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UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, DC 20549

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FORM 8-K

CURRENT REPORT

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

Date of Report (Date of earliest event reported) APRIL 29, 2003

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)

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ITEM 7. FINANCIAL STATEMENTS AND EXHIBITS.

(c) Exhibits. The following exhibit is filed herewith:

EXHIBIT INDEX

99(a) Press Release of White Mountains Insurance Group, Ltd. dated April 29, 2003.

ITEM 9. REGULATION FD DISCLOSURE.

The following information is furnished pursuant to Item 12, "Disclosure of Results of Operations and Financial Condition" but is being provided under Item 9, "Regulation FD Disclosure" pursuant to SEC Release 33-8216.

On April 29, 2003, White Mountains Insurance Group, Ltd. issued a press release announcing its results for the quarter ended March 31, 2003. The press release is attached hereto as Exhibit 99 (a) to this Form 8-K. Certain information included in the press release represent non-GAAP financial measures (as defined in Regulation G of the Securities and Exchange Commission). Specifically, non-GAAP financial measures disclosed in the press release are the discussion and presentation of fully converted tangible book value per common share and also a reference to an adjusted GAAP combined ratio for Folksamerica for the first quarter of 2002.

White Mountains' management believes that fully converted tangible book value per common share and discussion of the annualized percentage change in the Company's fully converted tangible book value per share represents a better measure of the increase in shareholder value than book value per share because fully converted tangible book value more closely reflects the intrinsic value of the Company. Book value per share is derived by dividing the Company's total GAAP shareholders' equity as of a given date by the number of common shares outstanding as of that date, including the dilutive effects of outstanding options and warrants to acquire common shares. Fully converted tangible book value per share is derived by expanding the book value per share calculation to include (i) the effects of assumed conversion of all convertible securities and (ii) any remaining unamortized goodwill or deferred credits as of the applicable date. A separate schedule is included in Exhibit 99(a) to this Form 8-K which details the calculation of the Company's fully converted tangible book value per common share. As described above, book value per common share can be calculated by excluding the assumed conversion of convertible preference shares to common shares in both the book value per share numerator and the book value per share denominator.

Additionally, the press release includes a statement regarding Folksamerica's 103% GAAP combined ratio for the three months ended March 31, 2002 when adjusted to exclude the effect of a $17.0 million one-time reduction in a recoverable allowance originally established in connection with Folksamerica's 2000 acquisition of PCA Property and Casualty Insurance Company ("PCA"). On an unadjusted basis, the one-time reduction in the allowance served to decrease Folksamerica's GAAP combined ratio by 12 points (to a 91% GAAP combined ratio). The allowance was initially established in 2000 and relates to a recoverable resulting from PCA's claims against the second injury disability trust fund ("second injury fund") in the State of Florida. The Company reduced the allowance in 2002 because the collection experience and financial stability of the second injury fund had improved significantly since the acquisition and the allowance was determined to be unnecessary. The Company did not participate in the second injury fund prior to the acquisition of PCA, nor is such a recoverable allowance likely to occur in the future because the second injury fund was placed into run-off in 1998. Because Folksamerica's unadjusted first quarter 2002 GAAP combined ratio includes this one-time reinsurance recoverable adjustment, management does not believe that it accurately reflects the profitability from operations in the first quarter of 2002.

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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: MAY 6, 2003		By:	/s/  J. BRIAN PALMER       J. Brian Palmer Chief Accounting Officer

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EXHIBIT INDEX
SIGNATURES

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EXHIBIT 99 (A)

CONTACT: David Foy
Tel: 203-453-1681

WHITE MOUNTAINS REPORTS FIRST QUARTER 2003 RESULTS

        HAMILTON, Bermuda (April 29, 2003)—White Mountains Insurance Group, Ltd. ended the first quarter of 2003 with a fully converted tangible book value per share of $267, an annualized increase of 15% (including dividends) from $259 at year-end. The Company's comprehensive net income was $92 million, compared to a comprehensive net loss of $40 million (excluding $660 million of deferred credits brought into income by an accounting change) during the first quarter of 2002.

CEO Ray Barrette said, "We are now firing on all cylinders and our tangible book value is growing nicely. Both OneBeacon and Folksamerica achieved underwriting profits in the quarter and our investment portfolio continued to deliver good returns. Our significant investment in Montpelier Re is also doing well."

A summary of White Mountains' after-tax comprehensive net income follows:

UNDERWRITING RESULTS

A summary of underwriting results at White Mountains' insurance and reinsurance subsidiaries follows:

OneBeacon

OneBeacon's GAAP combined ratio was 97% for the first quarter of 2003 compared to 109% for the first quarter of 2002 and 107% for all of 2002. This includes the full cost of long-term incentive compensation, which amounted to 3 points on the combined ratio in the quarter. Net written premiums were $494 million down from $716 million in the first quarter of 2002. Net written premiums on core operations, which is comprised of personal and commercial lines business in the Northeast and specialty

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business, were $450 million compared to $540 million in the first quarter of 2002. Net written premiums from business in run-off were $44 million, down 75% from $176 million in the first quarter of 2002.

John Cavoores, President of OneBeacon, said, "Our core operations had a 94% GAAP combined ratio in the first quarter. Personal lines, including AutoOne had a strong quarter with a 95% combined ratio. While winter weather was a factor, the result was within our expected catastrophe loads. Commercial lines, which showed improvement from year-end, with a 100% combined ratio, was negatively impacted by the run-off of old workers compensation and general liability policies. We continued to have strong momentum in commercial lines as price increases averaged 15% in the first quarter and new business is up 49% quarter over quarter, with workers compensation representing only 9% of the new business mix. We have also launched a new package policy and system for small businesses starting with New England. Specialty operations had an outstanding quarter with an 86% combined ratio. Specialty now represents nearly 30% of premiums and is growing 24% over 2002".

Folksamerica

Folksamerica's GAAP combined ratio was 95% for the first quarter of 2003 compared to 91% (103% when excluding a one-time reduction in reinsurance recoverable allowance originally established in connection with the PCA Property & Casualty Insurance Company acquisition) in the first quarter last year. Net written premiums for the first quarter of 2003 were $238 million, up 62% from $147 million for the first quarter of 2002.

Steve Fass, CEO of Folksamerica, said, "This was a satisfying quarter with all underwriting units producing positive results. The January renewal season was great. Rates held or increased in nearly all lines, we expanded our participation with many existing clients and added several important new clients. In today's turbulent times insurers, more than ever, appreciate the stability and common sense approach to underwriting that are Folksamerica's hallmarks."

White Mountains Underwriting Ltd. ("WMU")

WMU, White Mountains' underwriting advisors specializing in the placement of international property excess reinsurance, generated advisory fees of $18 million and comprehensive net income of $15 million during the first quarter of 2003, compared to $8 million of advisory fees and $6 million in comprehensive net income during the first quarter of 2002. WMU recommended $59 million in written premiums to Olympus Reinsurance Ltd. in the first quarter of 2003, compared with $29 million during the first quarter of 2002.

Other Insurance and Reinsurance Operations

White Mountains' other insurance and reinsurance operations consist of Esurance, Fund American Re and the International American Group. First quarter 2003 comprehensive net losses were $2 million, compared to $6 million in the first quarter of 2002. The reduction in comprehensive net loss was primarily from improved results at Esurance, which is on track to achieve profitability during 2004.

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INVESTMENT RESULTS

A summary of White Mountains' after-tax investment results follows:

White Mountains' investment results for the first quarter of 2003 included gains from both its fixed maturity and common equity portfolios. Investment losses during the first quarter of 2002 were primarily from unrealized losses in the fixed maturity portfolio resulting from increasing interest rates during the period. The decrease in net investment income from the first quarter of 2002 to the first quarter of 2003 was primarily the result of lower average net invested assets in OneBeacon's investment portfolio as it gradually shrunk with the run-off of OneBeacon's non-core book. Fixed maturity yields were flat quarter over quarter.

        John Gillespie, President of White Mountains Advisors, said, "We continued our strategy of gradually shortening the bond portfolio duration and gradually accumulating value equities in the first quarter."

HOLDING COMPANY AND FINANCING ACTIVITIES

White Mountains recorded after-tax expenses of $31 million for the first quarter of 2003 from holding company activities, mostly financing and purchase accounting charges. This compares with after-tax losses of $33 million for the first quarter of 2002. After-tax interest and other financing charges were $19 million in the first quarter of 2003 compared to $21 million in the first quarter of 2002. Purchase accounting charges related to the OneBeacon acquisition were $6 million in the first quarter of 2003 versus $11 million in the first quarter of 2002.

White Mountains' comprehensive net income for the first quarter of 2002 also included $660 million to recognize the net deferred credit balance in existence at that time as a result of the adoption of new accounting standards on January 1, 2002.

ADDITIONAL INFORMATION

White Mountains is a Bermuda-domiciled financial services holding company traded on the New York Stock Exchange under the symbol WTM. Additional financial information and other items of interest are available at the Company's website located at www.whitemountains.com. The Company expects to file its Form 10-Q with the Securities and Exchange Commission on or before Thursday, May 15, 2003 and urges shareholders to refer to that document for more complete information concerning White Mountains' financial results.

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

The information contained in this earnings 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':

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growth in book value per share or return on equity;



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business strategy;



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financial and operating targets or plans;



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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 our 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 our 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 continued availability of capital and financing;



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general economic, market or business conditions;



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



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competitive forces, including the conduct of other property and casualty insurers and reinsurers



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



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



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loss reserves established subsequently proving to have been inadequate; and



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

        Consequently, all of the forward-looking statements made in this earnings 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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WHITE MOUNTAINS INSURANCE GROUP, LTD.
CONDENSED CONSOLIDATED BALANCE SHEETS

(millions, except share and per share amounts)

			(Unaudited)
			March 31, 2003			December 31, 2002
Assets
Fixed maturity investments, at fair value			$	6,494.4		$	6,669.1
Short-term investments, at fair value				1,937.0			1,790.6
Common equity securities, at fair value				291.1			275.0
Other investments				147.5			164.7
	Total investments			8,870.0			8,899.4
Reinsurance recoverable on unpaid losses				3,865.4			4,071.9
Reinsurance recoverable on paid losses				158.9			159.8
Insurance premiums receivable—currently due				121.8			112.0
Insurance premiums receivable—other				451.4			503.0
Reinsurance premiums receivable				243.7			215.5
Accounts receivable on unsettled investment sales				609.6			160.8
Investments in unconsolidated insurance affiliates				417.0			399.9
Deferred tax asset				397.0			430.0
Deferred acquisition costs				244.5			244.9
Ceded unearned premiums				189.7			163.9
Other assets				569.0			672.5
	Total Assets		$	16,138.0		$	16,033.6
Liabilities
Loss and loss adjustment expense reserves			$	8,552.7		$	8,875.3
Unearned insurance and reinsurance premiums				1,500.9			1,514.4
Accounts payable on unsettled investment purchases				1,061.4			495.2
Debt				781.4			793.2
Funds held under reinsurance treaties				169.8			262.4
Other liabilities				1,172.1			1,285.3
	Total liabilities			13,238.3			13,225.8
Convertible Preference Shares				230.5			219.0
Minority Interest—preferred stock of subsidiaries				184.0			180.9
Common Shareholders' Equity
Common shares and paid-in surplus				1,134.5			1,129.3
Retained earnings				1,154.2			1,071.9
Accumulated other comprehensive income, after tax				196.5			206.7
	Total common shareholders' equity			2,485.2			2,407.9
Total Liabilities, Convertible Preference Shares, Minority Interest and Common Shareholders' Equity			$	16,138.0		$	16,033.6
Common shares outstanding (000's)				8,357	sh		8,351	sh
Common and equivalent shares outstanding (000's)				10,816	sh		10,806	sh
Fully converted book value per common and equivalent share			$	266.96		$	258.82

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WHITE MOUNTAINS INSURANCE GROUP, LTD.
CONDENSED CONSOLIDATED STATEMENTS OF INCOME AND COMPREHENSIVE INCOME

(millions, except per share amounts)

				(Unaudited) Three Months Ended March 31,
				2003			2002
Revenues:
	Earned insurance and reinsurance premiums			$	803.0		$	959.4
	Net investment income				78.6			86.7
	Net realized gains (losses) on investments				58.2			(.1	)
	Other revenue				24.5			40.0
		Total revenues			964.3			1,086.0
Expenses:
	Loss and loss adjustment expenses				522.6			706.4
	Insurance and reinsurance acquisition expenses				157.9			190.7
	General and administrative expenses				110.0			155.8
	Accretion of fair value adjustment to loss and loss adjustment expense reserves				14.2			24.0
	Interest expense				13.6			18.2
		Total expenses			818.3			1,095.1
Pretax income (loss)					146.0			(9.1	)
	Tax benefit (provision)				(46.1	)		13.0
Net income before minority interest, accounting changes and equity in earnings of unconsolidated subsidiaries					99.9			3.9
	Accretion of subsidiary preferred stock to face value				(3.1	)		(2.4	)
	Dividends on subsidiary preferred stock				(7.6	)		(7.6	)
	Equity in earnings of unconsolidated insurance affiliates				12.9			1.0
Net income (loss) from continuing operations					102.1			(5.1	)
	Cumulative effect of changes in accounting principles				-			660.2
Net income					102.1			655.1
	Other comprehensive loss items				(10.2	)		(35.5	)
Comprehensive net income				$	91.9		$	619.6
Computation of net income available to common shareholders:
Net income				$	102.1		$	655.1
	Redemption value adjustment—Convertible Preference Shares				(11.5	)		-
Net income available to common shareholders				$	90.6		$	655.1
Basic earnings per Common Share:
	Net income (loss) from continuing operations			$	10.94		$	(.62	)
	Net income				10.94			80.09
Diluted earnings per Common Share:
	Net income (loss) from continuing operations			$	9.92		$	(.62	)
	Net income				9.92			80.09

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WHITE MOUNTAINS INSURANCE GROUP, LTD.
FULLY CONVERTED TANGIBLE BOOK VALUE PER COMMON AND EQUIVALENT SHARE [1]

(Unaudited)

			(Unaudited)
			March 31, 2003			December 31, 2002
Numerator (in millions):
common shareholders' equity			$	2,485.2		$	2,407.9
proceeds from assumed exercise of outstanding warrants				300.0			300.0
assumed conversion of convertible preference shares to common shares				230.5			219.0
benefits to be received from share obligations under employee benefit plans				7.6			8.8
remaining accretion of preferred stock to face value				(136.0	)		(139.1	)
	Book value per share numerator			2,887.3			2,796.6
Denominator (in shares):
common shares outstanding				8,357,087	sh		8,351,387	sh
shares issuable upon exercise of outstanding warrants				1,724,200			1,714,285
assumed conversion of convertible preference shares to common shares				677,966			677,966
share obligations under employee benefits plans				56,265			61,965
	Book value per share denominator			10,815,518	sh		10,805,603	sh
Fully converted book value per common and equivalent share			$	266.96		$	258.82

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[1]

assumes the conversion of outstanding convertible preference shares to common shareholders' equity.

(end)

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EXHIBIT 99 (A)
WHITE MOUNTAINS REPORTS FIRST QUARTER 2003 RESULTS
UNDERWRITING RESULTS
INVESTMENT RESULTS
HOLDING COMPANY AND FINANCING ACTIVITIES
ADDITIONAL INFORMATION
Safe Harbor Statement under the Private Securities Litigation Reform Act of 1995
WHITE MOUNTAINS INSURANCE GROUP, LTD. CONDENSED CONSOLIDATED BALANCE SHEETS (millions, except share and per share amounts)
WHITE MOUNTAINS INSURANCE GROUP, LTD. CONDENSED CONSOLIDATED STATEMENTS OF INCOME AND COMPREHENSIVE INCOME (millions, except per share amounts)
WHITE MOUNTAINS INSURANCE GROUP, LTD. FULLY CONVERTED TANGIBLE BOOK VALUE PER COMMON AND EQUIVALENT SHARE [1] (Unaudited)