Prosperity Bancshares (PRSP)

Capital Resources

Total shareholders’ equity was $1.28 billion at March 31, 2009 compared with $1.26 billion at December 31, 2008, an increase of $25.4 million or 2.0%. The increase was due primarily to net earnings of $25.5 million and an increase in the change in unrealized gain on available for sale securities of $5.6 million which was partially offset by dividends paid of $6.3 million for the three months ended March 31, 2009.

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Both the Board of Governors of the Federal Reserve System, with respect to the Company, and the FDIC, with respect to the Bank, have established certain minimum risk-based capital standards that apply to bank holding companies and federally insured banks. As of March 31, 2009, the Company’s Tier 1 risk-based capital, total risk-based capital and leverage capital ratios were 11.48%, 10.53% and 5.48%, respectively. As of March 31, 2009, the Bank’s risk-based capital ratios were above the levels required for the Bank to be designated as “well capitalized” by the FDIC, with Tier-1 risk-based capital, total risk-based capital and leverage capital ratios of 10.10%, 11.04% and 5.25%, respectively. The Bank is participating in the deposit insurance component of the FDIC Temporary Liquidity Guarantee Program (“TGLP”), which increases deposit insurance on noninterest-bearing transaction account deposits on balances above $250,000 through December 31, 2009. The Company elected to not participate in the U.S. Department of Treasury Capital Purchase Program, which is a part of the Troubled Asset Relief Program.

ITEM 3. QUANTITATIVE AND QUALITATIVE DISCLOSURES ABOUT MARKET RISK

The Company manages market risk, which for the Company is primarily interest rate risk, through its Asset Liability Committee which is composed of senior officers of the Company, in accordance with policies approved by the Company’s Board of Directors.

The Company uses simulation analysis to examine the potential effects of market changes on net interest income and market value. The Company considers macroeconomic variables, Company strategy, liquidity and other factors as it quantifies market risk. See the Company’s Annual Report on Form 10-K, Item 7 “Management’s Discussion and Analysis of Financial Condition and Results of Operations-Interest Rate Sensitivity and Liquidity” which was filed on March 2, 2009 for further discussion.

ITEM 4. CONTROLS AND PROCEDURES

Evaluation of disclosure controls and procedures. As of the end of the period covered by this report, the Company carried out an evaluation, under the supervision and with the participation of its management, including its Chief Executive Officer and Chief Financial Officer, of the effectiveness of the design and operation of its disclosure controls and procedures. In designing and evaluating the disclosure controls and procedures, management recognizes that any controls and procedures, no matter how well designed and operated, can provide only reasonable assurance of achieving the desired control objectives, and management was required to apply judgment in evaluating its controls and procedures. Based on this evaluation, the Company’s Chief Executive Officer and Chief Financial Officer concluded that the Company’s disclosure controls and procedures (as defined in Rules 13a-15(e) and 15d-15(e) under the Securities Exchange Act of 1934, as amended (the “Exchange Act”)) were effective as of the end of the period covered by this report.

Changes in internal control over financial reporting. There were no changes in the Company’s internal control over financial reporting (as such term is defined in Rules 13a-15(f) and 15d-15(f) under the Exchange Act) during the quarter ended March 31, 2009 that have materially affected, or are reasonably likely to materially affect, the Company’s internal control over financial reporting.

PART II – OTHER INFORMATION

ITEM 1. LEGAL PROCEEDINGS

Neither the Company nor the Bank is currently a party to any material legal proceeding.

ITEM 1A. RISK FACTORS

There have been no material changes in the Company’s risk factors from those disclosed in the Company’s Annual Report on Form 10-K for the year ended December 31, 2008.

ITEM 2. UNREGISTERED SALES OF EQUITY SECURITIES AND USE OF PROCEEDS

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ITEM 3. DEFAULTS UPON SENIOR SECURITIES

Not applicable

ITEM 4. SUBMISSION OF MATTERS TO A VOTE OF SECURITY HOLDERS

None.

ITEM 5. OTHER INFORMATION

Not applicable

ITEM 6. EXHIBITS

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SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned thereunto duly authorized.

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Capital Resources

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

The risk-based capital standards issued by the Federal Reserve Board require all bank holding companies to have “Tier 1 capital” of at least 4.0% and “total risk-based” capital (Tier 1 and Tier 2) of at least 8.0% of total risk-weighted tangible assets. “Tier 1 capital” generally includes common shareholders’ equity and qualifying perpetual preferred stock together with related surpluses and retained earnings, less deductions for goodwill and various other intangibles. “Tier 2 capital” may consist of a limited amount of intermediate-term preferred stock, a limited amount of term subordinated debt, certain hybrid capital instruments and other debt securities, perpetual preferred stock not qualifying as Tier 1 capital, and a limited amount of the general valuation allowance for loan losses. The sum of Tier 1 capital and Tier 2 capital is “total risk-based capital.”

The Federal Reserve Board has also adopted guidelines which supplement the risk-based capital guidelines with a minimum ratio of Tier 1 capital to average total consolidated tangible assets, or “leverage ratio,” of 3.0% for institutions with well diversified risk, including no undue interest rate exposure; excellent asset quality; high liquidity; good earnings; and that are generally considered to be strong banking organizations, rated composite 1 under applicable federal guidelines, and that are not experiencing or anticipating significant growth. Other banking organizations are required to maintain a leverage ratio of at least 4.0%. These rules further provide that banking organizations experiencing internal growth or making acquisitions will be expected to maintain capital positions substantially above the minimum supervisory levels and comparable to peer group averages, without significant reliance on intangible assets.

Pursuant to FDICIA, each federal banking agency revised its risk-based capital standards to ensure that those standards take adequate account of interest rate risk, concentration of credit risk and the risks of nontraditional activities, as well as reflect the actual performance and expected risk of loss on multifamily mortgages. The Bank is subject to capital adequacy guidelines of the FDIC that are substantially similar to the Federal Reserve Board’s guidelines. Also pursuant to FDICIA, the FDIC has promulgated regulations setting the levels at which an insured institution such as the Bank would be considered “well-capitalized,” “adequately capitalized,” “undercapitalized,” “significantly undercapitalized” and “critically undercapitalized.” Under the FDIC’s regulations, the Bank is classified “well-capitalized” for purposes of prompt corrective action.

Total shareholders’ equity increased to $1.255 billion at December 31, 2008 compared with $1.127 billion at December 31, 2007, an increase of $127.7 million or 11.3%. This increase was primarily the result of net income of $84.5 million and $56.1 million in Common Stock issued in connection with the 1^st Choice acquisition, partially offset by dividends paid on the Common Stock of $23.4 million. During 2007, shareholders’ equity increased by $463.0 million or 69.7% compared with $664.4 million at December 31, 2006, primarily due to net income of $84.2 million and $389.4 million in Common Stock issued in connection with the TXUI and Navasota acquisitions, partially offset by dividends paid on the Common Stock of $20.3 million.

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The following table provides a comparison of the Company’s and the Bank’s leverage and risk-weighted capital ratios as of December 31, 2008 to the minimum and well-capitalized regulatory standards:

The trust preferred securities issued by the Company’s subsidiary trusts are currently included in the Company’s Tier 1 capital for regulatory purposes. On March 1, 2005, the Federal Reserve Board adopted final rules that continue to allow trust preferred securities to be included in Tier 1 capital, subject to stricter quantitative and qualitative limits. Currently, trust preferred securities and qualifying perpetual preferred stock are limited in the aggregate to no more than 25% of a bank holding company’s core capital elements. The new rule amends the existing limit by providing that restricted core capital elements (including trust preferred securities and qualifying perpetual preferred stock) can be no more than 25% of core capital, net of goodwill and associated deferred tax liability. Because the 25% limit currently is calculated without deducting goodwill, the final rule reduces the amount of trust preferred securities that the Company can include in Tier 1 capital. The amount of such excess trust preferred securities are includable in Tier 2 capital. The new quantitative limits will be fully effective March 31, 2009.

Assuming these final rules were effective at December 31, 2008, all trust preferred securities would count as Tier 1 capital. If applicable, the excess amount of trust preferred securities may be included in Tier 2 capital. Assuming these final rules were effective at December 31, 2008, the Company’s consolidated capital ratios would have been unchanged.

Each of the trusts issuing the trust preferred securities holds junior subordinated debentures the Company issued with a 30-year maturity. The final rules provide that in the last five years before the junior subordinated debentures mature, the associated trust preferred securities will be excluded from Tier 1 capital and included in Tier 2 capital. In addition, the trust preferred securities during this five-year period would be amortized out of Tier 2 capital by one-fifth each year and excluded from Tier 2 capital completely during the year prior to maturity of the debentures.

Capital Resources

Capital Resources

Total shareholders’ equity was $1.23 billion at September 30, 2008 compared with $1.13 billion at December 31, 2007, an increase of $101.7 million or 9.0%. The increase was due primarily to net earnings of $61.8 million, the issuance of common stock in connection with the 1^st Choice acquisition of $56.1 million and the issuance of common stock in connection with the exercise of stock options of $2.5 million, partially offset by dividends paid of $17.0 million for the nine months ended September 30, 2008.

Both the Board of Governors of the Federal Reserve System with respect to the Company, and the Federal Deposit Insurance Corporation (“FDIC”) with respect to the Bank, have established certain minimum risk-based capital standards that apply to bank holding companies and federally insured banks. The following table sets forth the Company’s total risk-based capital, Tier 1 risk-based capital, and Tier 1 to average assets (leverage) ratios as of September 30, 2008:

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As of September 30, 2008, the Bank’s risk-based capital ratios were above the levels required for the Bank to be designated as “well capitalized” by the FDIC. The following table sets forth the Bank’s total risk-based capital, Tier 1 risk-based capital, and Tier 1 to average assets (leverage) capital ratios as of September 30, 2008:

ITEM 3. QUANTITATIVE AND QUALITATIVE DISCLOSURES ABOUT MARKET RISK

The Company manages market risk, which for the Company is primarily interest rate risk, through its Asset Liability Committee which is composed of senior officers of the Company, in accordance with policies approved by the Company’s Board of Directors.

The Company uses simulation analysis to examine the potential effects of market changes on net interest income and market value. The Company considers macroeconomic variables, Company strategy, liquidity and other factors as it quantifies market risk. See the Company’s Annual Report on Form 10-K, Item 7 “Management’s Discussion and Analysis of Financial Condition and Results of Operations-Interest Rate Sensitivity and Liquidity” which was filed on February 29, 2008 for further discussion.

ITEM 4. CONTROLS AND PROCEDURES

Evaluation of disclosure controls and procedures. As of the end of the period covered by this report, the Company carried out an evaluation, under the supervision and with the participation of its management, including its Chief Executive Officer and Chief Financial Officer, of the effectiveness of the design and operation of its disclosure controls and procedures. In designing and evaluating the disclosure controls and procedures, management recognizes that any controls and procedures, no matter how well designed and operated, can provide only reasonable assurance of achieving the desired control objectives, and management was required to apply judgment in evaluating its controls and procedures. Based on this evaluation, the Company’s Chief Executive Officer and Chief Financial Officer concluded that the Company’s disclosure controls and procedures (as defined in Rules 13a-15(e) and 15d-15(e) under the Securities Exchange Act of 1934 (the “Exchange Act”)) were effective as of the end of the period covered by this report.

Changes in internal control over financial reporting. There were no changes in the Company’s internal control over financial reporting (as such term is defined in Rules 13a-15(f) and 15d-15(f) under the Exchange Act) during the quarter ended September 30, 2008 that have materially affected, or are reasonably likely to materially affect, the Company’s internal control over financial reporting.

PART II – OTHER INFORMATION

ITEM 1. LEGAL PROCEEDINGS

Not Applicable

ITEM 1A. RISK FACTORS

Except for the addition of the risk factors described below, there has been no material change in the risk factors previously disclosed under “Item 1A. Risk Factors” of the Company’s 2007 Annual Report on Form 10-K for the year ended December 31, 2007 filed with the Securities and Exchange Commission on February 29, 2008.

Capital Resources

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

The risk-based capital standards issued by the Federal Reserve Board require all bank holding companies to have “Tier 1 capital” of at least 4.0% and “total risk-based” capital (Tier 1 and Tier 2) of at least 8.0% of total risk-weighted tangible assets. “Tier 1 capital” generally includes common shareholders’ equity and qualifying perpetual preferred stock together with related surpluses and retained earnings, less deductions for goodwill and

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Index to Financial Statements

various other intangibles. “Tier 2 capital” may consist of a limited amount of intermediate-term preferred stock, a limited amount of term subordinated debt, certain hybrid capital instruments and other debt securities, perpetual preferred stock not qualifying as Tier 1 capital, and a limited amount of the general valuation allowance for loan losses. The sum of Tier 1 capital and Tier 2 capital is “total risk-based capital.”

The Federal Reserve Board has also adopted guidelines which supplement the risk-based capital guidelines with a minimum ratio of Tier 1 capital to average total consolidated tangible assets, or “leverage ratio,” of 3.0% for institutions with well diversified risk, including no undue interest rate exposure; excellent asset quality; high liquidity; good earnings; and that are generally considered to be strong banking organizations, rated composite 1 under applicable federal guidelines, and that are not experiencing or anticipating significant growth. Other banking organizations are required to maintain a leverage ratio of at least 4.0%. These rules further provide that banking organizations experiencing internal growth or making acquisitions will be expected to maintain capital positions substantially above the minimum supervisory levels and comparable to peer group averages, without significant reliance on intangible assets.

Pursuant to FDICIA, each federal banking agency revised its risk-based capital standards to ensure that those standards take adequate account of interest rate risk, concentration of credit risk and the risks of nontraditional activities, as well as reflect the actual performance and expected risk of loss on multifamily mortgages. The Bank is subject to capital adequacy guidelines of the FDIC that are substantially similar to the Federal Reserve Board’s guidelines. Also pursuant to FDICIA, the FDIC has promulgated regulations setting the levels at which an insured institution such as the Bank would be considered “well-capitalized,” “adequately capitalized,” “undercapitalized,” “significantly undercapitalized” and “critically undercapitalized.” Under the FDIC’s regulations, the Bank is classified “well-capitalized” for purposes of prompt corrective action.

Total shareholders’ equity increased to $1.127 billion at December 31, 2007 compared with $664.4 million at December 31, 2006, an increase of $463.0 million or 69.7%. This increase was primarily the result of net income of $84.2 million and $389.4 million in Common Stock issued in connection with the TXUI and Navasota acquisitions, partially offset by dividends paid on the Common Stock of $20.3 million. During 2006, shareholders’ equity increased by $199.7 million or 43.0% compared with $464.7 million at December 31, 2005, primarily due to net income of $61.7 million and $141.4 million in Common Stock issued in connection with the SNB acquisition, partially offset by dividends paid on the Common Stock of $13.0 million.

The following table provides a comparison of the Company’s and the Bank’s leverage and risk-weighted capital ratios as of December 31, 2007 to the minimum and well-capitalized regulatory standards:

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Index to Financial Statements

The trust preferred securities issued by the Company’s subsidiary trusts are currently included in the Company’s Tier 1 capital for regulatory purposes. On March 1, 2005, the Federal Reserve Board adopted final rules that continue to allow trust preferred securities to be included in Tier 1 capital, subject to stricter quantitative and qualitative limits. Currently, trust preferred securities and qualifying perpetual preferred stock are limited in the aggregate to no more than 25% of a bank holding company’s core capital elements. The new rule amends the existing limit by providing that restricted core capital elements (including trust preferred securities and qualifying perpetual preferred stock) can be no more than 25% of core capital, net of goodwill and associated deferred tax liability. Because the 25% limit currently is calculated without deducting goodwill, the final rule reduces the amount of trust preferred securities that the Company can include in Tier 1 capital. The amount of such excess trust preferred securities are includable in Tier 2 capital. The new quantitative limits will be fully effective March 31, 2009.

Assuming these final rules were effective at December 31, 2007, all trust preferred securities would count as Tier 1 capital. If applicable, the excess amount of trust preferred securities may be included in Tier 2 capital. Assuming these final rules were effective at December 31, 2007, the Company’s consolidated capital ratios would have been unchanged.

Each of the trusts issuing the trust preferred securities holds junior subordinated debentures the Company issued with a 30-year maturity. The final rules provide that in the last five years before the junior subordinated debentures mature, the associated trust preferred securities will be excluded from Tier 1 capital and included in Tier 2 capital. In addition, the trust preferred securities during this five-year period would be amortized out of Tier 2 capital by one-fifth each year and excluded from Tier 2 capital completely during the year prior to maturity of the debentures.

Capital Resources

Total shareholders’ equity was $1.07 billion at March 31, 2007 compared with $664.4 million at December 31, 2006, an increase of $402.2 million or 60.5%. The increase was due primarily to net earnings of $20.2 million and the issuance of common stock in connection with the TXUI acquisition of $383.2 million, partially offset by dividends paid of $4.9 million for the three months ended March 31, 2007.

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Both the Board of Governors of the Federal Reserve System, with respect to the Company, and the Federal Deposit Insurance Corporation (“FDIC”), with respect to the Bank, have established certain minimum risk-based capital standards that apply to bank holding companies and federally insured banks. As of March 31, 2007, the Company’s Tier 1 risk-based capital, total risk-based capital and leverage capital ratios were 11.90%, 12.94% and 8.31%, respectively. As of March 31, 2007, the Bank’s risk-based capital ratios were above the levels required for the Bank to be designated as “well capitalized” by the FDIC, with Tier-1 risk-based capital, total risk-based capital and leverage capital ratios of 10.88%, 11.92% and 7.67%, respectively.

ITEM 3. QUANTITATIVE AND QUALITATIVE DISCLOSURES ABOUT MARKET RISK

The Company manages market risk, which for the Company is primarily interest rate risk, through its Asset Liability Committee which is composed of senior officers of the Company, in accordance with policies approved by the Company’s Board of Directors.

The Company uses simulation analysis to examine the potential effects of market changes on net interest income and market value. The Company considers macroeconomic variables, Company strategy, liquidity and other factors as it quantifies market risk. See the Company’s Annual Report on Form 10-K, Item 7 “Management’s Discussion and Analysis of Financial Condition and Results of Operations-Interest Rate Sensitivity and Liquidity” which was filed on March 1, 2007 for further discussion.

ITEM 4. CONTROLS AND PROCEDURES

Evaluation of disclosure controls and procedures. As of the end of the period covered by this report, the Company carried out an evaluation, under the supervision and with the participation of its management, including its Chief Executive Officer and Chief Financial Officer, of the effectiveness of the design and operation of its disclosure controls and procedures. In designing and evaluating the disclosure controls and procedures, management recognizes that any controls and procedures, no matter how well designed and operated, can provide only reasonable assurance of achieving the desired control objectives, and management was required to apply judgment in evaluating its controls and procedures. Based on this evaluation, the Company’s Chief Executive Officer and Chief Financial Officer concluded that the Company’s disclosure controls and procedures (as defined in Rules 13a-15(e) and 15d-15(e) under the Securities Exchange Act of 1934 (the “Exchange Act”)) were effective as of the end of the period covered by this report.

Changes in internal control over financial reporting. On January 31, 2007, the Company completed the acquisition of TXUI. The Company is in the process of integrating TXUI and continuing its evaluation of internal controls pursuant to the Sarbanes-Oxley Act of 2002. Excluding the TXUI acquisition, there have not been any changes in the Company’s internal control over financial reporting (as such term is defined in Rules 13a-15(f) and 15d-15(f) under the Exchange Act) during the quarter ended March 31, 2007 that have materially affected, or are reasonably likely to materially affect, the Company’s internal control over financial reporting.

PART II – OTHER INFORMATION

ITEM 1. LEGAL PROCEEDINGS

Neither the Company nor the Bank is currently a party to any material legal proceeding.

ITEM 1A. RISK FACTORS

There have been no material changes in the Company’s risk factors from those disclosed in the Company’s Annual Report on Form 10-K for the year ended December 31, 2006.

ITEM 2. UNREGISTERED SALES OF EQUITY SECURITIES AND USE OF PROCEEDS

a. Not applicable

b. Not applicable

c. Not applicable

ITEM 3. DEFAULTS UPON SENIOR SECURITIES

Not applicable

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ITEM 4. SUBMISSION OF MATTERS TO A VOTE OF SECURITY HOLDERS

None.

ITEM 5. OTHER INFORMATION

Not applicable

ITEM 6. EXHIBITS

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned thereunto duly authorized.

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