Summary of FIRST FINANCIAL BANKSHARES INC

ITEM 1.01 Entry into a Material Definitive Agreement
On June 30, 2009, the Company signed the Sixth Amendment to Loan Agreement with The Frost National Bank, dated June 16, 2009. The purpose of the amendment is to add the FDIC special assessment levied against the Company's subsidiary banks during fiscal 2009 to Net Income, as defined in the Loan Agreement, for the sole purpose of calculating the Return on Equity, Return on Assets and Dividend covenants set forth therein for fiscal 2009 only. ITEM 9.01 Financial Statements and Exhibits

   (d) Exhibits

Exhibit Number                                 Description

     10.1         Loan agreement, dated December 31, 2004, between First Financial
                  Bankshares, Inc. and The Frost National Bank (incorporated by
                  reference from Exhibit 10.1 of the Registrant's Form 8-K filed
                  December 31, 2004)

     10.2         First Amendment to Loan Agreement, dated December 28, 2005, between
                  First Financial Bankshares, Inc. and The Frost National Bank
                  (incorporated by reference from Exhibit 10.2 of the Registrant's
                  Form 8-K filed December 30, 2005)

     10.3         Second Amendment to Loan Agreement, dated December 31, 2006, between
                  First Financial Bankshares, Inc. and The Frost National Bank
                  (incorporated by reference from Exhibit 10.3 of the Registrant's
                  Form 8-K filed December 31, 2006)

     10.4         Third Amendment to Loan Agreement, dated December 31, 2007, between
                  First Financial Bankshares, Inc. and The Frost National Bank
                  (incorporated by reference from Exhibit 10.4 of the Registrant's
                  Form 8-K filed December 31, 2007)

     10.5         Fourth Amendment to Loan Agreement, dated July 24, 2008, between
                  First Financial Bankshares, Inc. and The Frost National Bank
                  (incorporated by reference from Exhibit 10.10 of the Registrant's
                  Form 10-Q filed July 25, 2008)

     10.6         Fifth Amendment to Loan Agreement, dated December 19, 2008, between
                  First Financial Bankshares, Inc. and The Frost National Bank
                  (incorporated by reference from Exhibit 10.6 of the Registrant's
                  Form 8-K filed December 23, 2008)

     10.7         Sixth Amendment to Loan Agreement, dated June 16, 2009, signed
                  June 30, 2009, between First Financial Bankshares, Inc. and The Frost
                  National Bank.