SEC FORM 13F-HR

The Securities and Exchange Commission has not necessarily reviewed the information in this filing and has not determined if it is accurate and complete.
The reader should not assume that the information is accurate and complete.

UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
FORM 13F

FORM 13F COVER PAGE

OMB APPROVAL
OMB Number: 3235-0006
Estimated average burden
hours per response: 23.8

Report for the Calendar Year or Quarter Ended: 12-31-2023
Check here if Amendment    Amendment Number:
This Amendment (Check only one.):    is a restatement.
   adds new holdings entries.
Institutional Investment Manager Filing this Report:
Name: WHITE MOUNTAINS INSURANCE GROUP LTD
Address: 23 South Main Street
Suite 3B
Hanover, NH  03755
Form 13F File Number: 028-01681
CRD Number (if applicable):
SEC File Number (if applicable):

The institutional investment manager filing this report and the person by whom it is signed hereby represent that the person signing the report is authorized to submit it, that all information contained herein is true, correct and complete, and that it is understood that all required items, statements, schedules, lists, and tables, are considered integral parts of this form.

Person Signing this Report on Behalf of Reporting Manager:
Name: Michaela J. Hildreth
Title: Managing Director & Chief Accounting Officer
Phone: 603-640-2200
Signature, Place, and Date of Signing:
/s/ Michaela J. Hildreth BostonMA 02-13-2024
[Signature] [City, State] [Date]
Report Type (Check only one.):
X 13F HOLDINGS REPORT. (Check here if all holdings of this reporting manager are reported in this report.)
   13F NOTICE. (Check here if no holdings reported are in this report, and all holdings are reported by other reporting manager(s).)
   13F COMBINATION REPORT. (Check here if a portion of the holdings for this reporting manager are reported in this report and a portion are reported by other reporting manager(s).)
Form 13F Summary Page
Report Summary:
Number of Other Included Managers: 0
Form 13F Information Table Entry Total: 2
Form 13F Information Table Value Total: 392,620,178
(round to nearest dollar)
List of Other Included Managers:
Provide a numbered list of the name(s) and Form 13F file number(s) of all institutional investment managers with respect to which this report is filed, other than the manager filing this report.
[If there are no entries in this list, state “NONE” and omit the column headings and list entries.]
NONE

SEC FORM 13-F Information Table

The Securities and Exchange Commission has not necessarily reviewed the information in this filing and has not determined if it is accurate and complete.
The reader should not assume that the information is accurate and complete.

UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
FORM 13F

FORM 13F INFORMATION TABLE

OMB APPROVAL
OMB Number: 3235-0006
Estimated average burden
hours per response: 23.8

COLUMN 1 COLUMN 2 COLUMN 3 COLUMN 4 COLUMN 5 COLUMN 6 COLUMN 7 COLUMN 8
VALUE SHRS OR SH/ PUT/ INVESTMENT OTHER VOTING AUTHORITY
NAME OF ISSUER TITLE OF CLASS CUSIP FIGI (to the nearest dollar) PRN AMT PRN CALL DISCRETION MANAGER SOLE SHARED NONE
MEDIAALPHA INC CL A 58450V104 BBG00XRTJ7K6 254,853,476 22,856,814 SH   SOLE   22,856,814 0 0
SPDR S&P 500 ETF TR TR UNIT 78462F103 BBG000BDTBL9 137,766,702 289,846 SH   SOLE   289,846 0 0