#1PROSPERITY BANCSHARES, INC. Investor Presentation Fourth Quarter 2022#22 "Safe Harbor" Statement Under the Private Securities Litigation Reform Act of 1995 "Safe Harbor" Statement under the Private Securities Litigation Reform Act of 1995: This release contains, and the remarks by Prosperity's management on the conference call may contain, forward-looking statements within the meaning of the federal securities laws, including Section 27A of the Securities Act of 1933, as amended, 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 Bancshares and its subsidiaries. These forward-looking statements may include information about Prosperity'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 future capital expenditures and dividends, future financial condition and changes therein, including changes in Prosperity'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 future operations, future or proposed acquisitions, including the proposed transactions with First Bancshares and Lone Star, the future or expected effect of acquisitions on Prosperity's operations, results of operations, financial condition, and future economic performance, statements about the anticipated benefits of each of the proposed transactions, and statements about the assumptions underlying any such statement, as well as expectations regarding the effects of the COVID-19 pandemic on Prosperity's operating income, financial condition and cash flows. 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 Prosperity's control, they are subject to inherent uncertainties, risks and changes in circumstances that are difficult to predict. Many possible events or factors could adversely affect the future financial results and performance of Prosperity, First Bancshares, Lone Star 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: the occurrence of any event, change or other circumstance that could give rise to the right of a party to terminate the merger agreement with First Bancshares or Lone Star, as applicable, the outcome of any legal proceedings that may be instituted against Prosperity, First Bancshares or Lone Star, delays in completing either of the transactions, the failure to obtain necessary regulatory approvals (and the risk that such approvals may result in the imposition of conditions that could adversely affect the combined company or the expected benefits of each of the transactions) or First Bancshares shareholder approval or Lone Star shareholder approval or to satisfy any of the other conditions to the transactions on a timely basis or at all, the possibility that the anticipated benefits of the transactions are not realized when expected or at all, including as a result of the impact of, or problems arising from, the integration of the two companies or as a result of the strength of the economy and competitive factors generally, or specifically in the West Texas area and the West, North and Central Texas area where First Bancshares and Lone Star, respectively, do a majority of their respective business and Prosperity has a significant presence, the possibility that the transactions may be more expensive to complete than anticipated, including as a result of unexpected factors or events, diversion of management's attention from ongoing business operations and opportunities, potential adverse reactions or changes to business or employee relationships, including those resulting from the announcement or completion of the transactions, Prosperity's ability to complete the acquisition and integration of First Bancshares and of Lone Star successfully, and the dilution caused by Prosperity's issuance of additional shares of its common stock in connection with the transactions. Prosperity disclaims 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 factors are discussed in Prosperity's Annual Report on Form 10-K for the year ended December 31, 2021, and other reports and statements Prosperity has filed with the Securities and Exchange Commission | ("SEC"). Copies of the SEC filings for Prosperity may be downloaded from the Internet at no charge from http://www.prosperitybankusa.com. PB LISTED NYSE#33 Important Information Additional Information about the First Bancshares Merger and Where to Find It In connection with the proposed merger of First Bancshares into Prosperity, Prosperity has filed with the SEC a registration statement on Form S-4 to register the shares of Prosperity common stock to be issued to the shareholders of First Bancshares. The registration statement includes a preliminary proxy statement/prospectus. The definitive proxy statement/prospectus will be sent to the shareholders of First Bancshares seeking their approval of the proposed transaction. WE URGE INVESTORS AND SECURITY HOLDERS TO READ THE REGISTRATION STATEMENT ON FORM S-4, THE PROXY STATEMENT/PROSPECTUS INCLUDED WITHIN THE REGISTRATION STATEMENT ON FORM S-4 AND ANY OTHER RELEVANT DOCUMENTS TO BE FILED WITH THE SECURITIES AND EXCHANGE COMMISSION IN CONNECTION WITH THE PROPOSED TRANSACTION BECAUSE THEY CONTAIN IMPORTANT INFORMATION ABOUT PROSPERITY, FIRST BANCSHARES AND THE PROPOSED TRANSACTION. Investors and security holders may obtain free copies of these documents through the website maintained by the SEC at http://www.sec.gov. You will also be able to obtain these documents, when they are filed, free of charge, from Prosperity at http://www.prosperitybankusa.com. Copies of the proxy statement/prospectus can also be obtained, when it becomes available, free of charge, by directing a request by telephone or mail to Prosperity Bancshares, Inc., Prosperity Bank Plaza, 4295 San Felipe, Houston, Texas 77027 Attn: Investor Relations, (281) 269-7199 or to First Bancshares of Texas, Inc., 310 West Wall Street, Suite 1200, Midland, Texas 79701, Attention: Ken Burgess, (844) 322-8392. Additional Information about the Lone Star Merger and Where to Find It In connection with the proposed merger of Lone Star into Prosperity, Prosperity has filed with the SEC a registration statement on Form S-4 to register the shares of Prosperity common stock to be issued to the shareholders of Lone Star. The registration statement includes a proxy statement/prospectus. The definitive proxy statement/prospectus will be sent to the shareholders of Lone Star seeking their approval of the proposed transaction. WE URGE INVESTORS AND SECURITY HOLDERS TO READ THE REGISTRATION STATEMENT ON FORM S-4, THE PROXY STATEMENT/PROSPECTUS INCLUDED WITHIN THE REGISTRATION STATEMENT ON FORM S-4 AND ANY OTHER RELEVANT DOCUMENTS TO BE FILED WITH THE SECURITIES AND EXCHANGE COMMISSION IN CONNECTION WITH THE PROPOSED TRANSACTION BECAUSE THEY CONTAIN IMPORTANT INFORMATION ABOUT PROSPERITY, LONE STAR AND THE PROPOSED TRANSACTION. Investors and security holders may obtain free copies of these documents through the website maintained by the SEC at http://www.sec.gov. You will also be able to obtain these documents, when they are filed, free of charge, from Prosperity at http://www.prosperitybankusa.com. Copies of the proxy statement/prospectus can also be obtained, when it becomes available, free of charge, by directing a request by telephone or mail to Prosperity Bancshares, Inc., Prosperity Bank Plaza, 4295 San Felipe, Houston, Texas 77027 Attn: Investor Relations, (281) 269-7199 or to Lone Star State Bancshares, Inc., 6220 Milwaukee Avenue, Lubbock, Texas 79424, Attention: Alan Lackey, (806) 771-7717. Participants in the Solicitation Prosperity, First Bancshares and their respective directors and executive officers may be deemed to be participants in the solicitation of proxies from the shareholders of First Bancshares in connection with the proposed transaction. Certain information regarding the interests of these participants and a description of their direct and indirect interests, by security holdings or otherwise, is included in the registration statement and proxy statement/prospectus regarding the proposed transaction and other relevant materials to be filed with the SEC when they become available. Prosperity, Lone Star and their respective directors and executive officers may be deemed to be participants in the solicitation of proxies from the shareholders of Lone Star in connection with the proposed transaction. Certain information regarding the interests of these participants and a description of their direct and indirect interests, by security holdings or otherwise, is included in the registration statement and proxy statement/prospectus regarding the proposed transaction and other relevant materials to be filed with the SEC when they become available. Additional information about Prosperity and its directors and executive officers may be found in the definitive proxy statement of Prosperity relating to its 2022 Annual Meeting of Shareholders filed with the SEC on March 14, 2022, and other documents filed by Prosperity with the SEC. These documents can be obtained free of charge from the sources described above. 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 of 1933, as amended, and otherwise in accordance with applicable law. PB LISTED NYSE#4Fourth Quarter Highlights . Net income of $137.9 million and earnings per share (diluted) of $1.51 for three months ended December 31, 2022 • Assets of $37.7 billion, total loans of $18.8 billion, and deposits of $28.5 billion at December 31, 2022 • Common equity tier 1 ratio of 15.88% and leverage ratio of 10.16% at December 31, 2022 • Loans, excluding Warehouse Purchase Program and SBA Paycheck Protection Program Loans, increased $518.5 million or 3.0% (11.8% annualized) during the fourth quarter 2022 • Sound asset quality with annualized net charge-offs/quarterly average loans of 0.01% • Nonperforming assets to average earning assets remain low at 0.08% or $27.5 million for the fourth quarter 2022 • Allowance for credit losses on loans and on off-balance sheet credit exposure of $311.5 million • Allowance for credit losses to total loans, excluding Warehouse Purchase Program and SBA Paycheck Protection Program loans, of 1.56% Efficiency ratio of 40.9% for the fourth quarter 2022 • Declared cash dividend of $0.55 for the first quarter 2023 4 Source: Company Documents PB LISTED NYSE#5Strong Presence in Texas and Oklahoma • A Texas-based financial holding company with $37.7 billion in total assets • Prosperity has been ranked in the Top 10 of Forbes America's Best Banks since the list's inception in 2010, and was ranked #6 in 2022 Ranked #2 in deposit market share in Texas (1) Texas and Oklahoma continue to benefit from strong economies, and are home to 56 Fortune 500 headquartered companies • Shareholder driven with 4.2% fully diluted insider ownership (2) Successful completion of 43 acquisitions (whole bank, branch and failed bank transactions) El Paso Amarillo 27 Midland Odessa 10. 5 (1) (2) 272 Full-Service Locations 16 in Bryan/College Station Area 6 in Central Oklahoma Area 29 in Central Texas Area 62 in Dallas/Fort Worth Area 22 in East Texas Area 65 in Houston Area 30 in South Texas Area 8 in Tulsa Area 34 in West Texas Area Per FDIC; Includes Texas headquartered commercial banks; Deposits as of 6/30/2022 Per proxy statement (Form DEF 14A) filed on 3/14/2022 Oklahoma 44 Tulsa Oklahoma City Lubbock Fort Worth Dallas Abilene Texas Houston 10 Austin San Antonio Victoria Laredo Corpus Christi PB LISTED NYSE#69 Balance Sheet Summary ($ in millions) $40,000 Data as of 12/31/2022 Total Loans Deposits Assets $35,000 10 Year CAGR (¹) $30,000 Loans Deposits Assets $25,000 $20,000 $15,000 $10,000 $5,000 $18.8 Bn $28.5 Bn $37.7 Bn ° 13.8% 9.4% 10.0% ° ° $7,000 ° $6,000 $5,000 $4,000 $3,000 $2,000 $1,000 $0 $0 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022 4Q21 4Q22 Assets Deposits Total Loans Equity Source: Company Documents (1) Represents the Compound Annual Growth Rate from 12/31/2012 - 12/31/2022 PB LISTED NYSE#7Net Income $600.0 10 Year Core CAGR: (1) 12.8% (2) 5 Year Core CAGR: 14.9% $500.0 $528.9 $519.3 $524.5 $518.5 $487.8 $452.4 $321.8 $332.6 $311.7 $297.4 $309.6 $286.6 $274.5 $272.2 $255.5 $250.6 $259.3 $236.2 $221.4 $185.7 $154.9 $400.0 $300.0 $200.0 $167.9 $100.0 $0.0 2012 2013 $126.8 $122.6 $137.9- $137.1 (3) 2014 2015 2016 2017 2018 2019 2020 2021 2022 4Q21 4Q22 Note: Net income includes the following ($ in thousands) Provision for Credit Losses $6,100 $17,240 $18,275 $7,560 $24,000 $14,325 $16,350 $4,300 $20,000 Loan Discount $26,413 $62,723 Accretion $95,875 $52,122 $38,970 $21,906 $13,909 $28,045 $91,341 $39,278 $7,401 $5,366 $913 Net Income Net Income (Excluding Purchase Accounting Adjustments) Source: Company Documents (1) 7 (2) (3) Represents the Compound Annual Growth Rate of net income (excluding purchase accounting adjustments) from 12/31/2012 - 12/31/2022 Represents the Compound Annual Growth Rate of net income (excluding purchase accounting adjustments) from 12/31/2017 - 12/31/2022 Includes NOL tax benefit of $20.145 million related to the CARES Act PB LISTED NYSE#8Earnings Per Share $6.00 10 Year Core EPS CAGR:(¹) 6.6% 5 Year Core EPS CAGR:(2) 8.7% $5.00 $4.32 $4.09 $4.00 $3.65 $3.94 $3.65 $3.60 $3.43 $5.73 $5.68 $5.60 $5.66 $5.26 $4.86 $4.61 $4.52 $4.46 $4.21 $3.92 $3.73 $3.23 $2.98 $3.07 $3.00 $2.00 $1.51 $1.38 $1.50 $1.33 $1.00 $0.00 2012 2013 (3) 2014 2015 2016 2017 2018 2019 2020 2021 2022 4Q21 4Q22 Note: Net income includes the following ($ in thousands) Provision for Credit Losses $6,100 $17,240 $18,275 $7,560 $24,000 $14,325 $16,350 $4,300 $20,000 Loan Discount $26,413 $62,723 Accretion $95,875 $52,122 $38,970 $21,906 $13,909 $28,045 $91,341 $39,278 $7,401 $5,366 $913 EPS Core EPS (Excluding Purchase Accounting Adjustments) 80 Source: Company Documents Represents the Compound Annual Growth Rate for EPS (excluding purchase accounting adjustments) from 12/31/2012 - 12/31/2022 Represents the Compound Annual Growth Rate for EPS (excluding purchase accounting adjustments) from 12/31/2017 - 12/31/2022 (1) (2) (3) Includes NOL tax benefit of $20.145 million related to the CARES Act PB LISTED NYSE#9Net Interest Margin 3.90% 6 3.70% 3.58% 3.53% 3.50% 3.35% 3.30% 3.10% 2.90% 2.70% 3.80% 3.64% 3.38% 3.35% 3.29% 3.20% 3.32% 3.30% 3.19% 3.18% 3.18% 3.16% 3.13% 3.12% 3.09% 3.14% 3.05% 3.00% 3.04% 3.02% 2.98% 2.97% 2.91% 2.50% 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022 4Q21 4Q22 Source: Company Documents Net Interest Margin (Tax Equivalent) Net Interest Margin (Excluding Purchase Accounting Adjustments) PB LISTED NYSE#10Acquisitions & Efficiency Ratio ($'s in millions) $45,000 $40,000 $35,000 $34,059 $32,186 $37,834 $37,690 $37,834 $37,690 $30,000 $25,000 $21,508 $22,331 $22,037 $22,587 $22,693 $20,000 $18,642 48.3% 43.5% 41.6% 41.8% 41.9% 42.5% 42.8% 43.7% 42.6% 41.8% 42.2% 42.8% 40.9% $15,000 $14,584 $10,000 $5,000 $0 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022 4Q21 4Q22 % of Assets Acquired 23.7% 20.9% 11.2% 0.0% 2.5% 0.0% 0.0% 31.3% 0.0% 0.0% 0.0% 0.0% 0.0% Total Assets Excluding Acquisitions Total Assets Acquired (1) Efficiency Ratio (2) Source: Company Documents (1) Representative of target assets at closing 10 (2) Calculated by dividing total noninterest expense, excluding credit loss provisions, by net interest income plus noninterest income, excluding net gains and losses on the sale or write down of assets and securities. Additionally, taxes are not part of this calculation. PB LISTED NYSE#11Return on Average Tangible Common Equity 40.00% 30.00% 20.00% 10.00% 24.24% 22.52% 21.93% 19.98% 16.95% 16.00% 15.06% 14.23% ($ in millions) $3,800 $2,850 19.83% $1,900 17.18% 16.26% 16.26% 15.94% $950 0.00% $0 (2) (1) (1) 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022 4Q21 4Q22 ROATCE (1) Interim periods shown on an annualized basis 11 (2) Includes NOL tax benefit of $20.145 million related to the CARES Act Tangible Common Equity PB LISTED NYSE#12Return on Average Assets 2.00% 1.75% 1.50% 1.44% 1.35% 1.36% 1.25% 1.00% 1.33% 1.25% 1.22% 1.42% 1.38% 1.62% 1.44% 1.47% 0 1.39% 1.37% 0.75% (2) (1) (1) 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022 4Q21 4Q22 12 (1) Interim periods shown on an annualized basis (2) Includes NOL tax benefit of $20.145 million related to the CARES Act PB LISTED NYSE#13Deposit Composition As of December 31, 2022 ($ in millions) Money Market & Savings 33.8% CDs & Other Time 7.0% Interest-Bearing Demand 21.0% $mm Cost (%) (1) Noninterest-Bearing Demand Interest-Bearing Demand $10,915 0.00% $5,986 0.22% Money Market & Savings $9,636 1.13% Bearing Demand Noninterest- 38.2% CDs & Other Time $1,996 0.94% Source: Company Documents Data for the three months ended December 31, 2022 13 (1) Total Deposits: $28.5Bn Total Cost of Deposits: 0.50% (1) Cost of Interest-Bearing Deposits: 0.81% (1) PB LISTED NYSE#14Loan Growth ($ in millions) $22,000 $19,800 $17,600 100.0% $20,247 $18,845 $18,616 $18,840 92.5% $2,842 $741 $1,553 $1,776 85.0% $15,400 77.5% $77.9% $13,200 74.0% 70.0% 66.0% 71.5% 60.5% $11,000 $10,370 $9,244 $9,439 $9,622 $10,021 62.5% $8,800 $7,775 60.1% 56.2% 63.6% 54.7% 63.4% 55.0% $6,600 $5,180 52.2% 53.4% 55.6% 50.8% 47.5% 44.5% $4,400 40.0% $2,200 32.5% $0 25.0% 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022 14 Source: Company Documents Loans (Excluding Warehouse Purchase Program) Warehouse Purchase Program (WPP) -- Loan / Deposit Ratio (Excluding WPP) Loan / Deposit Ratio (Including WPP) PB LISTED NYSE#15Loan Portfolio Overview As of December 31, 2022 ($ in millions) Loan Portfolio by Category & Geography Consumer & Other $284 1.5% Home Equity $967 5.1% Construction $2,805 14.9% Comm. R.E. $4,986 26.5% Loans by Rate Structure Floating 29.7% C&I $2,159 11.5% Energy $429 2.3% Agriculture Fixed 42.5% ~3.1yr Avg. Life (Inc. Farm) $688 3.6% 1-4 Family $5,775 30.6% PPP Loans $6 Variable Rate 27.8% WPP 0.1% $741 3.9% Loans By Area Amount (2)(4) % of Total Bryan College Station $769 4.3% Central Oklahoma $633 3.5% Central Texas Dallas/Ft. Worth East Texas Houston $2,291 12.7% $6,397 35.4% $731 4.0% $4,172 23.1% South Texas $1,413 7.8% Tulsa $577 3.2% West Texas $1,078 6.0% Source: Company Documents (1) (2) 15 (3) (4) Data for the three months ended December 31, 2022 Excludes $38 million in loans assigned to the Corporate Group Core yield excludes purchase accounting adjustments Excludes Warehouse Purchase Program (WPP) loans Total Loans: $18.8Bn Loans HFI (Excl. WPP): $18.1Bn Yield on Total Loans: 5.02% (1) Yield on Loans HFI (Excl. WPP): 4.98%(1) Core Yield on Loans HFI (Excl. WPP): 4.96% (1)(3) PB LISTED NYSE#16Loan Portfolio Detail As of December 31, 2022 ($ in millions) • • Portfolio Commentary Loan portfolio is diversified across the Bank's market areas and by underlying collateral type 34% of commercial real estate is owner occupied • CRE and construction loans conservatively underwritten to cost of collateral C&I Detail (Excluding Energy Loans) ($ in millions) Financial Services Commercial Real Estate Detail ($ in millions) Other Com. & Industrial Retail Industrial $1,286 26% $980 20% Office Other $855 17% $4,986mm Total Office $739 15% Medical $383 8% Medical Multifamily (MF) $375 8% Retail MF Hotels Hotels $368 6% ($ in millions) Construction Detail Single Family (SF) $1,097 39% R.E. & Raw Land Resi. & Com. Lots $421 15% Financial Services $633 29% Other Const. Raw Land $333 12% R.E. & Const. $479 22% MF Lots Other $246 9% Manuf./Indust. $337 16% $2,159mm Manuf./ Retail $206 10% Total Indust. $2,805mm Total(2) LD Multifamily (MF) $230 8% Office Land Dev. (LD) $182 6% Medical $91 4% Office $164 6% Retail Other Transportation (1) $69 3% Retail Retail $81 3% Other $344 16% SF Hotels Medical $50 2% Medical Medical Hotels $1 0% Transportation Source: Company Documents Includes State & Political loans (2) Total includes a net unaccreted discount of ($14,000) not shown in graph 16 (1) PB LISTED NYSE#17Loan Portfolio Detail (Continued) As of December 31, 2022 ($ in millions) Energy Detail - Outstanding Balance ($ in millions) Service Providers $220 Portfolio Commentary Total energy loan loss reserves of 2.1%, or $9.2 million (excluding fair value marks)(1) 51% $429mm Total(1) Reserve-based $209 49% $9.5 million, or 2.2% of energy loans, are subject to fair value marks of $0.3 million in addition to general and specific loan loss reserves Energy Detail - Unfunded Commitments ($ in millions) Portfolio is company-led with only 3 Shared National Credits (SNC), all of which were originated and syndicated by Prosperity Service Providers 17 (1) $96 21% $453mm Total Reserve-based $357 79% Source: Company Documents Amount shown net of discount related to purchase accounting; Excludes PPP loans Portfolio focused on lending on proven producing reserves and therefore not dependent on ongoing development PB LISTED NYSE#18Changes to Allowance for Credit Losses ($ in millions) 1.61% ACL to Total Loans (1) $282.2 Allowance for Credit Losses Allowance for Unfunded Commitments (Other Liabilities) 18 (1) $7.3 1.56% ACL to Total Loans (1) ($0.6) ($6.2) ■ Net Charge-offs ■ PCD recoveries ■ $6.2 million released related to resolved PCD loans without any charge offs during the fourth quarter ($1.1) Outstanding balances ■ Historical loss rates ■ Non-PCD specific reserves ■Net increased reserve related to changes in macro-economic conditions and qualitative economic outlook $281.6 Allowance for Credit Losses Allowance for Unfunded Commitments (Other Liabilities) $29.9 $29.9 Q3 2022 ACL Portfolio Changes Portfolio Changes Portfolio Changes Environmental Outlook Q4 2022 ACL Excludes Warehouse Purchase Program (WPP) and SBA Paycheck Protection Program (PPP) loans PB LISTED NYSE#19Asset Quality NPAS/Loans + OREO 6.00% 5.00% 4.00% 4.98% 5.36% 4.72% 3.00% 2.74% 2.32% 2.00% 1.55% 1.17% 1.06% 0.96% 0.94% 0.97% 1.00% 0.49% 0.66% 0.60% 0.70% 0.48% 0.40% 0.45% 0.32% 0.25% 0.29% 0.40% 0.46% 0.53% 0.50% 0.37% 0.33% 0.18% 0.29% 0.15% 0.15% 0.00% 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022 Source: Company Documents & Uniform Bank Performance Report Note: NPAs include loans past due 90 days and still accruing 19 (1) (1) UBPR Peer Group Prosperity Bank UBPR = Uniform Bank Performance Report; Peer Group 2 (111 banks) - Insured commercial banks having assets between $10 billion and $100 billion PB LISTED NYSE#20Asset Quality Net Charge-Offs/Average Loans 2.00% 1.74% 1.66% 1.50% 0.96% 1.00% 0.98% 0.52% 0.26% 0.50% 0.29% 0.20% 0.41% 0.41% 0.17% 0.21% 0.17% 0.16% 0.15% 0.20% 0.16% 0.23% 0.00% 0.18% 0.14% 0.18% 0.16% 0.14% ($ in millions) 0.10% 0.16% Net Charge-Offs 0.04% 0.05% 0.08% 0.08% 0.03% 0.03% 0.02% 0.01% (2) (2) $31.9 (3) $29.7(3) $5.6 $7.6 $13.9 $13.9 $20.1 $5.2 $5.1 $2.5 $4.8 $6.9 $15.6 $14.0 $3.3 $4.8 $0.8 $0.6 (3) (3) Net PCD Recoveries $46.3 (3) $24.6(3) (3) $8.2 $1.75) $6.2(3) 20 20 2007 2008 2009 2010 2011 (1) 2012 2013 2014 2015 2016 UBPR Peer Group 2017 2018 2019 2020 2021 2022 4Q21 4Q22 Prosperity Bank (3) Non-Acquired Loan Charge-Offs Acquired Loan Charge-Offs Pre-CECL Note: NPAs include loans past due 90 days and still accruing (3) 223 (1) (2) Source: Company Documents & Uniform Bank Performance Report UBPR = Uniform Bank Performance Report; Peer Group 2 (111 banks) - Insured commercial banks having assets between $10 billion and $100 billion Interim period net charge-off ratios shown on an annualized basis Reflects all charge-offs and recoveries on acquired loans in accordance with CECL accounting practices; Prior to the adoption of CECL in the first quarter of 2020, PCD loans were classified as Purchased Credit Impaired (PCI) loans and their assigned fair-value marks were netted against the outstanding loan balance with a charge-off only being recorded when the loss exceeded the amount of fair-value marks remaining. Acquired Loan Charge-Offs Post-CECL Net PCD Recoveries Post-CECL (3) PB LISTED NYSE#21Securities Portfolio Detail As of December 31, 2022 ($ in millions) 21 (1) Mortgage- Backed Securities 94.7% Other Securities 0.1% States & Political Subdivisions 0.8% 96.8% Held to Maturity 3.2% Available for Sale $mm Mortgage-Backed Securities $13,713 Collateralized Mortgage Obligations $629 Collateralized States & Political Subdivisions $122 Mortgage Obligations 4.4% Other Securities $12 Total Securities: $14.5Bn Yield on Securities: 1.96% (1) Duration: 4.5 Yrs. (2) Avg. Yearly Cash Flow: ~$2.2Bn Source: Company Documents Data for the three months ended December 31, 2022 (2) Effective duration +300bps shown; Effective duration -300bps equal to 4.4 years; Weighted average life equal to 5.3 years PB LISTED NYSE#22Total Return Performance IPO (November 12, 1998) to December 30, 2022 22 22 2,000 1,800 1,600 1,400 1,200 1,000 800 600 400 200 $100,000 invested in Prosperity's IPO on 11/12/98 was worth $1,845,013 on 12/30/22 0 11/12/98 11/12/00 11/12/02 11/12/04 11/12/06 11/12/08 11/12/10 11/12/12 11/12/14 11/12/16 11/12/18 11/12/20 11/12/22 PB (+1,745.0%) S&P 500 (+439.5%) NASDAQ BANK (+125.4%) Source: S&P Global. Market data as of 12/30/2022. PB LISTED NYSE#23Presence in Fast-Growing Markets Positioned in Strong Markets Lubbock Fort Worth Dallas Midland Odessa Abilene Austin San Antonio. Houston Corpus Christi Today, Texas is the 2nd largest state in the U.S by population with over 29 million residents Ranked #1 on the Fortune 500 list with 53 headquartered companies in 2022 Ranked #1 state for business for the 9th consecutive time by U.S. corporate executives in an International Economic Development Council survey Top 10 Fastest Growing MSAs in the U.S. (1) Metropolitan Statistical Area Austin-Round Rock-Georgetown, TX Raleigh-Cary, NC Jacksonville, FL Orlando-Kissimmee-Sanford, FL Nashville-Davidson--Murfreesboro--Franklin, TN 2023 - 2028 Population Growth Prosperity Prosperity Presence Deposits ($mm) $1,491 7.8% 7.4% 6.9% 6.3% 6.1% 23 (1) Tulsa • Oklahoma City • Oklahoma City and Tulsa MSAs comprise over 60% of the state's population Oklahoma is home to 3 of the 2022 Fortune 500 Companies Top 4 state for production of natural gas, net electricity generation from wind, and production of crude oil • Oklahoma is one of the top 5 producers of wheat in the United States Charlotte-Concord-Gastonia, NC-SC 5.8% Tampa-St. Petersburg-Clearwater, FL 5.2% San Antonio-New Braunfels, TX $585 5.0% Dallas-Fort Worth-Arlington, TX $8,161 5.0% Houston-The Woodlands-Sugar Land, TX $6,677 4.8% Presence in the four of the fastest growing MSAs in the United States Source: S&P Global, Worldpopulationreview.com, Statista, U.S. Energy Information Administration, Forbes, Fortune and Oklahoma Commerce. Includes MSAs with greater than one million in total population. Deposit data as of 6/30/2022. PB LISTED NYSE#24Corporate Relocations to Texas California Aatonomy AccentCare Active Networks AEND Industries, Inc. AECOM The Allen Group, Inc. Allied Electronic Recycling AllyMe Group, Inc. ALL-Q-TELL Corp. Amazing Magnets Ameriflight LLC Aviat Networks, Inc. Aviatrix Banker's Toolbox, Inc. Boreland Software Corporation Caliber Collision Centers Calpine CCRA Travel Solutions Channell Commercial Corp. CompassLearning Consolidated Electrical Distributors Copart (CPRT) Core-Mark Daegis, Inc. (DAEG) DASAN Zhone Solutions, Inc. DBG Digital Realty Dimensional Fund Advisors DMX MUSIC, Inc. DynaPump, Inc. EDM Labortories Epicore Software Corporation Farmer Brothers (FARM) Finical, Inc. Firefly Space Systems First Foundation, Inc. Fluor Corporation (FLR) Freebirds World Burrito Fonality Green Dot Glenmount Global Solutions Harmonate HBCI HUB Hewlett Packard Enterprise HID Global Hutto Ironclad Performance Wear Corp. Jacobs Engineering Jamba Juice Company Kubota Liberty Fitness Holdings, LLC. loanDepot, LLC Marco Fine Arts MC Endeavors, Inc. (MSMY) McKesson Corp (MCK) MDB Capital Mitratech Monkey Sports Inc. MVTransportation Noodoe EV Occidental Ptetroleum (OXY) OmniTracs Oracle Corporation OriginClear, Inc. Pacific Union Financial Pain Therapeutics (PTIE) Primoris Services Corporation (PRIM) Quality Custom Distribution Services, Inc. QuestionPro Inc. R2Sonic Red Mango, Inc. Review Wave Revionics, Inc. Rifle Gear Right On Brands, Inc. Sanyo Energy Sionix Corp. (SINX) Solera Holdings (SLH) Sovereign Flavors Superconductor Technologies (SCON) Telmar Network Technology, Inc. Tenet Healthcare (THC) Tesla, Inc. (TSLA) Thermasol Toyota USA (TM) Trend Micro (TYO.4704) Vendor Resource Management Vermillion, Inc. (VRML) Visual Numerics W3global Waste Connections, Inc. (WCN) Websense Xeris Pharmaceuticals Oregon Socati Corp. Washington LifeLast, Inc. National Scooter Co. Prometheous Energy Company Crowdstreet, Inc. Nevada CoreSpace 24 - Corporate Relocations to Texas (2004 – Present) Montana ViZn Canada Absolute Software (ABT) Bio-Solutions Corp (BISU) Direct Energy Mitel Corp (MITL) QI Systems Inc. MoneyGram (MGI) Speed Commerce Minnesota American Environmental Energy, Inc. (AEEI) EmpowerMX LecTec Corp. Enerlex Resources, Inc. Ottobock Healthcare MoneyGram (MGI) Resideo Technologies Inc. Speed Commerce Illinois BL Restaurant Group Eleiko Ferris Manufacturing MedMark Services, Inc. Monolith Technology Hldgs, LLC Neovia Logistics RMG Networks (RMGN) Schumacher Electric State Farm SolarBridge Technologies, Inc. Top Golf Boeing (Global Services Business) Great Lakes Dredge & Dock Corporation Caterpillar Parus Interactive, Inc. Extenet Systems Colorado Cagney Global Logistics Global Clean Energy, Inc. (GCE) Heartland Oil & Gas Corp. Magpul Industries Par Petroleum Corporation (PARR) Quovadx Sun River Energy, Inc. (SNRV) Kansas Nebraska Heartland Automotive Services Alco Stores (ALCS) Layne Christensen Co.(LAYN) Lulu's Dessert Corp Enerlex Resources, Inc. Missouri Kupper Parker Comm. PotentiaMetrics Emerson Process Management ulrich medical USA, Inc. Elite Advanced Polymers Arizona Quest Resource Holdings Corp. (QRHC) Oklahoma Casedhole Solutions, Inc. CITGO Petroleum Corp Global Power Equipment Group Hilti North America. LinkAmerica NATCO Group, Inc. Petrohwk Energy Corp Ring Energy, Inc. (REI) Soalr Winds (SWI) Trinity Hospice Inc. Arkansas Golden Living US Rare Earths Inc. (UREE) Murphy Oil Corporation (MUR) Tennessee Elite Data Services, Inc. (DEAC) Miller Energy Resources, Inc. Forward Air Corp. (FWRD) Louisiana Bristow Group, Inc. (BRS) EPL Oil & Gas, Inc. Fluence Analytics NGC Transmission New York American Locker Group Inc. (ALGI) DataTreasury Corp Fiesta Restaurant Group (FRGI) Greatbatch (GB) HMS Holdings (HMSY) Six Flags Entertainment (SIX) Signature Systems Group Visionworks of America JP Morgan (6,000 workers) Banorte-Ixe Securities International, LTD DarkPulse Alkegen Michigan Comerica (CMA) Cambium Learning (ABCD) Massachusetts Cimage Novasoft Circor Energy (CIR) Invensys Process Systems Liberty Mutual NTT Data Inc. (TYO.9613) VCE Corp. Raytheon Ohio Pennsylvania Big Brothers Big Sisters Hyllion Linn Energy, LLC (LINE) MPOWER Mobile Union Drilling, Inc. CDI Engineering Archaea Energy ATI Inc. Covington Group, Inc. Robbins & Myers CyrusOne (CONE) Victory Capital Washington D.C. Maryland Broadwing Corp. Hanger Inc. (HGR) New Jersey Ameriflex CVE Technology Comparex USA Creston Electronics Honeywell PMT Geico Insurance Division 5G LLC EF Johnson Technologies, Inc. North Carolina Dex Media (DXM) Mississippi Elite Advanced Polymers Alabama Georgia Cyntech Technologies (CYNT) NYLO Hotels Torchmark Corporation (TMK) Zoes Kitchen (ZOES) Florida CCS Medical DreamVision iWorld Projects & Systems, Inc. (IWPS) Likewize Optym PGA of America Puget Technologies, Inc. (PUGE) SoftServe QSAM Biosciences Firehawk Aerospace Virginia Capital One Connecticut Accudyne Industries iCall Inc. TradeCapture Inc. PB LISTED NYSE#2525 • • • • Houston Market Highlights Market Highlights Houston MSA is the 5th largest in the United States by population with nearly 7.4 million residents - Population is expected to grow 4.8% from 2023 - 2028 Home to NASA's Johnson Space Center and Texas Medical Center - the world's largest medical complex As of November 2022, total nonfarm employment has increased 5.6% YoY, compared to the 12 month statewide increase of 5.1% and the nationwide increase of 2.3% - Employment in Houston has increased 15.8% YoY in the leisure and hospitality sector and 8.6% YoY in construction, compared to 11.9% and 3.9% statewide, respectively Houston has the largest export market in the U.S. The Port of Houston is ranked 1st in the U.S. in international waterborne tonnage and in total waterborne tonnage handled Select Fortune 500 Companies Houston Franchise 45 10 Houston PHILLIPS Good things 66 HALLIBURTON come from Sysco ConocoPhillips OXY Seogr eog resources GROUP AUTOMOTIVE Baker > Hughes nrg Enterprise Products PLAINS WM WASTE MANAGEMENT QUANTA SERVICES CenterPoint. Energy Westlake Chemical NOY KINDER MORGAN TARGA CHENIERE CC CROWN CASTLE Hewlett Packard Enterprise KBR HUNTSMAN Enriching lives through innovation Academy SPORTS OUTDOORS Source: S&P Global, Houston.org, Bureau of Labor Statistics, Forbes.com, Port Houston, Greater Houston Partnership, Houston Properties. References to Houston refer to the Houston - The Woodlands - Sugar Land metropolitan statistical area. PB LISTED NYSE#2626 • Dallas/Ft. Worth Market Highlights • • Market Highlights Dallas/Ft. Worth MSA is the 4th largest in the United States by population with over 7.9 million residents - Population is expected to grow 5.0% from 2023 - 2028 As of November 2022, total nonfarm employment has increased 6.1% YoY, compared to the 12 month statewide increase of 5.1% and the nationwide increase of 2.3% - Unemployment rate is 3.3%, down from 4.9% in August 2021 As of November 2022, employment increased 8.2% YoY in Mining, Logging and Construction and 6.2% in Financial Activities - Among the 12 largest MSAs by population, Dallas had both the highest YoY increase in employment in financial activities and total nonfarm employment Headquarters to 22 Fortune 500 companies Select Fortune 500 Companies Dallas/Ft. Worth Franchise Irving 30 Garland 20 Dallas Fort Worth Arlington ExxonMobil AT&T American Airlines ENERGY TRANSFER Group tenet HEALTH Southwest Kimberly-Clark FLUOR Ħ TEXAS INSTRUMENTS HOLLYFRONTIER JACOBS AECOM MCKESSON CBRE Builders 35 PIONEER NATURAL RESOURCES Celanese D-R HORTON America's Builder CMC Commercial Metals VISTRA ENLINK charles SCHWAB ENERGY MIDSTREAM Source: S&P Global, Bureau of Labor Statistics, Dallasnews.com, Wfaa.com, Star-telegram.com, The Brookings Institution, Fortune.com. References to Dallas refer to the Dallas-Fort Worth - Arlington metropolitan statistical area. 45 PB LISTED NYSE#2727 • • • • Austin Market Highlights Market Highlights Population grew by 33% from 2010 to 2020, the highest of any major MSA in the country Ranks first among MSAs for new residents as a percent of total population Expected population growth of 7.8% from 2023 - 2028 As of November 2022, total nonfarm employment has increased 4.7% YoY, compared to the 12 month statewide increase of 5.1% and the nationwide increase of 2.3% - Unemployment rate is 2.8%, compared to 4.0% statewide and 3.4% nationwide Employment in Austin has increased 19.4% YoY in the leisure and hospitality sector and 9.2% YoY in manufacturing, compared to 11.9% and 5.3% statewide, respectively 15 companies have begun operations and 15 companies expanded their existing operations in the Austin-Round Rock MSA in Q4 2022 Austin-Round Rock ranks 2nd for best MSA for STEM professionals amongst the top 100 MSAs Select Fortune 500 Companies amazon ebay ORACLE 8 Meta CISCO 10 San Antonio T TESLA 3M IBM intel) Google (DELL Austin Franchise 35 Round Rock Austin Source: S&P Global, Bureau of Labor Statistics, Forbes, U.S. News and World Report, and Austin Chamber. References to Austin refer to the Austin - Round Rock - San Marcos metropolitan statistical area. PB LISTED NYSE#28Dividend History $2.25 (a) $2.11 $1.99 $2.00 Compounded Annual Growth Rate from 2003-2022 was 11.9% $1.87 $1.75 $1.69 $1.49 $1.50 $1.38 $1.24 $1.25 $1.12 $0.99 $1.00 $0.89 $0.80 $0.72 $0.75 $0.64 2023 Dividend History $0.57 $0.51 $0.46 $0.55 $0.50 $0.41 $0.35 $0.31 $0.25 $0.25 $0.00 Q1 (Declared) 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022 28 (a) 2022 dividend consists of $0.52 per share declared in Q1 2022, 2Q 2022, 3Q 2022 and $0.55 per share declared in 4Q 2022 PB LISTED NYSE#2929 Contact Information Corporate Headquarters Prosperity Bank Plaza 4295 San Felipe Houston Texas 77027 281-269-7199 Telephone Investor Contacts David Zalman Chairman & CEO 979-543-2200 [email protected] Cullen Zalman SVP - Banking & Corporate Activities 281-269-7176 [email protected] PB LISTED NYSE