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ACCESSION NUMBER:		0000776867-21-000006
CONFORMED SUBMISSION TYPE:	10-K/A
PUBLIC DOCUMENT COUNT:		20
CONFORMED PERIOD OF REPORT:	20201231
FILED AS OF DATE:		20210330
DATE AS OF CHANGE:		20210330

FILER:

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			WHITE MOUNTAINS INSURANCE GROUP LTD
		CENTRAL INDEX KEY:			0000776867
		STANDARD INDUSTRIAL CLASSIFICATION:	FIRE, MARINE & CASUALTY INSURANCE [6331]
		IRS NUMBER:				942708455
		STATE OF INCORPORATION:			D0
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		10-K/A
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-08993
		FILM NUMBER:		21786597

	BUSINESS ADDRESS:	
		STREET 1:		23 SOUTH MAIN STREET
		STREET 2:		SUITE 3B
		CITY:			HANOVER
		STATE:			NH
		ZIP:			03755
		BUSINESS PHONE:		603 640 2200

	MAIL ADDRESS:	
		STREET 1:		23 SOUTH MAIN STREET
		STREET 2:		SUITE 3B
		CITY:			HANOVER
		STATE:			NH
		ZIP:			03755

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	WHITE MOUNTAINS INSURANCE GROUP INC
		DATE OF NAME CHANGE:	19990603

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	FUND AMERICAN ENTERPRISES HOLDINGS INC
		DATE OF NAME CHANGE:	19920703

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	FUND AMERICAN COMPANIES INC
		DATE OF NAME CHANGE:	19920701
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