FORM 4	UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549	OMB APPROVAL
Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).	STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP 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	OMB Number: 3235-0287 Expires: January 31, 2005 Estimated average burden hours per response. . .0.5 Filed By Romeo & Dye's Instant Form 4 Filer www.section16.net

1. Name and Address of Reporting Person* Byrne John Joseph	2. Issuer Name and Ticker or Trading Symbol White Mountains Insurance Group, Ltd. (WTM)		6. Relationship of Reporting Person(s) to Issuer (Check all applicable) X Director                                   X 10% Owner X Officer (give title below)          Other (specify below) Chairman and Chief Executive Officer
(Last)      (First)     (Middle) c/o White Mountains Insurance Group, Ltd. 28 Gates Street	3. I.R.S. Identification Number of Reporting Person, if an entity (voluntary)	4. Statement for Month/Day/Year December 24, 2002
(Street) White River Junction, VT 05001		5. If Amendment, Date of Original (Month/Day/Year)	7. 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. Trans- action Date (Month/ Day/ Year)	2A. Deemed Execution Date, if any (Month/Day/ Year)	3. Trans- action Code (Instr. 8)		4. Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 & 5)			5. Amount of Securities Beneficially Owned Follow- ing Reported Transactions(s) (Instr. 3 & 4)	6. Owner- ship 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	12/24/02	12/24/02	G	V	6,270(1)	D	$319	762,922	D
Common Shares								380,909(2)	I	by Trust
Common Shares (restricted)								25,000	D
Common Shares								2(3)	I	401K

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
* If the form is filed by more than one reporting person, see Instruction 4(b)(v).

Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB control number

FORM 4 (continued) 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. Conver- sion or Exercise Price of Derivative Security

3. Trans- action Date (Month/ Day/ Year)

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

4. Trans- action Code (Instr. 8)

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

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

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

8. Price of Derivative Security (Instr. 5)

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

10. Owner- ship Form of Deriv- ative Security: Direct (D) or Indirect (I) (Instr. 4)

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

Code

V

(A)

(D)

Date Exer-cisable

Expira- tion Date

Title

Amount or Number of Shares

Explanation of Responses:

(1) Gifts to family trusts.
(2) Represents shares held in a Grantor Retained Annuity Trust (the Jack Byrne 2001 Grat No.1) dated May 15, 2001 (the "Trust"). The Reporting Person originally contributed a total of 650,000 shares into the Trust on May 15, 2001. At December 31, 2002, 380,909 shares remain in the Trust following a 2002 mandatory distribution. The remaining shares in the Trust continue to be beneficially owned by Mr. Byrne indirectly.
(3) During the year ended December 31, 2002, the Reporting Person acquired 2 shares of WTM's Common Shares under the OneBeacon Insurance Group 401(k) plan. The information in this report is based on a plan statement dated as of December 31, 2002

By: /s/ John J. Byrne
              
**Signature of Reporting Person January 3, 2003
Date

**Intentional misstatements or omissions of facts constitute Federal Criminal Violations.
See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).

Note: File three copies of this Form, one of which must be manually signed.
          If space is insufficient, See Instruction 6 for procedure.

Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB Number.