SCHEDULE IV - REINSURANCE

12 Months Ended

Dec. 31, 2024

SEC Schedule, 12-17, Insurance Companies, Reinsurance [Abstract]

SCHEDULE IV - REINSURANCE

WHITE MOUNTAINS INSURANCE GROUP, LTD.

REINSURANCE

Column A	Column B		Column C		Column D		Column E		Column F
$ in Millions Premiums Earned	Gross Amount		Ceded to Other Companies		Assumed from Other Companies		Net Amount		Percentage of Amount Assumed to Net
Year ended:
December 31, 2024
Ark/WM Outrigger	$	1,004.2	$	(504.6)	$	1,088.2	$	1,587.8	68.5	%
HG Global	15.8		—		15.9		31.7		50.2
Bamboo Captive	—		(4.0)		43.4		39.4		110.2
Bamboo CRV	—		—		32.7		32.7		100.0
December 31, 2023
Ark/WM Outrigger	848.1		(364.0)		925.6		1,409.7		65.7
HG Global	28.7		—		2.5		31.2		8.0
December 31, 2022
Ark/WM Outrigger	655.5		(280.8)		668.7		1,043.4		64.1
HG Global	28.6		—		4.7		33.3		14.1

Schedules of the Registrant should be read in conjunction with the Consolidated Financial Statements and Notes.