UNITED STATES SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549

                                   FORM 10-K/A
                                (Amendment No. 1)

(Mark One)
   |X|         ANNUAL REPORT PRUSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES
               EXCHANGE ACT OF 1934

               For the fiscal year ended December 31, 2006
                                       Or

   |_|         TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE
               SECURITIES ACT OF 1934

               For the transition period from to

                        Commission File Number: 000-50990

                                Tower Group, Inc.
             (Exact name of registrant as specified in its charter)

             Delaware                                      13-3894120
  (State or other jurisdiction of           (I.R.S. Employer Identification No.)
   incorporation or organization)

       120 Broadway, 31st Floor
          New York, New York                                  10271
(Address of principal executive offices)                     (Zip Code)

                                 (212) 655-2000
              (Registrant's telephone number, including area code)

           Securities registered pursuant to Section 12(b) of the Act:
                     Common Stock, $0.0l par value per share


           Securities registered pursuant to Section 12(g) of the Act:
                                      None

     Indicate by check mark if the registrant is a well-known seasoned issuer,
as defined in Rule 405 of Securities Act.
                                                            Yes |_|    No |X|

     Indicate by check mark if the registrant is not required to file reports
pursuant to Section 13 or Section 15(d) of the Act.
                                                            Yes |_|    No |X|

     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 the 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|

     Indicate by check mark whether the registrant is a large accelerated filer,
an accelerated filer, or a non-accelerated filer. See definition of "accelerated
filer and large accelerated filer: in Rule 12b-2 of the Exchange Act. (Check
one):
Large accelerated filer |_|   Accelerated filer |X|   Non-accelerated filer |_|

     Indicate by check mark whether the registrant is a shell company (as
defined in Rule 12b-2 of the Act).                          Yes |_|    No |X|

     The aggregate market value of the registrant's common stock held by
non-affiliates on June 30, 2006 (based on the closing price on the Nasdaq
National Market) on such date was approximately $515,117,298.
     As of March 5, 2007, the registrant had 23,101,108 shares of common stock
outstanding.
                      DOCUMENTS INCORPORATED BY REFERENCE:

<PAGE>


     Part III of this Form 10-K incorporates by reference certain information
from the registrant's definitive Proxy Statement with respect to the
registrant's 2006 Annual Meeting of Shareholders, to be filed not later than 120
days after the close of the registrant's fiscal year (the "Proxy Statement").



<PAGE>


                                EXPLANATORY NOTE


     This Amendment No. 1 to the Annual Report on Form 10-K is being filed
solely to amend Exhibit 31.2 (Certification Pursuant to Section 302 of the
Sarbanes-Oxley Act of 2002) and includes Francis M. Colalucci's conformed
signature. The original certification was signed on the date indicated, but the
filed version did not contain the conformed signature. Unaffected items have not
been repeated in the Amendment No. 1.

     Except as described above, no other changes have been made to the original
Form 10-K, and this form 10-K/A does not amend, update or change the financial
statements or any other items or disclosures in the original Form 10-K. This
Form 10-K/A does not reflect events occurring after the filing of the Form 10-K
or modify or update those disclosures, including any exhibits to the form 10-K
affected by subsequent events. Information not affected by the changes described
above is unchanged and reflects the disclosures made at the time of the original
filing of the Form 10-K on March 8, 2007. Accordingly, this form 10-K/A should
be read in conjunction with our filings made with the Securities and Exchange
commission subsequent to the filing of the original Form 10-K, including any
amendments to those filings.


Item 15. Exhibits, Financial Statement Schedules

          (a) The following documents are filed as part of this report:

          1. Exhibits:

31.2 amended Certification Pursuant to Section 302 of the Sarbanes-Oxley Act of
2002.

<PAGE>


SIGNATURES
     Pursuant to the requirements of Section 13 or 15(d) 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.


                   DATED: MARCH 13, 2007

                   TOWER GROUP, INC.

                   BY:    /S/ MICHAEL H. LEE
                      ----------------------------------------
                   NAME:  MICHAEL H. LEE
                   TITLE: CHAIRMAN OF THE BOARD, PRESIDENT AND
                          CHIEF EXECUTIVE OFFICER

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

        Signature                         Title                        Date
------------------------  --------------------------------------  --------------

  /s/ Michael H. Lee       Chairman of the Board, President and
------------------------           Chief Executive Officer
      Michael H. Lee           (Principal Executive Officer)      March 13, 2007

/s/ Francis M. Colalucci  Senior Vice President, Chief Financial
------------------------      Officer and Treasurer, Director
    Francis M. Colalucci       (Principal Financial Officer,
                               Principal Accounting Officer)      March 13, 2007

   /s/ Steven G. Fauth             Senior Vice President,
------------------------          and Secretary, Director         March 13, 2007
       Steven G. Fauth

 /s/ Steven W. Schuster                  Director                 March 13, 2007
------------------------
     Steven W. Schuster

   /s/ Charles A. Bryan                  Director                 March 13, 2007
------------------------
       Charles A. Bryan

 /s/ William W. Fox Jr.                  Director                 March 13, 2007
------------------------
     William W. Fox Jr.

/s/ Austin P. Young III                  Director                 March 13, 2007
------------------------
    Austin P. Young III