<PAGE>   1

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                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549

                            ------------------------
                              Amendment No. 1 to
                                   FORM 10-K

              ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE
                 SECURITIES EXCHANGE ACT OF 1934 (FEE REQUIRED)

                  FOR THE FISCAL YEAR ENDED DECEMBER 31, 1996
                         COMMISSION FILE NUMBER 0-13833

                            ------------------------

                         GEORGE MASON BANKSHARES, INC.
             (EXACT NAME OF REGISTRANT AS SPECIFIED IN ITS CHARTER)

<TABLE>
<S>                                           <C>
                   VIRGINIA                                     54-1303470
       (STATE OR OTHER JURISDICTION OF                         (IRS EMPLOYER
        INCORPORATION OR ORGANIZATION)                      IDENTIFICATION NO.)

     11185 MAIN STREET, FAIRFAX, VIRGINIA                          22030
   (ADDRESS OF PRINCIPAL EXECUTIVE OFFICE)                      (ZIP CODE)
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      (REGISTRANT'S TELEPHONE NUMBER, INCLUDING AREA CODE) (703) 352-1100

                            ------------------------

        SECURITIES REGISTERED PURSUANT TO SECTION 12(b) OF THE ACT: NONE

          SECURITIES REGISTERED PURSUANT TO SECTION 12(g) OF THE ACT:

                      $1.11 PAR VALUE COMMON CAPITAL STOCK
                                (TITLE OF CLASS)

                            ------------------------

     Indicate by check mark whether the registrant (1) has filed all reports
required to be filed by Section 13 or 15 (d) of the Securities Exchange Act of
1934 during the preceding 12 months (or for such shorter period that the
registrant was required to file such reports), and (2) has been subject to such
filing requirements for the past 90 days.  Yes X  No  _
     Indicate by check mark if disclosure of delinquent filers pursuant to Item
405 of Regulation S-K is not contained herein, and will not be contained, to the
best of registrant's knowledge, in definitive proxy or information statements
incorporated by reference in part III of this Form 10-K or any amendment to this
Form 10-K [X].
     At March 14, 1997, the aggregate market value of the voting stock of the
registrant held by non-affiliates of the registrant was approximately $91.9
million computed at $21.00 per share. The number of shares outstanding of the
registrant's Common Stock ($1.11 Par Value) was 5.06 million shares at March 14,
1997.

                      DOCUMENTS INCORPORATED BY REFERENCE

1. Annual Report to Shareholders for the year ended December 31, 1996 - Part I,
   II, IV.
2. Proxy Statement furnished to shareholders in connection with the Annual
   Meeting of Shareholders scheduled for May 16, 1997 -- Part III.

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                                   SIGNATURES

     Pursuant to the requirements of Section 13 or 15(d) of the Securities
Exchange Act of 1934, the Company has duly authorized this report to be signed
on its behalf by the undersigned, thereunto duly authorized.

                                          GEORGE MASON BANKSHARES, INC.

Date: March 26, 1997                      By:    /s/ BERNARD H. CLINEBURG
                                            ------------------------------------
                                                    Bernard H. Clineburg
                                               President and Chief Executive
                                                           Officer

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     Pursuant to the requirements of the Securities Exchange Act of 1934, this
report has been signed below by the following persons on behalf of the
registrant and in the capacities and on the dates indicated.

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<CAPTION>
                    SIGNATURE                                   CAPACITY                   DATE
--------------------------------------------------   ------------------------------   ---------------
<S>                                                  <C>                              <C>
             /s/ BERNARD H. CLINEBURG                Director, President and Chief     March 26, 1997
--------------------------------------------------    Executive Officer (Principal
               Bernard H. Clineburg                        Executive Officer)
                 /s/ ALAN L. BOX                                Director               March 26, 1997
--------------------------------------------------
                   Alan L. Box

               /s/ WILLIAM G. BUCK                              Director               March 26, 1997
--------------------------------------------------
                 William G. Buck

           /s/ RANDOLPH W. CHURCH, JR.                          Director               March 26, 1997
--------------------------------------------------
             Randolph W. Church, Jr.

             /s/ C. BARRIE COOK, M.D.                           Director               March 26, 1997
--------------------------------------------------
               C. Barrie Cook, M.D.

           /s/ ELIZABETH CARLSON DAHLIN                         Director               March 26, 1997
--------------------------------------------------
             Elizabeth Carlson Dahlin

               /s/ EDWARD S. DeBOLT                             Director               March 26, 1997
--------------------------------------------------
                 Edward S. DeBolt

               /s/ LAWRENCE K. DOLL                             Director               March 26, 1997
--------------------------------------------------
                 Lawrence K. Doll

              /s/ WILLIAM H. GORDON                             Director               March 26, 1997
--------------------------------------------------
                William H. Gordon

              /s/ MARSHALL H. GROOM                             Director               March 26, 1997
--------------------------------------------------
                Marshall H. Groom

               /s/ WEBB C. HAYES IV                             Director               March 26, 1997
--------------------------------------------------
                 Webb C. Hayes IV

               /s/ WILLIAM A. HAZEL                             Director               March 26, 1997
--------------------------------------------------
                 William A. Hazel

             /s/ BARNARD F. JENNINGS                            Director               March 26, 1997
--------------------------------------------------
               Barnard F. Jennings

                 /s/ PAUL E. KYLE                               Director               March 26, 1997
--------------------------------------------------
                   Paul E. Kyle

               /s/ JOHN M. McMAHON                              Director               March 26, 1997
--------------------------------------------------
                 John M. McMahon

                /s/ E. A. PRICHARD                              Director               March 26, 1997
--------------------------------------------------
                  E. A. Prichard

            /s/ JAMES J. CONSAGRA, JR.               Treasurer (Principal Financial    March 26, 1997
--------------------------------------------------      and Accounting Officer)
              James J. Consagra, Jr.
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