FORM 4 Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP OF SECURITIES Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934, Section 17(a) of the Public Utility Holding Company Act of 1935 or Section 30(h) of the Investment Company Act of 1940

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(Print or Type Responses)

1. Name and Address of Reporting Person * BERKOWITZ BRUCE R   2. Issuer Name and Ticker or Trading Symbol WHITE MOUNTAINS INSURANCE GROUP LTD [WTM] 5. Relationship of Reporting Person(s) to Issuer (Check all applicable) __X__ Director _____ 10% Owner _____ Officer (give title below) _____ Other (specify below) (Last) (First) (Middle) C/O WHITE MOUNTAINS INSURANCE GROUP, LTD, 80 SOUTH MAIN STREET 3. Date of Earliest Transaction (Month/Day/Year) 11/11/2005 (Street) HANOVER, NH 03755 4. If Amendment, Date Original Filed(Month/Day/Year) 6. Individual or Joint/Group Filing(Check Applicable Line) _X_ Form filed by One Reporting Person ___ Form filed by More than One Reporting Person (City) (State) (Zip) Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned

1.Title of Security (Instr. 3) 2. Transaction Date (Month/Day/Year) 2A. Deemed Execution Date, if any (Month/Day/Year) 3. Transaction Code (Instr. 8) 4. Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5) 5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4) 6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4) 7. Nature of Indirect Beneficial Ownership (Instr. 4) Code V Amount (A) or (D) Price Common Shares 11/11/2005   S   1,000 D $ 625 82,500 I See footnote (1) Common Shares 11/11/2005   S   1,000 D $ 626 81,500 I See footnote (1) Common Shares 11/11/2005   S   500 D $ 626.01 81,000 I See footnote (1) Common Shares 11/11/2005   S   1,000 D $ 626.02 80,000 I See footnote (1) Common Shares 11/11/2005   S   2,600 D $ 627 77,400 I See footnote (1) Common Shares 11/11/2005   S   400 D $ 627.01 77,000 I See footnote (1) Common Shares 11/11/2005   S   500 D $ 628.5 76,500 I See footnote (1) Common Shares 11/11/2005   S   500 D $ 629 76,000 I See footnote (1) Common Shares 11/11/2005   S   500 D $ 630 75,500 I See footnote (1) Common Shares 11/11/2005   S   300 D $ 631.1 75,200 I See footnote (1) Common Shares 11/11/2005   S   500 D $ 631.5 74,700 I See footnote (1) Common Shares 11/11/2005   S   200 D $ 631.6 74,500 I See footnote (1) Common Shares 11/11/2005   S   1,000 D $ 632 73,500 I See footnote (1) Common Shares 11/11/2005   S   700 D $ 633 72,800 I See footnote (1) Common Shares 11/11/2005   S   400 D $ 633.01 72,400 I See footnote (1) Common Shares 11/11/2005   S   900 D $ 633.02 71,500 I See footnote (1) Common Shares 11/11/2005   S   1,000 D $ 633.1 70,500 I See footnote (1)

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Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned
(e.g., puts, calls, warrants, options, convertible securities)

1. Title of Derivative Security (Instr. 3)

2. Conversion or Exercise Price of Derivative Security

3. Transaction Date (Month/Day/Year)

3A. Deemed Execution Date, if any (Month/Day/Year)

4. Transaction Code (Instr. 8)

5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4, and 5)

6. Date Exercisable and Expiration Date (Month/Day/Year)

7. Title and Amount of Underlying Securities (Instr. 3 and 4)

8. Price of Derivative Security (Instr. 5)

9. Number of Derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4)

10. Ownership Form of Derivative Security: Direct (D) or Indirect (I) (Instr. 4)

11. Nature of Indirect Beneficial Ownership (Instr. 4)

Code

V

(A)

(D)

Date Exercisable

Expiration Date

Title

Amount or Number of Shares

Reporting Owners

Reporting Owner Name / Address	Relationships
	Director	10% Owner	Officer	Other
BERKOWITZ BRUCE R C/O WHITE MOUNTAINS INSURANCE GROUP, LTD 80 SOUTH MAIN STREET HANOVER, NH 03755	X

Signatures

Dennis P. Beaulieu, by Power of Attorney		11/14/2005
**Signature of Reporting Person		Date

Explanation of Responses:

*	If the form is filed by more than one reporting person, see Instruction 4(b)(v).
**	Intentional misstatements or omissions of facts constitute Federal Criminal Violations. See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
(1)	Fairholme Partners L.P. ("Fairholme Partners") is the beneficial owner of 62,000 Common Shares of WTM; Fairholme Ventures II, LLC ("Fairholme Ventures") is the beneficial owner of 1,500 Common Shares of WTM; and Fairholme Funds, Inc./The Fairholme Fund (the "Fairholme Fund") is the beneficial owner of 7,000 Common Shares of WTM. Mr. Berkowitz is the Managing Member of the General Partner of Fairholme Partners and Managing Member of the Managing Member of Fairholme Ventures and Managing Member of the Investment Adviser to Fairholme Fund. Mr. Berkowitz disclaims beneficial ownership of the WTM Common Shares owned by Fairholme Partners, Fairholme Ventures and Fairholme Fund except to the extent of his pecuniary interest therein.

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