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


FORM 8-K

CURRENT REPORT
Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934

August 26, 2004
Date of Report (Date of earliest event reported)

WHITE MOUNTAINS INSURANCE GROUP, LTD.
(Exact name of registrant as specified in its charter)

Bermuda
(State or other jurisdiction of
incorporation or organization)
  1-8993
(Commission file
number)
  94-2708455
(I.R.S. Employer
Identification No.)


80 South Main Street, Hanover, New Hampshire 03755
(Address of principal executive offices)

(603) 640-2200
(Registrant's telephone number, including area code)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

o  Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

o  Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

o  Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

o  Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))





ITEM 5.02 ELECTION OF DIRECTORS.


ITEM 9.01 FINANCIAL STATEMENTS AND EXHIBITS


EXHIBIT INDEX

99.1
Press Release of White Mountains Insurance Group, Ltd. dated August 26, 2004.


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.

    WHITE MOUNTAINS INSURANCE GROUP, LTD.

DATED: AUGUST 30, 2004

 

By:

/s/  
J. BRIAN PALMER      
J. Brian Palmer
Chief Accounting Officer



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EXHIBIT INDEX
SIGNATURES