8-K

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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.

(d)

White Mountains Insurance Group, Ltd. issued a press release announcing the election of Edith E. Holiday on August 26, 2004 to the Board of Directors. The press release furnished herewith is attached as Exhibit 99.1 to this Form 8-K.

ITEM 9.01 FINANCIAL STATEMENTS AND EXHIBITS

(c)

Exhibits. The following exhibit is furnished herewith:

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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ITEM 5.02 ELECTION OF DIRECTORS.
ITEM 9.01 FINANCIAL STATEMENTS AND EXHIBITS

EXHIBIT INDEX
SIGNATURES

EX-99.1

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Exhibit 99.1

EDITH HOLIDAY ELECTED TO WHITE MOUNTAINS' BOARD

HAMILTON, Bermuda (August 26, 2004)—The Board of Directors of White Mountains Insurance Group, Ltd. (NYSE: WTM) today elected Edith Holiday as a Director of the Company.

Ms. Holiday was formerly Assistant to the President of the United States and Secretary of the Cabinet, where she was the primary White House liaison with the Cabinet and all federal agencies, and General Counsel to the United States Treasury. Ms. Holiday is the recipient of the Secretary of the Treasury's highest award, the Alexander Hamilton Award. She currently serves as a director of a number of public companies.

CEO Ray Barrette said, "We are pleased to welcome Ede to our Board. She is a thoughtful and experienced director who has extensive board experience with solid companies. In addition, her Washington experience is a welcomed addition to our Company."

Additional Information

White Mountains is a Bermuda-domiciled financial services holding company traded on the New York Stock Exchange and the Bermuda Stock Exchange under the symbol WTM. Additional financial information and other items of interest are available at the Company's web site located at http://www.whitemountains.com.

Safe Harbor Statement under the Private Securities Litigation Reform Act of 1995

This press release may contain "forward-looking statements" within the meaning of Section 27A of the Securities Act of 1933 and Section 21E of the Securities Exchange Act of 1934. All statements, other than statements of historical facts, included or referenced in this release which address activities, events or developments which we expect or anticipate will or may occur in the future are forward-looking statements. The words "believe," "intend," "expect," "anticipate," "project," "estimate," "predict" and similar expressions are also intended to identify forward-looking statements. These forward-looking statements include, among others, statements with respect to White Mountains':

•

growth in book value per share or return on equity;

•

business strategy;

•

financial and operating targets or plans;

•

incurred losses and the adequacy of its loss and loss adjustment expense reserves;

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projections of revenues, income (or loss), earnings (or loss) per share, dividends, market share or other financial forecasts;

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expansion and growth of its business and operations; and

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future capital expenditures.

These statements are based on certain assumptions and analyses made by White Mountains in light of its experience and perception of historical trends, current conditions and expected future developments, as well as other factors believed to be appropriate in the circumstances. However, whether actual results and developments will conform with its expectations and predictions is subject to a number of risks and uncertainties that could cause actual results to differ materially from expectations, including:

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the failure of announced acquisitions to enhance shareholder value;

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claims arising from catastrophic events, such as hurricanes, earthquakes, floods or terrorist attacks;

•

the continued availability of capital and financing;

•

general economic, market or business conditions;

•

business opportunities (or lack thereof) that may be presented to it and pursued;

•

competitive forces, including the conduct of other insurers and reinsurers;

•

changes in domestic or foreign laws or regulations applicable to White Mountains, its competitors or its clients;

•

an economic downturn or other economic conditions adversely affecting its financial position;

•

loss reserves established subsequently proving to have been inadequate; and

•

other factors, most of which are beyond White Mountains' control.

Consequently, all of the forward-looking statements made in this press release are qualified by these cautionary statements, and there can be no assurance that the actual results or developments anticipated by White Mountains will be realized or, even if substantially realized, that they will have the expected consequences to, or effects on, White Mountains or its business or operations. White Mountains assumes no obligation to update publicly any such forward-looking statements, whether as a result of new information, future events or otherwise.

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EDITH HOLIDAY ELECTED TO WHITE MOUNTAINS' BOARD