade/logistics (major ports), healthcare and finance. Further, its business-friendly environment, no state income tax, population growth that support spending and workforce expansion and key role in trade and cross-border commerce position it well for 2026 and the future," stated Zalman.

"While Texas continues to outperform the Unites States on output growth, the labor market has cooled after years of expansion. The growth in 2026 is expected to be steady, although the state's size, diversity and policy advantages position it well for a rebound," concluded Zalman.

Results of Operations for the Three Months Ended March 31, 2026

For the three months ended March 31, 2026, net income was $116.3 million (2) or $1.16 per diluted common share compared with $130.2 million (3) or $1.37 per diluted common share for the same period in 2025. On a linked quarter basis, net income was $116.3 million (2) or $1.16 per diluted common share for the three months ended March 31, 2026, compared with $139.9 million (4) or $1.49 per diluted common share for the three months ended December 31, 2025. Net income and net income per diluted common share for the first quarter of 2026 were impacted by the Mergers and merger related expenses of $42.5 million. Excluding these charges, net income was $149.9 (1) million and earnings per diluted common share was $1.50 (1) for the three months ended March 31, 2026. Annualized returns on average assets, average common equity and average tangible common equity for the three months ended March 31, 2026 were 1.10%, 5.70% and 10.59% (1), respectively. Excluding merger related expenses, net of tax, annualized returns on average assets, average common equity and average tangible common equity for the three months ended March 31, 2026, were 1.42% (1), 7.35% (1) and 13.65% (1), respectively. Prosperity's efficiency ratio (excluding net gains and losses on the sale, write-down or write-up of assets and securities) was 59.16% (1) for the three months ended March 31, 2026, and excluding merger related expenses, the efficiency ratio was 47.58% (1).

Net interest income before provision for credit losses was $321.2 million for the three months ended March 31, 2026, compared with $265.4 million for the same period in 2025, an increase of $55.8 million or 21.0%. The net interest margin on a tax equivalent basis was 3.51% for the three months ended March 31, 2026, compared with 3.14% for the same period in 2025. Net interest income before provision for credit losses increased $46.2 million or 16.8% to $321.2 million for the three months ended March 31, 2026, compared with $275.0 million for the three months ended December 31, 2025. The net interest margin on a tax equivalent basis was 3.51% for the three months ended March 31, 2026, compared with 3.30% for the three months ended December 31, 2025. The change for both periods were primarily due to the repricing of assets and the impact of the Mergers.

Noninterest income was $46.5 million for the three months ended March 31, 2026, compared with $41.3 million for the same period in 2025, an increase of $5.2 million or 12.5%. Noninterest income was $46.5 million for the three months ended March 31, 2026, compared with $42.8 million for the three months ended December 31, 2025, an increase of $3.7 million or 8.6%. The change for both periods was primarily due to the Mergers.

Noninterest expense was $217.3 million for the three months ended March 31, 2026, compared with $140.3 million for the same period in 2025, an increase of $77.0 million. Noninterest expense was $217.3 million for the three months ended March 31, 2026, compared with $138.7 million for the three months ended December 31, 2025, an increase of $78.6 million. The change for both periods was primarily due to an increase in merger related expenses of $42.5 million, an increase in salaries and benefits and an increase in additional expenses related to three months of American operations and two months of Southwest operations.

Balance Sheet Information

Prosperity had $43.619 billion in total assets at March 31, 2026, an increase of $4.855 billion or 12.5%, compared with $38.765 billion at March 31, 2025. Linked quarter total assets increased by $5.156 billion or 13.4% compared with $38.463 billion at December 31, 2025. Total assets increased primarily due to the Mergers.

Loans were $25.288 billion at March 31, 2026, an increase of $3.310 billion or 15.1% from $21.978 billion at March 31, 2025. Linked quarter loans increased $3.483 billion or 16.0% from $21.805 billion at December 31, 2025. Loans increased primarily due to the Mergers. Loans, excluding Warehouse Purchase Program loans, were $23.855 billion at March 31, 2026, compared with $20.920 billion at March 31, 2025, an increase of $2.935 billion or 14.0%, and compared with $20.501 billion at December 31, 2025, an increase of $3.354 billion or 16.4%.

Deposits were $32.633 billion at March 31, 2026, an increase of $4.606 billion or 16.4%, from $28.027 billion at March 31, 2025. Linked quarter deposits increased $4.150 billion or 14.6% from $28.482 billion at December 31, 2025. Deposits increased primarily due to the Mergers.

Asset Quality

Nonperforming assets totaled $122.1 million or 0.33% of quarterly average interest-earning assets at March 31, 2026, compared with $81.4 million or 0.24% of quarterly average interest-earning assets at March 31, 2025 and $150.8 million or 0.46% of quarterly average interest-earning assets at December 31, 2025.

The allowance for credit losses on loans and off-balance sheet credit exposures was $421.5 million at March 31, 2026, compared with $386.7 million at March 31, 2025 and $371.4 million at December 31, 2025. There was no provision for credit losses for the three months ended March 31, 2026, March 31, 2025 and December 31, 2025.

The allowance for credit losses on loans was $383.8 million or 1.52% of total loans at March 31, 2026, compared with $349.1 million or 1.59% of total loans at March 31, 2025 and $333.7 million or 1.53% of total loans at December 31, 2025. The allowance for credit losses on loans increased during the first quarter of 2026 due to the Mergers, of which $47.5 million was attributable to the American Merger and $43.9 million was attributable to the Southwest Merger. Excluding Warehouse Purchase Program loans, the allowance for credit losses on loans to total loans was 1.61% (1) at March 31, 2026, compared with 1.67% (1) at March 31, 2025 and 1.63% (1) at December 31, 2025.

Net charge-offs were $41.3 million for the three months ended March 31, 2026, compared with net charge-offs of $2.7 million for the three months ended March 31, 2025 and net charge-offs of $5.9 million for the three months ended December 31, 2025. Net charge-offs for the first quarter 2026 included a $33.8 million increase in net charge-offs for commercial and industrial loans. Net charge-offs for the first quarter of 2026 included $2.0 million related to resolved purchased credit deteriorated ("PCD") loans, which had specific reserves that were allocated to the charge-offs. Additionally, reserves on PCD loans increased by $49.0 million due to Day One accounting for PCD loans at the time of the Mergers. Further, $2.0 million of reserves on resolved PCD loans without any related charge-offs were released to the general reserve.

Dividend

Prosperity Bancshares declared a second quarter 2026 cash dividend of $0.60 per share to be paid on July 1, 2026, to all shareholders of record as of June 15, 2026.

Stock Repurchase Program

On January 26, 2026, Prosperity Bancshares announced a stock repurchase program under which up to 5%, or approximately 4.87 million shares, of its outstanding common stock may be acquired over a one-year period expiring on January 26, 2027, at the discretion of management. Under its 2026 stock repurchase program, Prosperity Bancshares repurchased approximately 837,000 shares of its common stock at an average weighted price of $68.15 per share for a total of $57.1 million during the three months ended March 31, 2026.

Pending Acquisition of Stellar Bancorp, Inc.

On January 28, 2026, Prosperity Bancshares and Stellar Bancorp, Inc. ("Stellar") jointly announced the signing of an Agreement and Plan of Merger (the "Merger Agreement"), which provides that Stellar, the parent company of Stellar Bank ("Stellar Bank"), will merge with and into Prosperity Bancshares, and Stellar Bank will merge with and into Prosperity Bank. Stellar Bank operates 52 banking offices in greater Houston and Beaumont, Texas and surrounding areas.

Under the terms and subject to the conditions of the Merger Agreement, Prosperity Bancshares will issue 0.3803 shares of its common stock and $11.36 in cash for each outstanding share of Stellar common stock. Based on Prosperity Bancshares' closing price of $72.90 on January 27, 2026, the total consideration was valued at approximately $2.002 billion. Prosperity has received all necessary regulatory approvals for the acquisition of Stellar and Stellar Bank, and the transaction 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 for in the Merger Agreement.

Acquisition of Southwest Bancshares, Inc.

On February 1, 2026, Prosperity completed the acquisition of Southwest and its wholly owned subsidiary Texas Partners, headquartered in San Antonio, Texas. Texas Partners operated 11 banking offices in Central Texas including its main office in San Antonio, and banking offices in the San Antonio area, Austin and the Hill Country.

Pursuant to the terms of the definitive agreement, Prosperity Bancshares issued 4,094,974 shares of its common stock for all outstanding shares of Southwest common stock in the first quarter of 2026. This resulted in goodwill of $134.1 million as of March 31, 2026, which does not include all the subsequent fair value adjustments that have not yet been finalized. Additionally, Prosperity recognized $33.8 million of core deposit intangibles as of March 31, 2026.

Acquisition of American Bank Holding Corporation

On January 1, 2026, Prosperity completed the acquisition of American and its wholly owned subsidiary American Bank, headquartered in Corpus Christi, Texas. American Bank operated 18 banking offices and two loan production offices in South and Central Texas including its main office in Corpus Christi, and banking offices in San Antonio, Austin, Victoria and the greater Corpus Christi area including Port Aransas and Rockport and a loan production office in Houston, Texas.

Pursuant to the terms of the definitive agreement, Prosperity Bancshares issued 4,439,938 shares of its common stock for all outstanding shares of American common stock in the first quarter of 2026. This resulted in goodwill of $185.0 million as of March 31, 2026, which does not include all the subsequent fair value adjustments that have not yet been finalized. Additionally, Prosperity recognized $31.1 million of core deposit intangibles as of March 31, 2026.

Conference Call

Prosperity's management team will host a conference call on Wednesday, April 29, 2026, at 11:30 a.m. Eastern Time (10:30 a.m. Central Time) to discuss Prosperity's first quarter 2026 earnings. Individuals and investment professionals may participate in the call by dialing 877-883-0383 for domestic participants, or 412-902-6506 for international participants. The participant elite entry number is 7638209.

Alternatively, individuals may listen to the live webcast of the presentation by visiting Prosperity's website at www.prosperitybankusa.com. The webcast may be accessed from Prosperity's Investor Relations page by selecting "Presentations, Webcasts & Calls" from the menu and following the instructions.

Non-GAAP Financial Measures

Prosperity's management uses certain non-GAAP financial measures to evaluate its performance. Specifically, for internal planning and forecasting purposes, Prosperity reviews each of diluted earnings per share, return on average assets, return on average common equity, and return on average tangible common equity, in each case excluding merger related expenses, net of tax, and FDIC special assessment, net of tax; return on average tangible common equity; tangible book value per share; the tangible equity to tangible assets ratio; allowance for credit losses to total loans excluding Warehouse Purchase Program loans; the efficiency ratio, excluding net gains and losses on the sale, write-down or write-up of assets; and the efficiency ratio, excluding net gains and losses on the sale, write-down or write-up of assets, merger related expenses, and FDIC special assessment. Prosperity believes these non-GAAP financial measures provide information useful to investors in understanding Prosperity's financial results and their presentation, together with the accompanying reconciliations, provide a more complete understanding of factors and trends affecting Prosperity's business and allow investors to view performance in a manner similar to management, the entire financial services sector, bank stock analysts and bank regulators. Further, Prosperity believes that these non-GAAP financial measures provide useful information by excluding certain items that may not be indicative of its core operating earnings and business outlook. These non-GAAP financial measures should not be considered a substitute for, nor of greater importance than, GAAP basis financial measures and results; Prosperity strongly encourages investors to review its consolidated financial statements in their entirety and not to rely on any single financial measure. Because non-GAAP financial measures are not standardized, it may not be possible to compare these financial measures with other companies' non-GAAP financial measures having the same or similar names. Please refer to the "Notes to Selected Financial Data" at the end of this Earnings Release for a reconciliation of these non-GAAP financial measures to the nearest respective GAAP financial measures.

Prosperity Bancshares, Inc. ®

As of March 31, 2026, Prosperity Bancshares, Inc. ® is a $43.619 billion Houston, Texas based regional financial holding company providing personal banking services and investments to consumers and businesses throughout Texas and Oklahoma. Founded in 1983, Prosperity believes in a community banking philosophy, taking care of customers, businesses and communities in the areas it serves by providing financial solutions to simplify everyday financial needs. In addition to offering traditional deposit and loan products, Prosperity offers digital banking solutions, credit and debit cards, mortgage services, retail brokerage services, trust and wealth management, and treasury management.

Prosperity currently operates 312 full-service banking locations: 62 in the Houston area, including The Woodlands; 36 in the South Texas area including Corpus Christi and Victoria; 61 in the Dallas/Fort Worth area; 22 in the East Texas area; 28 in the Central Texas area including Austin and San Antonio; 45 in the West Texas area including Lubbock, Midland-Odessa, Abilene; Amarillo and Wichita Falls; 15 in the Bryan/College Station area, 6 in the Central Oklahoma area; 8 in the Tulsa, Oklahoma area; 18 in the Central, South Texas and San Antonio areas doing business as American Bank and 11 in the San Antonio area doing business as Texas Partners Bank.

Cautionary Notes on Forward-Looking Statements

"Safe Harbor" Statement under the Private Securities Litigation Reform Act of 1995: This press release contains, and the remarks by Prosperity's management on the conference call may contain, statements regarding the proposed transaction between Prosperity Bancshares, Inc. ("Prosperity") and Stellar Bancorp, Inc. ("Stellar"); future financial and operating results; benefits and synergies of the proposed transaction; future opportunities for Prosperity; the issuance of common stock of Prosperity contemplated by the Agreement and Plan of Merger by and between Prosperity and Stellar (the "Merger Agreement"); the expected timing of the closing of the proposed transaction contemplated by the Merger Agreement; the ability of the parties to complete the proposed transaction considering the various closing conditions and any other statements about future expectations that constitute forward-looking statements within the meaning of the federal securities laws, including the meaning of the Private Securities Litigation Reform Act of 1995, as amended, Section 27A of the Securities Act of 1933, as amended (the "Securities Act"), and Section 21E of the Securities Exchange Act of 1934, as amended. From time to time, oral or written forward-looking statements may also be included in other information released to the public. Such forward-looking statements are typically, but not exclusively, identified by the use in the statements of words or phrases such as "aim," "anticipate," "believe," "estimate," "expect," "goal," "guidance," "intend," "is anticipated," "is expected," "is intended," "objective," "plan," "projected," "projection," "will affect," "will be," "will continue," "will decrease," "will grow," "will impact," "will increase," "will incur," "will reduce," "will remain," "will result," "would be," variations of such words or phrases (including where the word "could," "may," or "would" is used rather than the word "will" in a phrase) and similar words and phrases indicating that the statement addresses some future result, occurrence, plan or objective. Forward-looking statements include all statements other than statements of historical fact, including forecasts or trends, and are based on current expectations, assumptions, estimates, and projections about Prosperity, Stellar and their respective subsidiaries or related to the proposed transaction between Prosperity and Stellar and are subject to significant risks and uncertainties that could cause actual results to differ materially from the results expressed in such statements.

These forward-looking statements may include information about Prosperity's and Stellar's possible or assumed future economic performance or future results of operations, including future revenues, income, expenses, provision for loan losses, provision for taxes, effective tax rate, earnings per share and cash flows and Prosperity's and Stellar's future capital expenditures and dividends, future financial condition and changes therein, including changes in Prosperity's and Stellar's loan portfolio and allowance for loan losses, future capital structure or changes therein, as well as the plans and objectives of management for Prosperity's and Stellar's future operations, future or proposed acquisitions, the future or expected effect of acquisitions on Prosperity's and Stellar's operations, results of operations, financial condition, and future economic performance, statements about the anticipated benefits of the proposed transaction, and statements about the assumptions underlying any such statement.

These forward-looking statements are not guarantees of future performance and are based on expectations and assumptions Prosperity currently believes to be valid. Because forward-looking statements relate to future results and occurrences, many of which are outside of the control of Prosperity and Stellar, they are subject to inherent uncertainties, risks and changes in circumstances that are difficult to predict. These risks and uncertainties include, but are not limited to, whether Prosperity can: successfully identify acquisition targets and integrate the businesses of acquired companies and banks; continue to sustain its current internal growth rate or total growth rate; provide products and services that appeal to its customers; continue to have access to debt and equity capital markets; and achieve its sales objectives. Other risks include, but are not limited to: the possibility that credit quality could deteriorate; actions of competitors; changes in laws and regulations (including changes in governmental interpretations of regulations and changes in accounting standards); a deterioration or downgrade in the credit quality and credit agency ratings of the securities in Prosperity's securities portfolio; customer and consumer demand, including customer and consumer response to marketing; effectiveness of spending, investments or programs; fluctuations in the cost and availability of supply chain resources; economic conditions, including currency rate, interest rate and commodity price fluctuations; changes in trade policies by the United States or other countries, such as tariffs or retaliatory tariffs; and the effect, impact, potential duration or other implications of weather and climate-related events. Many possible events or factors could adversely affect the future financial results and performance of Prosperity, Stellar or the combined company and could cause those results or performance to differ materially from those expressed in or implied by the forward-looking statements. Such risks and uncertainties include, among others: (1) the risk that the cost savings and synergies from the proposed transaction may not be fully realized or may take longer than anticipated to be realized, (2) disruption to Prosperity's and Stellar's businesses as a result of the announcements and pendency of the proposed transaction, (3) the risk that the integration of Stellar's businesses and operations into Prosperity will be materially delayed or will be more costly or difficult than expected, or that Prosperity is otherwise unable to successfully integrate Stellar's business into its own, including as a result of unexpected factors or events, (4) the failure to obtain the necessary approval by the shareholders of Stellar, (5) reputational risk and the reaction of each company's customers, suppliers, employees or other business partners to the proposed transaction, (6) the failure of the closing conditions in the Merger Agreement to be satisfied, or any unexpected delay in closing the proposed transaction or the occurrence of any event, change or other circumstances that could give rise to the termination of the Merger Agreement, (7) the dilution caused by the issuances of additional shares of Prosperity's common stock in the proposed transaction, (8) the possibility that the proposed transaction may be more expensive to complete than anticipated, including as a result of unexpected factors or events, (9) the outcome of any legal or regulatory proceedings that may be currently pending or later instituted against Prosperity before or after the proposed transaction, or against Stellar, (10) diversion of management's attention from ongoing business operations and (11) general competitive, economic, political and market conditions and other factors that may affect future results of Prosperity and Stellar. Prosperity and Stellar disclaim any obligation to update such factors or to publicly announce the results of any revisions to any of the forward-looking statements included herein to reflect future events or developments. These and various other risks, uncertainties, assumptions, and factors are discussed in the respective Annual Reports on Form 10-K for the year ended December 31, 2025, Quarterly Reports on Form 10-Q, and Current Reports on Form 8-K, filed by Prosperity or Stellar and in other filings made by Prosperity and Stellar with the Securities and Exchange Commission (the "SEC") from time to time.

Additional Information about the Transaction and Where to Find It

In connection with the proposed transaction, Prosperity has filed with the SEC a registration statement (the "Registration Statement") on Form S-4 (File No. 333-294882) to register the shares of Prosperity common stock to be issued to the shareholders of Stellar in connection with the proposed transaction. The Registration Statement includes a prospectus of Prosperity and a proxy statement of Stellar (the "proxy statement/prospectus"), which has been sent to the shareholders of Stellar in connection with the proposed transaction. The Registration Statement was declared effective on April 21, 2026, at which time Prosperity filed a final prospectus and Stellar filed a definitive proxy statement. The mailing of the proxy statement/prospectus to Stellar shareholders commenced on April 23, 2026. This communication is not a substitute for the Registration Statement, the proxy statement/prospectus or any other document that may be filed by Prosperity or Stellar with the SEC. INVESTORS AND SECURITY HOLDERS ARE URGED TO READ THE REGISTRATION STATEMENT, THE PROXY STATEMENT/PROSPECTUS INCLUDED WITHIN THE REGISTRATION STATEMENT AND ANY OTHER RELEVANT DOCUMENTS FILED WITH THE SEC IN CONNECTION WITH THE PROPOSED TRANSACTION OR INCORPORATED BY REFERENCE INTO THE PROXY/STATEMENT PROSPECTUS, AS WELL AS ANY AMENDMENTS OR SUPPLEMENTS TO THESE DOCUMENTS, CAREFULLY AND IN THEIR ENTIRETY, BECAUSE THEY CONTAIN OR WILL CONTAIN IMPORTANT INFORMATION. Investors and security holders may obtain the Registration Statement and the proxy statement/prospectus and other documents that are filed with the SEC by Prosperity or Stellar, as applicable, free of charge from the SEC's website at https://www.sec.gov or through the investor relations section of Prosperity's website at https://www.prosperitybankusa.com/investor-relations/ or Stellar's website at https://ir.stellar.bank.

Participants in the Solicitation

Prosperity, Stellar and certain of their directors and executive officers and other employees may be deemed to be participants in the solicitation of proxies from Stellar's shareholders in connection with the proposed transaction. Information about the directors and executive officers of Prosperity and their ownership of Prosperity common stock is contained in the definitive proxy statement for Prosperity's 2026 annual meeting of shareholders (the "Prosperity Annual Meeting Proxy Statement"), which was filed with the SEC on March 16, 2026, including under the headings "Item 1. Election of Directors," "Corporate Governance," "Executive Compensation and Other Matters," "Item 3. Advisory Vote on Executive Compensation," and "Beneficial Ownership of Common Stock by Management of the Company and Principal Shareholders." Information about the directors and executive officers of Stellar and their ownership of Stellar common stock is contained in Amendment No. 1 to the Annual Report on Form 10-K for the year ended December 31, 2025 of Stellar (the "Stellar 10-K/A"), which was filed with the SEC on April 17, 2026. Additional information regarding the persons who may, under the rules of the SEC, be deemed participants in the solicitation of the shareholders of Stellar in connection with the proposed transaction, including a description of their direct or indirect interests, by security holdings or otherwise, is included in the proxy statement/prospectus relating to the proposed transaction filed with the SEC. To the extent holdings of securities by potential participants (or the identity of such participants) have changed since the information printed in the Prosperity Annual Meeting Proxy Statement or the Stellar 10-K/A, such information has been or will be reflected on Statements of Change in Ownership on Forms 3 and 4 filed with the SEC, as applicable. Free copies of the proxy statement/prospectus relating to the proposed transaction and free copies of the other SEC filings to which reference is made in this paragraph may be obtained from the SEC's website at https://www.sec.gov or through the investor relations section of Prosperity's website at https://www.prosperitybankusa.com/investor-relations/ or Stellar's website at https://ir.stellar.bank.

No Offer or Solicitation

This communication is for informational purposes only and is not intended to and does not constitute an offer to subscribe for, buy or sell, or the solicitation of an offer to subscribe for, buy or sell, or an invitation to subscribe for, buy or sell any securities or a solicitation of any vote or approval in any jurisdiction, nor shall there be any sale, issuance or transfer of securities in any jurisdiction in which such offer, invitation, sale or solicitation would be unlawful prior to registration or qualification under the securities laws of any such jurisdiction. No offer of securities shall be made except by means of a prospectus meeting the requirements of Section 10 of the Securities Act, and otherwise in accordance with applicable law.

(1)

Refer to the "Notes to Selected Financial Data" at the end of this Earnings Release for a reconciliation of this non-GAAP financial measure to the nearest GAAP financial measure.

(2)

Includes purchase accounting adjustments of $4.8 million, net of tax, primarily comprised of loan discount accretion of $3.7 million and merger related provision for credit losses of $42.5 million for the three months ended March 31, 2026.

(3)

Includes purchase accounting adjustments of $3.2 million, net of tax, primarily comprised of loan discount accretion of $3.3 million for the three months ended March 31, 2025.

(4)

Includes purchase accounting adjustments of $2.7 million, net of tax, primarily comprised of loan discount accretion of $3.1 million for the three months ended December 31, 2025.

Prosperity Bancshares, Inc. ®

Financial Highlights (Unaudited)

(In thousands)

Mar 31, 2026

Dec 31, 2025

Sep 30, 2025

Jun 30, 2025

Mar 31, 2025

Balance Sheet Data (at period end)

Loans held for sale

21,925

14,155

11,297

6,004

9,764

Loans held for investment

23,832,909

20,486,415

20,738,294

20,903,944

20,909,913

Loans held for investment - Warehouse Purchase

Program

1,433,152

1,304,798

1,278,178

1,287,440

1,057,893

Total loans

25,287,986

21,805,368

22,027,769

22,197,388

21,977,570

Investment securities (A)

11,951,591

10,613,425

10,232,462

10,608,104

10,792,731

Federal funds sold

209

217

210

197

221

Allowance for credit losses on loans

(383,840)

(333,742)

(339,626)

(346,084)

(349,101)

Cash and due from banks

1,547,967

1,747,511

1,766,115

1,304,993

1,694,637

Goodwill

3,822,283

3,503,127

Core deposit intangibles, net

111,243

51,605

55,194

58,796

62,406

Other real estate owned

13,257

13,296

13,750

7,874

8,012

Fixed assets, net

429,775

383,449

378,776

374,602

373,273

Other assets

838,712

679,169

692,692

708,355

701,799

Total assets

43,619,183

38,463,425

38,330,469

38,417,352

38,764,675

Noninterest-bearing deposits

10,580,920

9,467,911

9,522,028

9,426,657

9,675,915

Interest-bearing deposits

22,051,836

19,014,573

18,260,066

18,046,754

18,350,884

Total deposits

32,632,756

28,482,484

27,782,094

27,473,411

28,026,799

Other borrowings

2,200,000

1,950,000

2,400,000

2,900,000

2,700,000

Securities sold under repurchase agreements

176,099

201,216

185,797

183,572

216,086

Subordinated notes and junior subordinated debentures

76,186

—

Allowance for credit losses on off-balance sheet credit

exposures

37,646

Other liabilities

288,645

175,939

259,994

222,987

267,083

Total liabilities

35,411,332

30,847,285

30,665,531

30,817,616

31,247,614

Shareholders' equity (B)

8,207,851

7,616,140

7,664,938

7,599,736

7,517,061

Total liabilities and equity

43,619,183

38,463,425

38,330,469

38,417,352

38,764,675

(A)

Includes $44, ($375), ($1,987), ($1,657) and ($1,374) in unrealized gain (losses) on available for sale securities for the quarterly periods ended March 31, 2026, December 31, 2025, September 30, 2025, June 30, 2025, and March 31, 2025, respectively.

(B)

Includes $35, ($296), ($1,570), ($1,309) and ($1,085) in after-tax unrealized gain (losses) on available for sale securities for the quarterly periods ended March 31, 2026, December 31, 2025, September 30, 2025, June 30, 2025, and March 31, 2025, respectively.

Prosperity Bancshares, Inc. ®

Financial Highlights (Unaudited)

(In thousands)

Three Months Ended

Mar 31,

2026

Dec 31,

2025

Sep 30,

2025

Jun 30,

2025

Mar 31,

2025

Income Statement Data

Interest income:

Loans

361,756

321,516

329,445

325,490

319,023

Securities (C)

70,531

56,767

58,207

57,836

57,886

Federal funds sold and other earning assets

9,488

8,364

10,455

9,438

15,896

Total interest income

441,775

386,647

398,107

392,764

392,805

Interest expense:

Deposits

104,237

94,625

95,965

93,790

95,597

Other borrowings

14,783

16,028

27,613

30,101

30,492

Securities sold under repurchase agreements

902

1,041

1,094

1,151

1,334

Subordinated notes and junior subordinated

debentures

703

—

Total interest expense

120,625

111,694

124,672

125,042

127,423

Net interest income

321,150

274,953

273,435

267,722

265,382

Provision for credit losses

—

Net interest income after provision for credit losses

321,150

274,953

273,435

267,722

265,382

Noninterest income:

Nonsufficient funds (NSF) fees

10,867

9,715

9,805

8,885

9,147

Credit card, debit card and ATM card income

9,483

9,462

9,446

9,761

8,739

Service charges on deposit accounts

8,680

7,618

7,317

7,645

7,408

Trust income

4,922

3,662

3,526

3,859

3,601

Mortgage income

1,280

954

931

965

1,009

Brokerage income

1,568

1,570

1,328

1,225

1,262

Bank owned life insurance income

2,598

2,117

2,111

1,985

2,115

Net gain (loss) on sale or write-down of assets

318

1,414

(235)

Other noninterest income

6,758

7,647

6,771

7,243

8,255

Total noninterest income

46,474

42,780

41,238

42,982

41,301

Noninterest expense:

Salaries and benefits

109,211

88,384

87,949

87,296

89,476

Net occupancy and equipment

10,654

9,379

9,395

9,168

9,146

Credit and debit card, data processing and software

amortization

18,114

12,621

12,515

12,056

11,422

Regulatory assessments and FDIC insurance

6,041

1,600

5,198

5,508

5,789

Core deposit intangibles amortization

5,259

3,588

3,602

3,610

3,641

Depreciation

5,548

5,155

4,966

4,779

4,774

Communications

3,834

3,528

3,480

3,507

3,473

Other real estate expense

341

219

314

204

140

Net (gain) loss on sale or write-down of other real

estate

(41)

109

(81)

(222)

(30)

Merger related expenses

42,516

268

—

Other noninterest expense

15,810

13,861

11,235

12,659

12,470

Total noninterest expense

217,287

138,712

138,635

138,565

140,301

Income before income taxes

150,337

179,021

176,038

172,139

166,382

Provision for income taxes

34,070

39,114

38,482

36,984

36,157

Net income available to common shareholders

116,267

139,907

137,556

135,155

130,225

(C)

Interest income on securities was reduced by net premium amortization of $3,829, $4,668, $2,877, $4,926, and $5,027 for the three months ended March 31, 2026, December 31, 2025, September 30, 2025, June 30, 2025, and March 31, 2025, respectively.

Prosperity Bancshares, Inc. ®

Financial Highlights (Unaudited)

(Dollars and share amounts in thousands, except per share data and market prices)

Three Months Ended

Mar 31,

2026

Dec 31,

2025

Sep 30,

2025

Jun 30,

2025

Mar 31,

2025

Profitability

Net income (D) (E)

116,267

139,907

137,556

135,155

130,225

Basic earnings per share

1.16

1.49

1.45

1.42

1.37

Diluted earnings per share

1.16

1.49

1.45

1.42

1.37

Return on average assets (F) (J)

1.10

1.49

1.44

1.41

1.34

Return on average common equity (F) (J)

5.70

7.30

7.18

7.13

6.94

Return on average tangible common equity (F) (G) (J)

10.59

13.61

13.43

13.44

13.23

Tax equivalent net interest margin (D) (E) (H)

3.51

3.30

3.24

3.18

3.14

Efficiency ratio (G) (I) (K)

59.16

43.66

44.06

44.80

45.71

Liquidity and Capital Ratios

Equity to assets

18.82

19.80

20.00

19.78

19.39

Common equity tier 1 capital

15.44

17.55

17.53

17.10

16.92

Tier 1 risk-based capital

15.44

17.55

17.53

17.10

16.92

Total risk-based capital

16.69

18.80

18.78

18.35

18.17

Tier 1 leverage capital

11.22

11.93

11.90

11.62

11.20

Period end tangible equity to period end tangible assets

(G)

10.77

11.63

11.81

11.58

11.23

Other Data

Weighted-average shares used in computing earnings

per common share

Basic

99,825

94,044

95,093

95,277

95,266

Diluted

99,825

94,044

95,093

95,277

95,266

Period end shares outstanding

100,835

93,058

94,993

95,277

95,258

Cash dividends paid per common share

0.60

0.58

Book value per common share

81.40

81.84

80.69

79.76

78.91

Tangible book value per common share (G)

42.39

43.64

43.23

42.38

41.48

Common Stock Market Price

High

77.20

73.90

75.44

74.56

82.75

Low

63.20

61.07

64.27

61.57

68.96

Period end closing price

67.18

69.11

66.35

70.24

71.37

Employees – FTE (excluding overtime)

4,429

3,941

3,937

3,921

3,898

Number of banking centers

312

283

284

(D)

Includes purchase accounting adjustments for the periods presented as follows:

Three Months Ended

Mar 31,

2026

Dec 31,

2025

Sep 30,

2025

Jun 30,

2025

Mar 31,

2025

Loan discount accretion

Purchased seasoned loans ("PS loans")

$2,562

$2,926

$2,242

$2,486

$2,615

PCD

$1,186

$205

$613

$638

$677

Securities net accretion

$1,573

$342

$1,475

$409

$705

Time deposits amortization

$(699)

$(1)

$(2)

$(9)

(E)

Using effective tax rate of 22.7%, 21.8%, 21.9%, 21.5% and 21.7% for the three months ended March 31, 2026, December 31, 2025, September 30, 2025, June 30, 2025 and March 31, 2025, respectively.

(F)

Interim periods annualized.

(G)

Refer to the "Notes to Selected Financial Data" at the end of this Earnings Release for a reconciliation of this non-GAAP financial measure to the nearest GAAP financial measure.

(H)

Net interest margin for all periods presented is based on average balances on an actual 365-day basis.

(I)

Calculated by dividing total noninterest expense, excluding credit loss provisions, by net interest income plus noninterest income, excluding net gains and losses on the sale, write-down or write-up of assets and securities. Additionally, taxes are not part of this calculation.

(J)

For calculations of the annualized returns on average assets, average common equity and average tangible common equity excluding merger related expenses, net of tax, and FDIC special assessment, net of tax, refer to the "Notes to Selected Financial Data" at the end of this Earnings Release for a reconciliation of this non-GAAP financial measure to the nearest GAAP financial measure.

(K)

For calculations of the efficiency ratio excluding merger related expenses and FDIC special assessment refer to the "Notes to Selected Financial Data" at the end of this Earnings Release for a reconciliation of these non-GAAP financial measures to the nearest respective GAAP financial measures.

Prosperity Bancshares, Inc. ®

Financial Highlights (Unaudited)

(Dollars in thousands)

YIELD ANALYSIS

Three Months Ended

Mar 31, 2026

Dec 31, 2025

Mar 31, 2025

Average

Balance

Interest

Earned/

Interest

Paid

Average

Yield/

Rate

(L)

Average

Balance

Interest

Earned/

Interest

Paid

Average

Yield/

Rate

(L)

Average

Balance

Interest

Earned/

Interest

Paid

Average

Yield/

Rate

(L)

Interest-earning assets:

Loans held for sale

15,800

238

6.11 %

11,077

175

6.27 %

7,570

127

6.80 %

Loans held for investment

23,469,020

344,596

5.95 %

20,603,235

302,679

5.83 %

20,959,226

305,068

5.90 %

Loans held for investment -

Warehouse Purchase Program

1,207,793

16,922

5.68 %

1,258,036

18,662

5.89 %

876,086

13,828

6.40 %

Total loans

24,692,613

361,756

5.94 %

21,872,348

321,516

5.83 %

21,842,882

319,023

5.92 %

Investment securities

11,469,762

70,531

2.49 %

(M)

10,378,696

56,767

2.17 %

(M)

11,017,400

57,886

2.13 %

(M)

Federal funds sold and other

earning assets

1,026,015

9,488

3.75 %

830,926

8,364

3.99 %

1,443,220

15,896

4.47 %

Total interest-earning assets

37,188,390

441,775

4.82 %

33,081,970

386,647

4.64 %

34,303,502

392,805

4.64 %

Allowance for credit losses on

loans

(330,133)

(337,892)

(350,715)

Noninterest-earning assets

5,361,351

4,921,850

5,004,291

Total assets

42,219,608

37,665,928

38,957,078

Interest-bearing liabilities:

Interest-bearing demand deposits

6,266,423

13,993

0.91 %

4,812,342

9,088

0.75 %

5,224,796

9,019

0.70 %

Savings and money market

deposits

10,583,184

50,719

1.94 %

9,054,281

44,771

1.96 %

9,007,286

45,645

2.06 %

Certificates and other time

deposits

4,830,369

39,525

3.32 %

4,519,742

40,766

3.58 %

4,426,521

40,933

3.75 %

Other borrowings

1,620,556

14,783

3.70 %

1,595,652

16,028

3.99 %

2,776,667

30,492

4.45 %

Securities sold under repurchase

agreements

177,719

902

2.06 %

185,289

1,041

2.23 %

217,945

1,334

2.48 %

Subordinated notes and junior

subordinated debentures

63,673

703

4.48 %

—

Total interest-bearing liabilities

23,541,924

120,625

2.08 %

(N)

20,167,306

111,694

2.20 %

(N)

21,653,215

127,423

2.39 %

(N)

Noninterest-bearing liabilities:

Noninterest-bearing demand

deposits

10,260,022

9,543,581

9,504,540

Allowance for credit losses on off-

balance sheet credit exposures

38,070

37,646

Other liabilities

218,810

248,593

255,876

Total liabilities

34,058,826

29,997,126

31,451,277

Shareholders' equity

8,160,782

7,668,802

7,505,801

Total liabilities and shareholders' equity

42,219,608

37,665,928

38,957,078

Net interest income and margin

321,150

3.50 %

274,953

3.30 %

265,382

3.14 %

Non-GAAP to GAAP

reconciliation:

Tax equivalent adjustment

575

514

587

Net interest income and margin

(tax equivalent basis)

321,725

3.51 %

275,467

3.30 %

265,969

3.14 %

(L)

Annualized and based on an actual 365-day basis.

(M)

Yield on securities was impacted by net premium amortization of $3,829, $4,668, and $5,027 for the three months ended March 31, 2026, December 31, 2025, and March 31, 2025, respectively.

(N)

Total cost of funds, including noninterest bearing deposits, was 1.45%, 1.49% and 1.66% for the three months ended March 31, 2026, December 31, 2025, and March 31, 2025, respectively.

Prosperity Bancshares, Inc. ®

Financial Highlights (Unaudited)

(Dollars in thousands)

Three Months Ended

Mar 31, 2026

Dec 31, 2025

Sep 30, 2025

Jun 30, 2025

Mar 31, 2025

YIELD TREND (O)

Interest-Earning Assets:

Loans held for sale

6.11

6.27

6.64

6.79

6.80

Loans held for investment

5.95

5.83

5.90

5.88

5.90

Loans held for investment - Warehouse Purchase

Program

5.68

5.89

6.31

6.34

6.40

Total loans

5.94

5.83

5.92

5.91

5.92

Investment securities (P)

2.49

2.17

2.19

2.13

Federal funds sold and other earning assets

3.75

3.99

4.44

4.50

4.47

Total interest-earning assets

4.82

4.64

4.71

4.66

4.64

Interest-Bearing Liabilities:

Interest-bearing demand deposits

0.91

0.75

0.76

0.74

0.70

Savings and money market deposits

1.94

1.96

2.07

2.05

2.06

Certificates and other time deposits

3.32

3.58

3.60

3.59

3.75

Other borrowings

3.70

3.99

4.42

4.44

4.45

Securities sold under repurchase agreements

2.06

2.23

2.32

2.37

2.48

Subordinated notes and junior subordinated

debentures

4.48

—

Total interest-bearing liabilities

2.08

2.20

2.39

2.38

2.39

Net Interest Margin

3.50

3.30

3.23

3.18

3.14

Net Interest Margin (tax equivalent)

3.51

3.30

3.24

3.18

3.14

(O)

Annualized and based on average balances on an actual 365-day basis.

(P)

Yield on securities was impacted by net premium amortization of $3,829, $4,668, $2,877, $4,926 and $5,027 for the three months ended March 31, 2026, December 31, 2025, September 30, 2025, June 30, 2025, and March 31, 2025, respectively.

Prosperity Bancshares, Inc. ®

Financial Highlights (Unaudited)

(Dollars in thousands)

Three Months Ended

Mar 31, 2026

Dec 31, 2025

Sep 30, 2025

Jun 30, 2025

Mar 31, 2025

Balance Sheet Averages

Loans held for sale

15,800

11,077

8,371

9,813

7,570

Loans held for investment

23,469,020

20,603,235

20,851,896

20,907,400

20,959,226

Loans held for investment - Warehouse Purchase

Program

1,207,793

1,258,036

1,217,579

1,179,307

876,086

Total loans

24,692,613

21,872,348

22,077,846

22,096,520

21,842,882

Investment securities

11,469,762

10,378,696

10,530,807

10,867,856

11,017,400

Federal funds sold and other earning assets

1,026,015

830,926

934,318

841,933

1,443,220

Total interest-earning assets

37,188,390

33,081,970

33,542,971

33,806,309

34,303,502

Allowance for credit losses on loans

(330,133)

(337,892)

(343,872)

(348,310)

(350,715)

Cash and due from banks

391,668

311,541

291,809

294,379

326,066

Goodwill

3,718,640

3,503,127

3,503,128

Core deposit intangibles, net

50,089

53,553

56,956

60,739

64,293

Other real estate

14,690

14,004

11,533

8,749

7,105

Fixed assets, net

423,530

380,254

377,680

374,486

374,448

Other assets

762,734

659,371

689,659

691,735

729,251

Total assets

42,219,608

37,665,928

38,129,863

38,391,214

38,957,078

Noninterest-bearing deposits

10,260,022

9,543,581

9,451,153

9,508,845

9,504,540

Interest-bearing demand deposits

6,266,423

4,812,342

4,656,452

4,807,864

5,224,796

Savings and money market deposits

10,583,184

9,054,281

8,977,585

8,944,897

9,007,286

Certificates and other time deposits

4,830,369

4,519,742

4,422,996

4,366,510

4,426,521

Total deposits

31,939,998

27,929,946

27,508,186

27,628,116

28,163,143

Other borrowings

1,620,556

1,595,652

2,480,435

2,717,583

2,776,667

Securities sold under repurchase agreements

177,719

185,289

187,462

194,577

217,945

Subordinated notes and junior subordinated

debentures

63,673

—

Allowance for credit losses on off-balance sheet

credit exposures

38,070

37,646

Other liabilities

218,810

248,593

258,156

227,002

255,876

Shareholders' equity

8,160,782

7,668,802

7,657,978

7,586,290

7,505,801

Total liabilities and equity

42,219,608

37,665,928

38,129,863

38,391,214

38,957,078

Prosperity Bancshares, Inc. ®

Financial Highlights (Unaudited)

(Dollars in thousands)

Mar 31, 2026

Dec 31, 2025

Sep 30, 2025

Jun 30, 2025

Mar 31, 2025

Period End Balances

Loan Portfolio

Commercial and industrial

2,759,190

10.9

1,864,337

8.6

1,879,282

8.5

1,897,117

8.6

1,915,124

8.7

Warehouse purchase

program

1,433,152

5.7

1,304,798

6.0

1,278,178

5.8

1,287,440

5.8

1,057,893

4.8

Construction, land

development and other

land loans

3,253,389

12.9

2,741,455

12.6

2,865,279

13.0

2,873,238

12.9

2,845,082

13.0

1-4 family residential

7,876,021

31.1

7,430,929

34.1

7,461,900

33.9

7,530,816

33.9

7,576,350

34.5

Home equity

846,739

3.3

843,708

3.8

848,740

3.9

869,370

3.9

896,529

4.1

Commercial real estate

(includes multi-family

residential)

7,126,212

28.2

5,776,397

26.5

5,796,937

26.3

5,827,645

26.3

5,783,410

26.3

Agriculture (includes

farmland)

1,064,540

4.2

1,027,904

4.7

1,019,589

4.6

1,029,250

4.6

1,013,960

4.6

Consumer and other

406,680

1.6

376,241

1.7

366,027

1.7

368,747

1.7

378,821

1.7

Energy

522,063

2.1

439,599

2.0

511,837

2.3

513,765

2.3

510,401

2.3

Total loans

25,287,986

21,805,368

22,027,769

22,197,388

21,977,570

Deposit Types

Noninterest-bearing DDA

10,580,920

32.4

9,467,911

33.2

9,522,028

34.3

9,426,657

34.3

9,675,915

34.5

Interest-bearing DDA

6,345,797

19.5

5,365,795

18.8

4,766,146

17.2

4,708,251

17.1

4,931,769

17.6

Money market

8,163,557

25.0

6,538,213

23.0

6,402,591

23.0

6,302,770

23.0

6,339,509

22.6

Savings

2,743,732

8.4

2,592,873

9.1

2,616,196

9.4

2,667,859

9.7

2,703,736

9.7

Certificates and other time deposits

4,798,750

14.7

4,517,692

15.9

4,475,133

16.1

4,367,874

15.9

4,375,870

15.6

Total deposits

32,632,756

28,482,484

27,782,094

27,473,411

28,026,799

Loan to Deposit Ratio

77.5

76.6

79.3

80.8

78.4

Prosperity Bancshares, Inc. ®

Financial Highlights (Unaudited)

(Dollars in thousands)

Construction Loans

Mar 31, 2026

Dec 31, 2025

Sep 30, 2025

Jun 30, 2025

Mar 31, 2025

Single family residential construction

690,393

21.2

613,288

22.4

665,194

23.2

696,569

24.2

727,417

25.6

Land development

407,811

12.5

252,650

9.2

248,616

8.7

227,254

7.9

225,784

7.9

Raw land

276,693

8.5

220,169

8.0

230,021

8.0

248,380

8.7

261,918

9.2

Residential lots

249,071

7.7

199,709

7.3

203,396

7.1

217,835

7.6

219,115

7.7

Commercial lots

61,691

1.9

59,683

2.2

59,853

2.1

55,176

1.9

56,343

2.0

Commercial construction and other

1,567,640

48.2

1,396,850

50.9

1,459,255

50.9

1,428,985

49.7

1,355,587

47.6

Net unaccreted premium (discount)

(894)

(1,056)

(961)

(1,082)

Total construction loans

3,253,389

2,741,455

2,865,279

2,873,238

2,845,082

Non-Owner Occupied Commercial Real Estate Loans by Metropolitan Statistical Area (MSA) as of March 31, 2026

Houston

Dallas

Austin

OK City

Tulsa

Other (Q)

Total

Collateral Type

Shopping center/retail

237,105

218,672

60,763

16,078

10,018

364,143

906,779

Commercial and industrial

buildings

213,914

104,905

31,958

32,429

11,380

301,121

695,707

Office buildings

149,264

292,193

77,325

42,683

4,364

114,900

680,729

Medical buildings

112,178

23,961

25,942

42,033

25,393

74,690

304,197

Apartment buildings

144,493

83,548

101,393

9,566

12,568

224,751

576,319

Hotel

119,709

117,533

36,689

12,740

—

252,738

539,409

Other

192,874

70,247

153,285

4,638

6,663

433,289

860,996

Total

1,169,537

911,059

487,355

160,167

70,386

1,765,632

4,564,136

(R)

Acquired Loans

PS Loans

PCD Loans

Total Acquired Loans

Balance at

Acquisition

Date

Balance at

Dec 31,

2025

Balance at

Mar 31,

2026

Balance at

Acquisition

Date

Balance at

Dec 31,

2025

Balance at

Mar 31,

2026

Balance at

Acquisition

Date

Balance at

Dec 31,

2025

Balance at

Mar 31,

2026

Loan marks:

Acquired banks (S)

388,625

17,479

15,064

332,400

5,267

5,053

721,025

22,746

20,117

American Bank (T)

15,473

—

15,902

1,923

—

1,297

17,396

—

17,199

Texas Partners Bank (U)

38,467

—

37,626

2,422

—

2,090

40,889

—

39,716

Total

442,565

17,479

68,592

336,745

5,267

8,440

779,310

22,746

77,032

Acquired portfolio loan balances:

Acquired banks (S)

14,323,981

1,498,731

1,331,556

1,376,673

300,010

293,365

15,700,654

(V)

1,798,741

1,624,921

American Bank (T)

1,810,982

—

1,684,101

93,300

—

89,055

1,904,282

—

1,773,156

Texas Partners Bank (U)

1,864,565

—

1,769,908

76,199

—

70,248

1,940,764

—

1,840,156

Total

17,999,528

1,498,731

4,785,565

1,546,172

300,010

452,668

19,545,700

1,798,741

5,238,233

Acquired portfolio loan

balances less loan marks

17,556,963

1,481,252

4,716,973

1,209,427

294,743

444,228

18,766,390

1,775,995

5,161,201

(Q)

Includes other MSA and non-MSA regions.

(R)

Represents a portion of total commercial real estate loans of $7.126 billion as of March 31, 2026.

(S)

Includes Bank Arlington, American State Bank, Community National Bank, First Federal Bank Texas, Coppermark Bank, First Victoria National Bank, The F&M Bank & Trust Company, Tradition Bank, LegacyTexas Bank, FirstCapital Bank and Lone Star Bank.

(T)

The American Merger was completed on January 1, 2026. The American Merger resulted in the addition of $1.904 billion in loans with related purchase accounting adjustments of $17.4 million at acquisition date.

(U)

The Southwest Merger was completed on February 1, 2026. The Southwest Merger resulted in the addition of $1.941 billion in loans with related purchase accounting adjustments of $40.9 million at acquisition date.

(V)

Actual principal balances acquired.

Prosperity Bancshares, Inc. ®

Financial Highlights (Unaudited)

(Dollars in thousands)

Three Months Ended

Mar 31,

2026

Dec 31,

2025

Sep 30,

2025

Jun 30,

2025

Mar 31,

2025

Asset Quality

Nonaccrual loans

106,473

137,217

105,529

102,031

73,287

Accruing loans 90 or more days past due

2,241

317

268

576

Total nonperforming loans

108,714

137,534

105,797

102,607

73,378

Repossessed assets

136

Other real estate

13,257

13,296

13,750

7,874

8,012

Total nonperforming assets

122,107

150,842

119,563

110,487

81,419

Nonperforming assets:

Commercial and industrial (includes energy)

17,495

57,237

27,880

27,680

8,966

Construction, land development and other land loans

2,054

2,183

583

1,859

1,952

1-4 family residential (includes home equity)

63,168

60,296

57,241

50,501

42,481

Commercial real estate (includes multi-family residential)

17,880

9,215

11,471

12,865

12,257

Agriculture (includes farmland)

16,259

16,713

17,080

17,547

15,725

Consumer and other

5,251

5,198

5,308

Total

122,107

150,842

119,563

110,487

81,419

Number of loans/properties

484

449

424

392

363

Allowance for credit losses on loans

383,840

333,742

339,626

346,084

349,101

Net charge-offs (recoveries):

Commercial and industrial (includes energy)

39,225

5,388

3,341

1,044

330

Construction, land development and other land loans

—

(154)

(3)

(156)

1-4 family residential (includes home equity)

862

175

853

342

1,051

Commercial real estate (includes multi-family residential)

(121)

(665)

1,015

178

Agriculture (includes farmland)

(5)

(40)

(14)

—

Consumer and other

1,291

1,145

1,255

1,593

1,301

Total

41,309

5,884

6,458

3,017

2,704

Asset Quality Ratios

Nonperforming assets to average interest-earning assets

0.33

0.46

0.36

0.33

0.24

Nonperforming assets to loans and other real estate

0.48

0.69

0.54

0.50

0.37

Net charge-offs to average loans (annualized)

0.67

0.11

0.12

0.05

Allowance for credit losses on loans to total loans

1.52

1.53

1.54

1.56

1.59

Allowance for credit losses on loans to total loans, excluding Warehouse Purchase Program loans (G)

1.61

1.63

1.64

1.66

1.67

Prosperity Bancshares, Inc. ®

Notes to Selected Financial Data (Unaudited)

(Dollars and share amounts in thousands, except per share data)

NOTES TO SELECTED FINANCIAL DATA

Prosperity's management uses certain non-GAAP (generally accepted accounting principles) financial measures to evaluate its performance. Specifically, for internal planning and forecasting purposes, Prosperity reviews each of diluted earnings per share, return on average assets, return on average common equity, and return on average tangible common equity, in each case excluding merger related expenses, net of tax, and FDIC special assessment, net of tax; return on average tangible common equity; tangible book value per share; the tangible equity to tangible assets ratio; allowance for credit losses to total loans excluding Warehouse Purchase Program loans; the efficiency ratio, excluding net gains and losses on the sale, write-down or write-up of assets; and the efficiency ratio, excluding net gains and losses on the sale, write-down or write-up of assets, merger related expenses and FDIC special assessment. In addition, due to the application of purchase accounting, Prosperity uses certain non-GAAP financial measures and ratios that exclude the impact of these items to evaluate its allowance for credit losses to total loans (excluding Warehouse Purchase Program loans). Prosperity has included information below relating to these non-GAAP financial measures for the applicable periods presented.

Three Months Ended

Mar 31,

2026

Dec 31,

2025

Sep 30,

2025

Jun 30,

2025

Mar 31,

2025

Reconciliation of diluted earnings per share to diluted earnings

per share excluding merger related expenses, net of tax, and

FDIC special assessment, net of tax:

Diluted earnings per share (unadjusted)

1.16

1.49

1.45

1.42

1.37

Net income

116,267

139,907

137,556

135,155

130,225

Merger related expenses, net of tax (W)

33,588

212

—

FDIC special assessment, net of tax (W)

—

(2,807)

—

Net income excluding merger related expenses, net of tax, and FDIC

special assessment, net of tax (W):

149,855

137,312

137,605

135,155

130,225

Weighted average diluted shares outstanding

99,825

94,044

95,093

95,277

95,266

Merger related expenses, net of tax, per diluted common share (W)

0.34

—

FDIC special assessment, net of tax, per diluted common share (W)

—

(0.03)

—

Diluted earnings per share excluding merger related expenses, net of

tax, and FDIC special assessment, net of tax: (W)

1.50

1.46

1.45

1.42

1.37

Reconciliation of return on average assets to return on average

assets excluding merger related expenses, net of tax, and FDIC

special assessment, net of tax:

Return on average assets (unadjusted)

1.10

1.49

1.44

1.41

1.34

Net income excluding merger related expenses, net of tax, and FDIC

special assessment, net of tax (W):

149,855

137,312

137,605

135,155

130,225

Average total assets

42,219,608

37,665,928

38,129,863

38,391,214

38,957,078

Return on average assets excluding merger related expenses, net of

tax, and FDIC special assessment, net of tax (F) (W)

1.42

1.46

1.44

1.41

1.34

Reconciliation of return on average common equity to return on

average common equity excluding merger related expenses, net

of tax, and FDIC special assessment, net of tax:

Return on average common equity (unadjusted)

5.70

7.30

7.18

7.13

6.94

Net income excluding merger related expenses, net of tax, and FDIC

special assessment, net of tax (W):

149,855

137,312

137,605

135,155

130,225

Average shareholders' equity

8,160,782

7,668,802

7,657,978

7,586,290

7,505,801

Return on average common equity excluding merger related

expenses, net of tax, and FDIC

special assessment, net of tax (F) (W)

7.35

7.16

7.19

7.13

6.94

Reconciliation of return on average common equity to return on

average tangible common equity:

Net income

116,267

139,907

137,556

135,155

130,225

Average shareholders' equity

8,160,782

7,668,802

7,657,978

7,586,290

7,505,801

Less: Average goodwill and other intangible assets

(3,768,729)

(3,556,680)

(3,560,083)

(3,563,866)

(3,567,421)

Average tangible shareholders' equity

4,392,053

4,112,122

4,097,895

4,022,424

3,938,380

Return on average tangible common equity (F)

10.59

13.61

13.43

13.44

13.23

(W) Calculated assuming a federal tax rate of 21.0%.

Three Months Ended

Mar 31,

2026

Dec 31,

2025

Sep 30,

2025

Jun 30,

2025

Mar 31,

2025

Reconciliation of return on average common equity to return on

average tangible common equity excluding merger related

expenses, net of tax, and FDIC special assessment, net of tax:

Net income excluding merger related expenses, net of tax, and FDIC

special assessment, net of tax (W):

149,855

137,312

137,605

135,155

130,225

Average shareholders' equity

8,160,782

7,668,802

7,657,978

7,586,290

7,505,801

Less: Average goodwill and other intangible assets

(3,768,729)

(3,556,680)

(3,560,083)

(3,563,866)

(3,567,421)

Average tangible shareholders' equity

4,392,053

4,112,122

4,097,895

4,022,424

3,938,380

Return on average tangible common equity excluding merger related

expenses, net of tax, and FDIC special assessment, net of tax (F) (W)

13.65

13.36

13.43

13.44

13.23

Reconciliation of book value per share to tangible book value per share:

Shareholders' equity

8,207,851

7,616,140

7,664,938

7,599,736

7,517,061

Less: Goodwill and other intangible assets

(3,933,526)

(3,554,732)

(3,558,321)

(3,561,923)

(3,565,533)

Tangible shareholders' equity

4,274,325

4,061,408

4,106,617

4,037,813

3,951,528

Period end shares outstanding

100,835

93,058

94,993

95,277

95,258

Tangible book value per share

42.39

43.64

43.23

42.38

41.48

Reconciliation of equity to assets ratio to period end tangible

equity to period end tangible assets ratio:

Tangible shareholders' equity

4,274,325

4,061,408

4,106,617

4,037,813

3,951,528

Total assets

43,619,183

38,463,425

38,330,469

38,417,352

38,764,675

Less: Goodwill and other intangible assets

(3,933,526)

(3,554,732)

(3,558,321)

(3,561,923)

(3,565,533)

Tangible assets

39,685,657

34,908,693

34,772,148

34,855,429

35,199,142

Period end tangible equity to period end tangible assets ratio

10.77

11.63

11.81

11.58

11.23

Reconciliation of allowance for credit losses to total loans to

allowance for credit losses on loans to total loans excluding

Warehouse Purchase Program:

Allowance for credit losses on loans

383,840

333,742

339,626

346,084

349,101

Total loans

25,287,986

21,805,368

22,027,769

22,197,388

21,977,570

Less: Warehouse Purchase Program loans

(1,433,152)

(1,304,798)

(1,278,178)

(1,287,440)

(1,057,893)

Total loans less Warehouse Purchase Program

23,854,834

20,500,570

20,749,591

20,909,948

20,919,677

Allowance for credit losses on loans to total loans excluding

Warehouse Purchase Program

1.61

1.63

1.64

1.66

1.67

Reconciliation of efficiency ratio to efficiency ratio excluding net

gains and losses on the sale, write-down or write-up of assets:

Noninterest expense

217,287

138,712

138,635

138,565

140,301

Net interest income

321,150

274,953

273,435

267,722

265,382

Noninterest income

46,474

42,780

41,238

42,982

41,301

Less: net gain (loss) on sale or write-down of assets

318

1,414

(235)

Noninterest income excluding net gains and losses on the sale, write-

down or write-up of assets

46,156

42,745

41,235

41,568

41,536

Total income excluding net gains and losses on the sale, write-

down or write-up of assets

367,306

317,698

314,670

309,290

306,918

Efficiency ratio, excluding net gains and losses on the sale, write-

down or write-up of assets

59.16

43.66

44.06

44.80

45.71

Three Months Ended

Mar 31,

2026

Dec 31,

2025

Sep 30,

2025

Jun 30,

2025

Mar 31,

2025

Reconciliation of efficiency ratio to efficiency ratio, excluding net

gains and losses on the sale, write-down or write-up of assets,

merger related expenses and FDIC special assessment:

Noninterest expense

217,287

138,712

138,635

138,565

140,301

Less: merger related expenses

42,516

268

—

Less: FDIC special assessment

—

(3,554)

—

Noninterest expense excluding merger related expenses and FDIC

special assessment

174,771

141,998

138,573

138,565

140,301

Net interest income

321,150

274,953

273,435

267,722

265,382

Noninterest income

46,474

42,780

41,238

42,982

41,301

Less: net gain (loss) on sale or write down of assets

318

1,414

(235)

Noninterest income excluding net gains and losses on the sale, write-

down or write-up of assets

46,156

42,745

41,235

41,568

41,536

Total income excluding net gains and losses on the sale, write-

down or write-up of assets

367,306

317,698

314,670

309,290

306,918

Efficiency ratio, excluding net gains and losses on the sale, write-

down or write-up of assets, merger related expenses and FDIC

special assessment

47.58

44.70

44.04

44.80

45.71

SOURCE Prosperity Bancshares, Inc.