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    <ACCEPTANCE-DATETIME>20200408184915
    ACCESSION NUMBER:		0000776867-20-000015
    CONFORMED SUBMISSION TYPE:	8-K
    PUBLIC DOCUMENT COUNT:		19
    CONFORMED PERIOD OF REPORT:	20200407
    ITEM INFORMATION:		Regulation FD Disclosure
    ITEM INFORMATION:		Financial Statements and Exhibits
    FILED AS OF DATE:		20200409
    DATE AS OF CHANGE:		20200408

    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:		8-K
    		SEC ACT:		1934 Act
    		SEC FILE NUMBER:	001-08993
    		FILM NUMBER:		20782859

    	BUSINESS ADDRESS:
    		STREET 1:		80 SOUTH MAIN ST
    		CITY:			HANOVER
    		STATE:			NH
    		ZIP:			03755
    		BUSINESS PHONE:		603 640 2200

    	MAIL ADDRESS:
    		STREET 1:		80 SOUTH MAIN STREET
    		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
    </SEC-HEADER>
    <DOCUMENT>
    <TYPE>8-K
    <SEQUENCE>1
    <FILENAME>wtm-20200407.htm
    <DESCRIPTION>8-K
    <TEXT>
    Document 1 - file: wtm-20200407.htm

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>EX-99.1
    <SEQUENCE>2
    <FILENAME>exhibit991covid-19letter.htm
    <DESCRIPTION>EX-99.1
    <TEXT>
    Document 2 - file: exhibit991covid-19letter.htm

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    <SEQUENCE>3
    <FILENAME>wtm-20200407.xsd
    <DESCRIPTION>XBRL TAXONOMY EXTENSION SCHEMA DOCUMENT
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    <DOCUMENT>
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    <SEQUENCE>8
    <FILENAME>exhibit991covid-19letter001.jpg
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    <SEQUENCE>9
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    <SEQUENCE>10
    <FILENAME>exhibit991covid-19letter003.jpg
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    <SEQUENCE>11
    <FILENAME>exhibit991covid-19letter004.jpg
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    <SEQUENCE>12
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    <TYPE>XML
    <SEQUENCE>13
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    <TYPE>JSON
    <SEQUENCE>14
    <FILENAME>MetaLinks.json
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    <DOCUMENT>
    <TYPE>XML
    <SEQUENCE>15
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    <TYPE>EXCEL
    <SEQUENCE>19
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    <SEQUENCE>20
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