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UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 10-Q

☒ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

For the period ended September 30, 2025

☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

For the transition period from to

Commission file number 1-8993

WHITE MOUNTAINS INSURANCE GROUP, LTD.

(Exact name of Registrant as specified in its charter)


Bermuda
(State or other jurisdiction of incorporation or organization)						94-2708455
23 South Main Street, Suite 3B						(I.R.S. Employer Identification No.)
Hanover,						03755-2053
New Hampshire						(Zip Code)
(Address of principal executive offices)

Registrant’s telephone number, including area code: (603) 640-2200

Securities registered pursuant to Section 12(b) of the Act:

Title of each class

Trading Symbol(s)

Name of each exchange on which registered

Common Shares, par value $1.00 per share

WTM

New York Stock Exchange

WTM.BH

Bermuda Stock Exchange

Indicate by check mark whether the Registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the Registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days. Yes ý No ☐

Indicate by check mark whether the Registrant has submitted electronically every Interactive Data File required to be submitted pursuant to Rule 405 of Regulation S-T (§232.405 of this chapter) during the preceding 12 months (or for such shorter period that the Registrant was required to submit such files). Yes ý No ☐

Indicate by check mark whether the Registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company, or an emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer”, “smaller reporting company” and “emerging growth company” in Rule 12b-2 of the Exchange Act.

Large accelerated filer

Accelerated filer

☐

Non-accelerated filer

☐

Smaller reporting company

☐

Emerging growth company

☐

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. o

Indicate by check mark whether the Registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act). Yes ☐ No ý

As of November 3, 2025, 2,553,106 common shares with a par value of $1.00 per share were outstanding (which includes 32,910 restricted common shares that were not vested at such date).

WHITE MOUNTAINS INSURANCE GROUP, LTD.

Table of Contents


		Page No.

PART I.	FINANCIAL INFORMATION

Item 1.	Financial Statements (Unaudited)

	Consolidated Balance Sheets, September 30, 2025 and December 31, 2024	1

	Consolidated Statements of Operations , Three and Nine Months Ended September 30, 2025 and 2024	3

	Consolidated Statements of Comprehensive Income, Three and Nine Months Ended September 30, 2025 and 2024	5

	Consolidated Statements of Changes in Equity, Three and Nine Months Ended September 30, 2025 and 2024	6

	Consolidated Statements of Cash Flows, Nine Months Ended September 30, 2025 and 2024	8

	Notes to Consolidated Financial Statements	9

Item 2.	Management’s Discussion and Analysis of Financial Condition and Results of Operations	58

	Results of Operations for the Three and Nine Months Ended September 30, 2025 and 2024	58

	Liquidity and Capital Resources	88

	Non-GAAP Financial Measures	92

	Critical Accounting Estimates	94

	Forward-Looking Statements	94

Item 3.	Quantitative and Qualitative Disclosures About Market Risk	94

Item 4.	Controls and Procedures	95

PART II.	OTHER INFORMATION	95

Items 1 through 6.		95

SIGNATURES		96

Part I.FINANCIAL INFORMATION.

Item 1.Financial Statements

WHITE MOUNTAINS INSURANCE GROUP, LTD.

CONSOLIDATED BALANCE SHEETS

(Unaudited)


Millions, except share and per share amounts	September 30, 2025		December 31, 2024
Assets
P&C Insurance and Reinsurance (Ark/WM Outrigger)
Fixed maturity investments, at fair value	$	1,834.6	$	1,565.1
Common equity securities, at fair value	437.6		425.4
Short-term investments, at fair value	745.4		601.4
Other long-term investments	676.5		547.8
Total investments	3,694.1		3,139.7
Cash (restricted $8.0 and $14.1)	289.9		141.2
Reinsurance recoverables	924.8		589.0
Insurance premiums receivable	1,149.7		768.6
Deferred acquisition costs	281.2		165.2
Goodwill and other intangible assets	292.5		292.5
Other assets	164.6		202.8
Total P&C Insurance and Reinsurance assets	6,796.8		5,299.0
Financial Guarantee (HG Global)
Fixed maturity investments, at fair value	686.5		612.1
Short-term investments, at fair value	56.2		55.5
Total investments	742.7		667.6
Cash	.2		11.5
BAM Surplus Notes, at fair value	396.2		381.7
Insurance premiums receivable	7.7		4.4
Deferred acquisition costs	93.2		86.6

Other assets	26.1		27.6
Total Financial Guarantee assets	1,266.1		1,179.4
Asset Management (Kudu)
Short-term investments, at fair value	24.6		27.9
Other long-term investments	1,214.4		1,014.0
Total investments	1,239.0		1,041.9
Cash	4.8		.6
Accrued investment income	24.2		18.0
Goodwill and other intangible assets	7.7		8.0
Other assets	23.1		39.9
Total Asset Management assets	1,298.8		1,108.4









Specialty Insurance Distribution (Distinguished)
Short-term investments, at fair value	62.6		—
Total investments	62.6		—
Cash (restricted $0.4 and $0.0)	1.5		—
Premiums, commissions and fees receivable	42.2		—
Goodwill and other intangible assets	595.4		—
Other assets	12.0		—
Total Specialty Insurance Distribution assets	713.7		—
Other Operations
Fixed maturity investments, at fair value	159.6		293.7
Common equity securities, at fair value	—		224.6
Investment in MediaAlpha, at fair value	203.2		201.6
Short-term investments, at fair value	199.1		260.1
Other long-term investments	698.3		588.4
Total investments	1,260.2		1,568.4
Cash	41.0		37.6

Goodwill and other intangible assets	154.3		64.8
Other assets	146.5		75.8
Assets held for sale - Bamboo Group	662.0		585.7
Assets held for sale - Other	6.2		6.5
Total Other Operations assets	2,270.2		2,338.8
Total assets	$	12,345.6	$	9,925.6

See Notes to Consolidated Financial Statements.

WHITE MOUNTAINS INSURANCE GROUP, LTD.

CONSOLIDATED BALANCE SHEETS (CONTINUED)

(Unaudited)


Millions, except share and per share amounts	September 30, 2025		December 31, 2024
Liabilities
P&C Insurance and Reinsurance (Ark/WM Outrigger)
Loss and loss adjustment expense reserves	$	2,477.9	$	2,127.5
Unearned insurance premiums	1,427.6		853.3
Debt	159.7		154.5
Reinsurance payable	404.7		149.5
Contingent consideration	229.5		155.3
Other liabilities	249.0		224.7
Total P&C Insurance and Reinsurance liabilities	4,948.4		3,664.8
Financial Guarantee (HG Global)
Unearned insurance premiums	316.3		297.3
Debt	147.7		147.4

Other liabilities	24.5		19.4
Total Financial Guarantee liabilities	488.5		464.1
Asset Management (Kudu)
Debt	274.3		238.6
Other liabilities	85.0		78.1
Total Asset Management liabilities	359.3		316.7







Specialty Insurance Distribution (Distinguished)
Debt	148.7		—
Premiums and commissions payable	67.9		—

Other liabilities	59.4		—
Total Specialty Insurance Distribution liabilities	276.0		—
Other Operations
Loss and loss adjustment expense reserves	14.7		12.1
Unearned insurance premiums	9.5		29.0
Debt	35.4		22.0
Accrued incentive compensation	76.0		79.3
Other liabilities	104.1		33.0
Liabilities held for sale - Bamboo Group	312.3		167.7
Liabilities held for sale - Other	4.3		5.9
Total Other Operations liabilities	556.3		349.0
Total liabilities	6,628.5		4,794.6
Redeemable noncontrolling interests	132.4		—
Equity
White Mountains’s common shareholders’ equity
White Mountains’s common shares at $1 par value per share - authorized 50,000,000 shares; issued and outstanding 2,575,161 and 2,568,148 shares	2.6		2.6
Paid-in surplus	582.0		563.8
Retained earnings	4,183.0		3,919.0
Accumulated other comprehensive income (loss), after-tax:
Net unrealized gains (losses) from foreign currency translation	—		(1.7)
Total White Mountains’s common shareholders’ equity	4,767.6		4,483.7
Nonredeemable noncontrolling interests	817.1		647.3
Total equity	5,584.7		5,131.0
Total liabilities, redeemable noncontrolling interests and equity	$	12,345.6	$	9,925.6

See Notes to Consolidated Financial Statements including Note 13 — “Noncontrolling Interests” and Note 18 — “Commitments and Contingencies”.

WHITE MOUNTAINS INSURANCE GROUP, LTD.

CONSOLIDATED STATEMENTS OF OPERATIONS

(Unaudited)


	Three Months Ended September 30,				Nine Months Ended September 30,
Millions	2025		2024		2025		2024
Revenues:
P&C Insurance and Reinsurance (Ark/WM Outrigger)
Earned insurance premiums	$	542.2	$	552.2	$	1,264.4	$	1,173.3
Net investment income	27.2		24.3		77.0		66.5
Net realized and unrealized investment gains (losses)	17.8		53.2		98.4		84.1
Other revenues	2.3		3.7		10.8		9.6
Total P&C Insurance and Reinsurance revenues	589.5		633.4		1,450.6		1,333.5

Financial Guarantee (HG Global)
Earned insurance premiums	7.5		7.5		22.8		24.3
Net investment income	7.0		6.0		19.8		26.1
Net realized and unrealized investment gains (losses)	7.2		22.5		20.3		8.1
Interest income from BAM Surplus Notes	7.5		7.9		22.5		7.9
Change in fair value of BAM Surplus Notes	—		15.8		—		15.8
Unrealized loss on deconsolidation of BAM	—		(114.5)		—		(114.5)
Other revenues	.1		—		.2		1.1
Total Financial Guarantee revenues	29.3		(54.8)		85.6		(31.2)

Asset Management (Kudu)
Net investment income	18.0		17.2		56.7		50.1
Net realized and unrealized investment gains (losses)	36.1		29.5		80.9		77.5
Other revenues	.3		.5		1.0		.5
Total Asset Management revenues	54.4		47.2		138.6		128.1

P&C Insurance Distribution (Bamboo)
Commission and fee revenues	63.9		42.7		167.2		97.3
Earned insurance premiums	5.2		10.6		21.7		27.0
Other revenues	2.3		2.4		6.4		4.5
Total P&C Insurance Distribution revenues	71.4		55.7		195.3		128.8

Specialty Insurance Distribution (Distinguished)
Commission and fee revenues	14.1		—		14.1		—
Other revenues	.2		—		.2		—
Total Specialty Insurance Distribution revenues	14.3		—		14.3		—

Other Operations
Earned insurance premiums	2.9		11.2		19.1		19.8
Net investment income	6.2		9.6		24.5		27.9
Net realized and unrealized investment gains (losses)	14.9		29.7		49.5		60.4
Net realized and unrealized investment gains (losses) from investment in MediaAlpha	7.7		88.2		1.6		159.7
Commission and fee revenues	4.3		4.1		12.4		11.1
Other revenues	69.3		14.8		139.7		43.7
Total Other Operations revenues	105.3		157.6		246.8		322.6
Total revenues	$	864.2	$	839.1	$	2,131.2	$	1,881.8

See Notes to Consolidated Financial Statements.

WHITE MOUNTAINS INSURANCE GROUP, LTD.

CONSOLIDATED STATEMENTS OF OPERATIONS (CONTINUED)

(Unaudited)


	Three Months Ended September 30,				Nine Months Ended September 30,
Millions	2025		2024		2025		2024
Expenses:
P&C Insurance and Reinsurance (Ark/WM Outrigger)
Loss and loss adjustment expenses	$	254.6	$	288.3	$	652.1	$	644.0
Acquisition expenses	106.8		96.3		287.5		230.8
General and administrative expenses	61.7		68.9		154.1		154.0
Change in fair value of contingent consideration	36.1		34.2		74.2		47.5
Interest expense	4.4		4.9		12.9		15.0
Total P&C Insurance and Reinsurance expenses	463.6		492.6		1,180.8		1,091.3

Financial Guarantee (HG Global)
Acquisition expenses	2.0		1.9		5.9		6.3
General and administrative expenses	1.0		.3		2.6		34.8
Interest expense	4.3		5.8		13.4		13.4
Total Financial Guarantee expenses	7.3		8.0		21.9		54.5

Asset Management (Kudu)
General and administrative expenses	4.7		3.6		12.3		10.5
Interest expense	6.1		5.7		18.6		16.7
Total Asset Management expenses	10.8		9.3		30.9		27.2

P&C Insurance Distribution (Bamboo)
Broker commission expenses	21.5		15.9		56.8		37.9
Loss and loss adjustment expenses	3.3		4.4		15.9		14.5
Acquisition expenses	2.0		3.7		8.0		9.7
General and administrative expenses	26.8		16.2		69.4		43.9
Interest expense	2.8		—		7.8		—
Total P&C Insurance Distribution expenses	56.4		40.2		157.9		106.0

Specialty Insurance Distribution (Distinguished)
Broker commission expenses	5.5		—		5.5		—
General and administrative expenses	10.2		—		10.2		—

Interest expense	1.3		—		1.3		—
Total Specialty Insurance Distribution expenses	17.0		—		17.0		—

Other Operations
Loss and loss adjustment expenses	.6		4.2		18.8		8.1
Acquisition expenses	1.0		4.5		7.0		7.1
Cost of sales	55.3		7.6		105.2		22.2
General and administrative expenses	72.4		32.9		161.7		126.4
Interest expense	1.0		.3		2.3		1.6
Total Other Operations expenses	130.3		49.5		295.0		165.4
Total expenses	685.4		599.6		1,703.5		1,444.4
Pre-tax income (loss)	178.8		239.5		427.7		437.4
Income tax (expense) benefit	(17.1)		(11.6)		(39.6)		(28.9)



Net income (loss)	161.7		227.9		388.1		408.5
Net (income) loss attributable to noncontrolling interests	(47.9)		(48.9)		(117.5)		(47.7)
Net income (loss) attributable to White Mountains’s common shareholders	$	113.8	$	179.0	$	270.6	$	360.8

See Notes to Consolidated Financial Statements.

WHITE MOUNTAINS INSURANCE GROUP, LTD.

CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS)

(Unaudited)


	Three Months Ended September 30,				Nine Months Ended September 30,
Millions, except for per share amounts	2025		2024		2025		2024
Net income (loss) attributable to White Mountains’s common shareholders	$	113.8	$	179.0	$	270.6	$	360.8

Other comprehensive income (loss), net of tax	(.6)		1.3		2.5		1.1


Comprehensive income (loss)	113.2		180.3		273.1		361.9
Other comprehensive (income) loss attributable to noncontrolling interests	.3		(.5)		(.8)		(.5)
Comprehensive income (loss) attributable to White Mountains’s common shareholders	$	113.5	$	179.8	$	272.3	$	361.4


	Three Months Ended September 30,				Nine Months Ended September 30,
	2025		2024		2025		2024
Earnings (loss) per share attributable to White Mountains’s common shareholders:


Basic earnings (loss) per share	$	44.18	$	69.68	$	105.18	$	140.66



Diluted earnings (loss) per share	$	44.18	$	69.68	$	105.18	$	140.66
Dividends declared and paid per White Mountains’s common share	$	—	$	—	$	1.00	$	1.00

See Notes to Consolidated Financial Statements.

WHITE MOUNTAINS INSURANCE GROUP, LTD.

CONSOLIDATED STATEMENTS OF CHANGES IN EQUITY

(Unaudited)


	White Mountains’s Common Shareholders’ Equity
Millions	Common shares and paid-in surplus		Retained earnings		AOCI, after tax		Total		Nonredeemable noncontrolling interest		Total Equity		Redeemable noncontrolling interest
Balances as of June 30, 2025	$	576.6	$	4,067.6	$	.3	$	4,644.5	$	695.7	$	5,340.2	$	—
Net income (loss)	—		113.8		—		113.8		48.7		162.5		(.8)
Other comprehensive income (loss), net of tax	—		—		(.3)		(.3)		(.3)		(.6)		—

Total comprehensive income (loss)	—		113.8		(.3)		113.5		48.4		161.9		(.8)

Dividends to noncontrolling interests	—		—		—		—		(2.1)		(2.1)		—
Issuances of common shares	—		—		—		—		—		—		—



Amortization of restricted share awards	4.9		—		—		4.9		—		4.9		—
Recognition of equity-based compensation expense of subsidiaries	3.2		—		—		3.2		2.1		5.3		—

Net contributions (distributions) and dilution from other noncontrolling interests	(.1)		1.6		—		1.5		(1.8)		(.3)		—

Acquisition of noncontrolling interests	—		—		—		—		74.8		74.8		133.2
Balances as of September 30, 2025	$	584.6	$	4,183.0	$	—	$	4,767.6	$	817.1	$	5,584.7	$	132.4


	White Mountains’s Common Shareholders’ Equity
Millions	Common shares and paid-in surplus		Retained earnings		AOCI, after tax		Total		Nonredeemable noncontrolling interest		Total Equity
Balances as of June 30, 2024	$	561.3	$	3,863.1	$	(1.8)	$	4,422.6	$	449.6	$	4,872.2
Net income (loss)	—		179.0		—		179.0		48.9		227.9
Other comprehensive income (loss), net of tax	—		—		.8		.8		.5		1.3


Total comprehensive income (loss)	—		179.0		.8		179.8		49.4		229.2






Amortization of restricted share awards	4.3		—		—		4.3		—		4.3
Recognition of equity-based compensation expense of subsidiaries	.8		—		—		.8		.2		1.0
Impact to noncontrolling interests for the deconsolidation of BAM	—		—		—		—		153.5		153.5
Net contributions (distributions) and dilution from other noncontrolling interests	(3.1)		6.2		—		3.1		(3.5)		(.4)


Balances as of September 30, 2024	$	563.3	$	4,048.3	$	(1.0)	$	4,610.6	$	649.2	$	5,259.8

See Notes to Consolidated Financial Statements.

WHITE MOUNTAINS INSURANCE GROUP, LTD.

CONSOLIDATED STATEMENTS OF CHANGES IN EQUITY

(Unaudited)


	White Mountains’s Common Shareholders’ Equity
Millions	Common shares and paid-in surplus		Retained earnings		AOCI, after tax		Total		Nonredeemable noncontrolling interest		Total Equity		Redeemable noncontrolling interest
Balances as of January 1, 2025	$	566.4	$	3,919.0	$	(1.7)	$	4,483.7	$	647.3	$	5,131.0	$	—
Net income (loss)	—		270.6		—		270.6		118.3		388.9		(.8)
Other comprehensive income (loss), net of tax	—		—		1.7		1.7		.8		2.5		—

Total comprehensive income (loss)	—		270.6		1.7		272.3		119.1		391.4		(.8)
Dividends declared on common shares	—		(2.6)		—		(2.6)		—		(2.6)		—
Dividends to noncontrolling interests	—		—		—		—		(21.2)		(21.2)		—
Issuances of common shares	2.6		—		—		2.6		—		2.6		—

Repurchases and retirements of common shares	(1.1)		(8.8)		—		(9.9)		—		(9.9)		—
Amortization of restricted share awards	13.6		—		—		13.6		—		13.6		—
Recognition of equity-based compensation expense of subsidiaries	6.5		—		—		6.5		3.4		9.9		—
Net contributions (distributions) and dilution from other noncontrolling interests	(3.4)		4.8		—		1.4		(37.0)		(35.6)		—


Acquisition of noncontrolling interests	—		—		—		—		105.5		105.5		133.2

Balances as of September 30, 2025	$	584.6	$	4,183.0	$	—	$	4,767.6	$	817.1	$	5,584.7	$	132.4


	White Mountains’s Common Shareholders’ Equity
Millions	Common shares and paid-in surplus		Retained earnings		AOCI, after tax		Total		Nonredeemable noncontrolling interest		Total Equity
Balances as of January 1, 2024	$	551.3	$	3,690.8	$	(1.6)	$	4,240.5	$	321.1	$	4,561.6
Net income (loss)	—		360.8		—		360.8		47.7		408.5
Other comprehensive income (loss), net of tax	—		—		.6		.6		.5		1.1


Total comprehensive income (loss)	—		360.8		.6		361.4		48.2		409.6
Dividends declared on common shares	—		(2.5)		—		(2.5)		—		(2.5)
Dividends to noncontrolling interests	—		—		—		—		(9.3)		(9.3)
Issuances of common shares	2.9		—		—		2.9		—		2.9

Repurchases and retirements of common shares	(1.1)		(7.0)		—		(8.1)		—		(8.1)
BAM member surplus contributions, net of tax	—		—		—		—		26.0		26.0
Amortization of restricted share awards	11.8		—		—		11.8		—		11.8
Recognition of equity-based compensation expense of subsidiaries	2.3		—		—		2.3		.8		3.1
Net contributions (distributions) and dilution from other noncontrolling interests	(3.9)		6.2		—		2.3		(2.2)		.1
Impact to noncontrolling interests for the deconsolidation of BAM	—		—		—		—		153.5		153.5
Acquisition of noncontrolling interests — Bamboo	—		—		—		—		111.1		111.1


Balances as of September 30, 2024	$	563.3	$	4,048.3	$	(1.0)	$	4,610.6	$	649.2	$	5,259.8

See Notes to Consolidated Financial Statements.

WHITE MOUNTAINS INSURANCE GROUP, LTD.

CONSOLIDATED STATEMENTS OF CASH FLOWS

(Unaudited)


	Nine Months Ended September 30,
Millions	2025		2024
Cash flows from operations:
Net income (loss)	$	388.1	$	408.5
Adjustments to reconcile net income to net cash provided from (used for) operations:
Net realized and unrealized investment (gains) losses	(249.6)		(230.7)
Net realized and unrealized investment (gains) losses from investment in MediaAlpha	(1.6)		(159.7)
Change in fair value of Ark’s contingent consideration	74.2		47.5
Interest income from BAM Surplus Notes subsequent to deconsolidation, net of interest payments received of $2.4 and $0.0	(20.1)		(7.9)
Change in fair value of BAM Surplus Notes	—		(15.8)
Unrealized loss on deconsolidation of BAM	—		114.5
Deferred income tax expense (benefit)	5.2		3.7
Amortization of restricted share awards	13.6		11.8
Amortization (accretion) and depreciation	2.6		(7.5)
Other operating items:
Net change in reinsurance recoverables	(335.8)		(306.0)
Net change in insurance premiums, commissions and fees receivable	(396.5)		(454.3)
Net change in deferred acquisition costs	(122.6)		(58.2)
Net change in loss and loss adjustment expense reserves	363.7		544.4
Net change in unearned insurance premiums	560.3		458.5
Net change in reinsurance payable	255.2		149.1
Net change in premiums and commissions payable	18.8		44.5
Net change in accrued incentive compensation from Other Operations	(4.0)		(23.2)
Contributions to Kudu’s Participation Contracts	(119.3)		(.2)
Proceeds from Kudu’s Participation Contracts sold	—		9.4
Net other operating activities	64.4		(5.7)


Net cash provided from (used for) operations	496.6		522.7
Cash flows from investing activities:
Net change in short-term investments	(64.4)		610.8
Sales of fixed maturity investments	301.7		320.9
Maturities, calls and paydowns of fixed maturity investments	309.4		323.3
Sales of common equity securities and investment in MediaAlpha	251.0		162.4
Distributions and redemptions of other long-term investments	109.8		169.9




Purchases of consolidated subsidiaries, net of cash acquired of $1.9 and $44.9	(342.2)		(231.8)
Purchases of fixed maturity investments	(759.6)		(1,342.0)
Purchases of common equity securities and investment in MediaAlpha	—		(121.1)
Purchases of other long-term investments	(278.1)		(158.2)
Payments of principal received on the BAM Surplus Notes subsequent to deconsolidation	5.6		—
Impact to cash from deconsolidation of BAM	—		(4.2)
Net other investing activities	14.9		(13.8)


Net cash provided from (used for) investing activities	(451.9)		(283.8)
Cash flows from financing activities:
Draw down of debt and revolving lines of credit	212.4		15.5
Repayment of debt and revolving lines of credit	(5.6)		(36.7)

Cash dividends paid to common shareholders	(2.6)		(2.5)
Repurchases and retirements of common shares	(9.9)		(8.1)

BAM member surplus contributions prior to deconsolidation	—		26.0
Contributions from other noncontrolling interests	1.2		1.0
Distributions to other noncontrolling interests	(60.1)		(12.5)






Net other financing activities	27.7		2.0


Net cash provided from (used for) financing activities	163.1		(15.3)

Net change in cash during the period	207.8		223.6
Cash balance at beginning of period (includes restricted cash balances of $14.1 and $0.7, unrestricted cash held for sale of $16.0 and $0.0 and restricted cash held for sale of $59.5 and $0.0)	266.4		122.4


Cash balance at end of period (includes restricted cash balances of $8.4 and $3.3, unrestricted cash held for sale of $36.6 and $23.9 and restricted cash held for sale of $100.2 and $67.7)	$	474.2	$	346.0
Supplemental cash flows information:
Interest paid	$	(49.2)	$	(46.4)
Net income tax payments	$	(21.3)	$	(19.2)

See Notes to Consolidated Financial Statements.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (Unaudited)

Note 1. Basis of Presentation and Significant Accounting Policies

Basis of Presentation

White Mountains Insurance Group, Ltd. (the “Company” or the “Registrant”) is an exempted Bermuda limited liability company whose principal businesses are conducted through its subsidiaries and other affiliates. The Company’s headquarters is located at 26 Reid Street, Hamilton, Bermuda HM 11, its principal executive office is located at 23 South Main Street, Suite 3B, Hanover, New Hampshire 03755-2053 and its registered office is located at Clarendon House, 2 Church Street, Hamilton, Bermuda HM 11. The Company’s website is www.whitemountains.com. The information contained on White Mountains’s website is not incorporated by reference into, and is not a part of, this report.

The accompanying consolidated financial statements have been prepared in accordance with generally accepted accounting principles in the United States (“GAAP”) and include the accounts of the Company, its subsidiaries and other entities required to be consolidated under GAAP (collectively with the Company, “White Mountains”). Intercompany transactions have been eliminated in consolidation. Certain amounts in the prior period financial statements have been reclassified to conform to the current presentation.

The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities as of the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from those estimates.

These interim financial statements include all adjustments considered necessary by management to fairly state the financial position, results of operations and cash flows of White Mountains. These interim financial statements may not be indicative of financial results for the full year and should be read in conjunction with the Company’s 2024 Annual Report on Form 10-K.

Reportable Segments

As of September 30, 2025, White Mountains conducted its operations through five reportable segments: (1) Ark/WM Outrigger, (2) HG Global, (3) Kudu, (4) Bamboo and (5) Distinguished, with its remaining operating businesses, holding companies and other assets included in Other Operations. White Mountains has made its segment determination based on consideration of the following criteria: (i) the nature of the business activities of each of the Company’s subsidiaries and affiliates; (ii) the manner in which the Company’s subsidiaries and affiliates are organized; (iii) the existence of primary managers responsible for specific subsidiaries and affiliates; and (iv) the organization of information provided to the Company’s chief operating decision makers (“CODMs”) and its Board of Directors. See Note 14 — “Segment Information.”

The Ark/WM Outrigger segment consists of Ark Insurance Holdings Limited and its subsidiaries (collectively, “Ark”) and Outrigger Re Ltd. Segregated Account 2023-1 (“WM Outrigger Re”) (collectively with Ark, “Ark/WM Outrigger”). Ark is a specialty property and casualty insurance and reinsurance company that offers a wide range of niche insurance and reinsurance products, including property, specialty, marine & energy, casualty and accident & health. Ark underwrites select coverages through Lloyd’s Syndicates 4020 and 3902 and Additional Central Settlement Number (“ACSN”) 3832 (collectively, the “Syndicates”) and its wholly-owned subsidiary Group Ark Insurance Limited (“GAIL”). White Mountains acquired a controlling ownership interest in Ark on January 1, 2021 (the “Ark Transaction”). As of September 30, 2025 and December 31, 2024, White Mountains owned 72.1% of Ark on a basic shares outstanding basis (61.9% after taking account of management’s equity incentives). The remaining shares are owned by current and former employees of Ark. In the future, management rollover shareholders could earn additional shares in Ark if and to the extent that White Mountains achieves certain thresholds for its multiple of invested capital (“MOIC”) return. If fully earned, these shares would represent an additional 12.3% of the shares outstanding as of September 30, 2025. The liability related to these additional shares is recorded as contingent consideration. During the fourth quarter of 2022, Ark sponsored the formation of Outrigger Re Ltd., a Bermuda company registered as a special purpose insurer and segregated accounts company, to provide collateralized reinsurance protection on Ark’s Bermuda global property catastrophe excess of loss portfolio for the 2023 underwriting year. Ark renewed its quota share reinsurance agreement with Outrigger Re Ltd. for the 2024 and 2025 underwriting years. White Mountains consolidates the results of its segregated account, WM Outrigger Re, in its financial statements. See Note 2 — “Significant Transactions.” As of September 30, 2025 and December 31, 2024, White Mountains owned 100.0% of WM Outrigger Re’s preferred equity.

The HG Global segment consists of HG Global Ltd. and its wholly-owned subsidiaries (collectively, “HG Global”) and, prior to its deconsolidation on July 1, 2024, the consolidated results of Build America Mutual Assurance Company (“BAM”). See Note 2 — “Significant Transactions.” HG Global was established to fund the startup of BAM and, through its reinsurance subsidiary, HG Re Ltd. (“HG Re”), to provide first-loss reinsurance protection of up to 15%-of-par outstanding for each policy assumed from BAM. HG Global, together with its subsidiaries, funded the initial capitalization of BAM through the purchase of $503.0 million of surplus notes issued by BAM (the “BAM Surplus Notes”). As of September 30, 2025 and December 31, 2024, White Mountains owned 96.9% of HG Global’s preferred equity and 88.4% of its common equity.

White Mountains does not have an ownership interest in BAM. However, through June 30, 2024, White Mountains was required to consolidate BAM’s results in its financial statements because BAM is a variable interest entity (“VIE”) for which White Mountains was the primary beneficiary. BAM’s results were all attributed to noncontrolling interests. On July 1, 2024, HG Re and BAM amended the terms of the first-loss reinsurance treaty (“FLRT”) with respect to certain governance rights held by HG Re. As a result, and in combination with other governance changes at BAM, White Mountains concluded that it no longer has the power to direct BAM’s activities that most significantly impact its economic performance and is no longer BAM’s primary beneficiary. Accordingly, effective July 1, 2024, White Mountains no longer consolidates BAM. Through June 30, 2024, BAM’s results of operations were presented within the HG Global segment. See Note 2 — “Significant Transactions.”

The Kudu segment consists of Kudu Investment Management, LLC and its subsidiaries (collectively, “Kudu”). Kudu provides capital solutions for boutique asset and wealth managers for a variety of purposes including generational ownership transfers, management buyouts, acquisition and growth finance and legacy partner liquidity. Kudu also provides strategic advice to managers from time to time. Kudu’s capital solutions generally are structured as noncontrolling equity interests in the form of revenue and earnings participation contracts (“Participation Contracts”) and designed to generate immediate cash yields. As of September 30, 2025 and December 31, 2024, White Mountains owned 91.2% and 90.4% of Kudu’s basic units outstanding (77.9% and 77.0% on a fully-diluted/fully-converted basis, taking account of management’s equity incentives).

The Bamboo segment consists of PM Holdings LLC (“Bamboo Holdings”), Bamboo Ide8 Insurance Services LLC (“Bamboo MGA”) and Ide8 Re, Inc. (the “Bamboo Captive”) (collectively with Bamboo Holdings and Bamboo MGA, “Bamboo”). Bamboo is a capital-light, tech- and data-enabled insurance distribution platform providing homeowners’ insurance and related products to the residential property market in California. Bamboo operates primarily through Bamboo MGA, its full-service managing general agent (“MGA”) business, where the company manages all aspects of the placement process on behalf of its fronting and reinsurance carrier partners (“Capacity Providers”), including product development, marketing, underwriting, policy issuance and claims oversight, and it earns commissions based on the volume and profitability of the insurance that it places. Bamboo MGA offers both admitted and non-admitted products. Under its capacity agreements, Bamboo MGA’s commission levels are based on a sliding scale tied primarily to its attritional loss ratio. Bamboo also operates two separate but integrated businesses: (i) a retail agency, within Bamboo MGA, offering ancillary products (e.g., flood, earthquake) on behalf of third parties and (ii) the Bamboo Captive, a U.S.-domiciled captive reinsurer that participates in the underwriting risk of Bamboo’s MGA programs to align interests with Capacity Providers. As of September 30, 2025 and December 31, 2024, White Mountains owned 72.8% of Bamboo’s basic units outstanding (63.7% on a fully-diluted/fully-converted basis, taking account of management’s equity incentives).

On October 2, 2025, White Mountains entered into an agreement to sell a controlling financial interest in Bamboo and its parent, WM Pierce Holdings, Inc. (collectively, the “Bamboo Group”). See Note 2 — “Significant Transactions.” As a result, the Bamboo Group’s assets and liabilities have been presented as held for sale in White Mountains’s consolidated balance sheets as of September 30, 2025 and December 31, 2024. See Note 19 — “Held for Sale.”

The Distinguished segment consists of WM Phoenix Holdings L.P. and its subsidiaries d/b/a Distinguished Programs (collectively, “Distinguished”). Distinguished is a full-service MGA and program administrator for specialty property and casualty insurance. Distinguished places insurance across a diversified portfolio of programs broadly grouped into two verticals. The ScaleCo vertical consists of established programs, primarily focused on real estate and hospitality end markets. The GrowthCo vertical consists of start-up programs, focused on a diversified set of specialty property and casualty insurance products across multiple industries. On behalf of its insurance carrier partners, Distinguished typically manages all aspects of the placement process, including product development, marketing, underwriting and policy issuance. Distinguished earns commissions based on the volume and profitability of the insurance that it places. Distinguished does not retain insurance risk. On September 2, 2025, White Mountains acquired a controlling financial interest in Distinguished. See Note 2 — “Significant Transactions.” As of September 30, 2025, White Mountains owned 55.5% of Distinguished on a basic units outstanding basis (43.6% on a fully-diluted/fully-converted basis, taking account of management’s equity incentives).

White Mountains’s other operations consist of the Company and its wholly-owned subsidiary, White Mountains Capital, LLC (“WM Capital”), its other intermediate holding companies, its wholly-owned investment management subsidiary, White Mountains Advisors LLC (“WM Advisors”), investment assets managed by WM Advisors, its interests in MediaAlpha, Inc. (“MediaAlpha”), DavidShield PassportCard Ltd. and its subsidiaries (collectively, “PassportCard/DavidShield”), Elementum Holdings LP (“Elementum”), White Mountains Partners LLC (“WTM Partners”), Enterprise Electric, LLC d/b/a Enterprise Solutions (“Enterprise Solutions”), a Bermuda special purpose collateralized reinsurance vehicle that provides reinsurance capacity to Bamboo (the “Bamboo CRV”), certain other consolidated and unconsolidated entities (“Other Operating Businesses”) and certain other assets (collectively, “Other Operations”). On July 18, 2025, White Mountains deployed $150 million into BroadStreet Partners, Inc. (“BroadStreet”) through a special purpose vehicle (the “BroadStreet SPV”). See Note 2 — “Significant Transactions.” White Mountains’s investment in the BroadStreet SPV is presented within Other Operations.

Significant Accounting Policies

In addition to the following, refer to the Notes to Consolidated Financial Statements in the Company’s 2024 Annual Report on Form 10-K for a complete discussion regarding White Mountains’s significant accounting policies.

Revenue Recognition

Distinguished’s revenues consist primarily of commission and fee revenues related to its placement of insurance policies. Commission revenues are measured based on the contractual rates with its insurance carriers, net of any amounts expected to be uncollectible and any amounts associated with expected policy cancellations and adjustments, and are recognized when contractual performance obligations have been fulfilled. Distinguished also earns fee revenues, primarily related to risk management services provided to certain insureds, which are recognized when contractual performance obligations have been fulfilled. Distinguished’s primary contractual performance obligations are generally satisfied upon the issuance of an insurance policy.

Distinguished’s premiums, commissions and fees receivable consist of insurance premiums and fees receivable from insureds and commissions receivable from insurance carriers, net of a provision for amounts estimated to be uncollectible and any amounts associated with expected policy cancellations and adjustments. Premiums receivable are collected on behalf of Distinguished’s insurance carriers. Distinguished’s premiums and commissions payable consist of insurance premiums payable to insurance carriers and commissions payable to sub-agents and brokers.

Broker Commission Expenses

Distinguished’s broker commission expenses consist of commissions paid to sub-agents and brokers. Broker commission expense is measured in accordance with contractual terms and recognized when incurred, which is generally at the policy issuance date.

Noncontrolling Interests

Noncontrolling interests consist of the ownership interests of noncontrolling shareholders in consolidated entities. White Mountains has both redeemable and nonredeemable noncontrolling interests. Noncontrolling interests with redemption features that are not within White Mountains’s control are classified as redeemable noncontrolling interests, which are considered temporary equity and presented as mezzanine equity on the balance sheet. Redeemable noncontrolling interests are excluded from White Mountains’s total equity. The redeemable noncontrolling interests relate to Distinguished. Noncontrolling interests that do not have any redemption features are classified as nonredeemable noncontrolling interests, which are considered permanent equity and included in White Mountains’s total equity on the balance sheet. Nonredeemable noncontrolling interests are presented separately from White Mountains’s common shareholders’ equity. See Note 13 — “Noncontrolling Interests.”

Comprehensive income (loss) is attributable to both redeemable and nonredeemable noncontrolling interests, which is presented net of related income taxes in the statements of operations and comprehensive income (loss). In addition, White Mountains recognizes an adjustment to the carrying value of the redeemable noncontrolling interests each quarter to the extent the carrying value is below the redemption value, as applicable. The adjustment for redeemable noncontrolling interests is recognized through White Mountains’s common shareholders’ equity. When calculating basic and diluted earnings per share, the adjustment for redeemable noncontrolling interests is treated as being akin to a dividend and presented as adjustment to net income (loss) attributable to White Mountains’s common shareholders.

Note 2. Significant Transactions

Bamboo

On October 2, 2025, White Mountains, together with Bamboo, entered into a securities purchase agreement (the “Bamboo SPA”) with certain affiliates of funds advised by CVC Capital Partners (“CVC”) to sell a controlling financial interest in the Bamboo Group. Under the terms of the Bamboo SPA, White Mountains will sell approximately 77.0% of its equity interest in Bamboo for cash and retain the remainder (the “Bamboo Sale Transaction”). The Bamboo Sale Transaction values Bamboo at an enterprise value of $1.75 billion. White Mountains expects to receive net cash proceeds of approximately $840.0 million and will retain a $250.0 million interest in Bamboo, representing approximately 15.0% on a fully-diluted/fully-converted basis. As a result of the Bamboo Sale Transaction, the Bamboo Group’s assets and liabilities have been presented as held for sale in White Mountains’s consolidated balance sheet as of September 30, 2025. Amounts as of December 31, 2024 have been reclassified to conform to the current period’s presentation. See Note 19 — “Held for Sale.” The Bamboo Sale Transaction is expected to close in the fourth quarter of 2025. Completion of the Bamboo Sale Transaction is subject to the receipt of certain regulatory approvals and other customary closing conditions. There is no condition with respect to the availability of financing to consummate the Bamboo Sale Transaction.

Distinguished

On September 2, 2025, White Mountains acquired a controlling financial interest in Distinguished (the “Distinguished Transaction”). White Mountains funded the Distinguished Transaction through a combination of cash on hand and new borrowings by Distinguished. White Mountains paid $224.3 million of cash consideration, and Distinguished borrowed $50.0 million of incremental debt as part of the transaction. The consideration is subject to customary purchase price adjustments. At closing, White Mountains owned 55.5%, inclusive of its 1.7% previously-held interest, of Distinguished on a basic units outstanding basis (43.6% on a fully-diluted/fully-converted basis, taking account of management’s equity incentives). In connection with the closing, certain management incentive units that would have vested upon a change in control were amended to extend the required service period. As a result, White Mountains’s basic ownership interest at closing increased from the reported 51.0%, which included 1.4% for its previously-held interest, to 55.5%. At closing, 4.2% of the basic units outstanding are owned by Distinguished management (24.7% on a fully-diluted/fully-converted basis). As part of the Distinguished Transaction, WM Phoenix GP, LLC, an indirect wholly-owned subsidiary of the Company, became the general partner of Distinguished. As the general partner, White Mountains has control over all activities of Distinguished subject to consent rights held by certain limited partners. As a result, White Mountains will continue to control Distinguished even if its economic interest falls below 50%. See Note 15 — “Variable Interest Entities.”

On September 5, 2028, the third anniversary of the closing of the Distinguished Transaction, certain noncontrolling unitholders will have the option to sell additional units representing 31.4% of Distinguished’s basic units outstanding to White Mountains at the same unit price paid in the Distinguished Transaction less aggregate per unit distributions. As of September 30, 2025, the redemption value would be $131.2 million if exercised in full. See Note 13 — “Noncontrolling Interests.” In addition, White Mountains will have the parallel option to purchase such units at 1.35 times the unit price paid in the Distinguished Transaction less aggregate per unit distributions.

White Mountains recognized total assets acquired related to the Distinguished Transaction of $726.2 million, including $595.4 million of goodwill and other intangible assets, total liabilities assumed of $231.7 million, including $100.6 million of debt, redeemable noncontrolling interest of $133.2 million and nonredeemable noncontrolling interest of $74.8 million, reflecting provisional acquisition date fair values. In connection with the acquisition, White Mountains incurred transaction costs of $6.8 million in Other Operations.

The Distinguished segment’s revenue and earnings since acquisition are presented in Note 14 — “Segment Information.”

BroadStreet

On July 18, 2025, White Mountains deployed $150.0 million into BroadStreet through the BroadStreet SPV. BroadStreet is an insurance brokerage company with a presence in all 50 U.S. states and ten Canadian provinces. BroadStreet focuses on commercial and personal property & casualty and employee benefits. White Mountains’s unconsolidated limited partnership interest in the BroadStreet SPV is accounted for at fair value using NAV as a practical expedient and is included within other long-term investments. As of September 30, 2025, the fair value of White Mountains’s interest in the BroadStreet SPV was $150.0 million. As of September 30, 2025, White Mountains had a 10.9% limited partnership interest in the BroadStreet SPV and a less than 5% ownership interest in BroadStreet on a look-through basis. See Note 15 — “Variable Interest Entities.”

BAM

On July 1, 2024, HG Re and BAM amended the terms of the FLRT with respect to certain governance rights held by HG Re. As a result, and in combination with other governance changes at BAM, White Mountains concluded that it no longer has the power to direct BAM’s activities that most significantly impact its economic performance and is no longer BAM’s primary beneficiary. Accordingly, effective July 1, 2024, White Mountains no longer consolidates BAM. See Note 15 — “Variable Interest Entities.” Through June 30, 2024, BAM’s results of operations were presented within the HG Global segment.

Upon deconsolidation, the BAM Surplus Notes met the criteria to be accounted for under the fair value option, which White Mountains elected. Accordingly, the BAM Surplus Notes, including accrued interest receivable, were carried at fair value of $387.4 million as of July 1, 2024, which resulted in an unrealized loss on deconsolidation of $114.5 million. This fair value included the impact of a discount for the time value of money, which was previously included in adjusted book value per share as a non-GAAP adjustment to book value per share. See Note 10 — “Municipal Bond Guarantee Reinsurance” for the valuation techniques and inputs utilized to determine the fair value of the BAM Surplus Notes.

WM Outrigger Re

During the fourth quarter of 2022, Ark sponsored the formation of Outrigger Re Ltd., a Bermuda company registered as a special purpose insurer and segregated accounts company, to provide reinsurance capacity to Ark. Outrigger Re Ltd. was initially capitalized with $250.0 million of preference shares for business written in the 2023 underwriting year, of which White Mountains contributed $205.0 million. The remaining capital was provided by third-party investors. Outrigger Re Ltd. entered into collateralized quota share agreements with GAIL to provide reinsurance protection on Ark’s Bermuda global property catastrophe excess of loss portfolio written for the 2023 underwriting year. The proceeds from the issuance of the preference shares were deposited into collateral trust accounts to fund any potential obligations under the reinsurance agreements with GAIL. Outrigger Re Ltd.’s obligations under the reinsurance agreements with GAIL are subject to an aggregate limit equal to the assets in the collateral trusts at any point in time. The terms of the reinsurance agreements are renewable upon the mutual agreement of Ark and the applicable preference shareholder of Outrigger Re Ltd.

During the fourth quarter of 2023, Ark renewed Outrigger Re Ltd. for the 2024 underwriting year with $250.0 million of capital. White Mountains rolled over $130.0 million from its commitment to the 2023 underwriting year and received a return of capital of $75.0 million during 2024 as a result of its reduced capital commitment. The remaining capital was provided by third-party investors.

During the fourth quarter of 2024, Ark renewed Outrigger Re Ltd. for the 2025 underwriting year with $230.0 million of capital. White Mountains’s total commitment was $150.0 million, of which $130.0 million was rolled over from its commitment to the 2024 underwriting year. The remaining capital was provided by third-party investors. The reduced capacity at Outrigger Re Ltd. was replaced by Ark through traditional quota share reinsurance agreements.

White Mountains owns 100% of the preference shares linked to its segregated account, WM Outrigger Re. White Mountains consolidates WM Outrigger Re’s results in its financial statements. WM Outrigger Re’s quota share reinsurance agreement with GAIL eliminates in White Mountains’s consolidated financial statements. See Note 15 — “Variable Interest Entities.”

During the nine months ended September 30, 2025, White Mountains received a distribution of $5.9 million from WM Outrigger Re.

During the three months ended March 31, 2024, White Mountains received a return of capital of $68.1 million from WM Outrigger Re as a result of its reduced capital commitment relating to the 2024 underwriting year. During the three months ended September 30, 2024, White Mountains received an additional $64.9 million from WM Outrigger Re, reflecting an initial profit distribution from the 2023 underwriting year. During 2024, WM Outrigger Re commuted its reinsurance agreement with GAIL for the 2023 underwriting year.

As of September 30, 2025 and December 31, 2024, WM Outrigger Re held investments of $228.4 million and $203.7 million in a collateral trust.

Enterprise Solutions

On April 1, 2025, White Mountains acquired a controlling financial interest in Enterprise Solutions (the “Enterprise Solutions Transaction”). Enterprise Solutions provides specialty electrical contracting services to commercial and institutional customers. White Mountains funded the Enterprise Solutions Transaction through a combination of cash on hand and new borrowings by Enterprise Solutions. White Mountains paid $58.3 million of cash consideration, which included a post-acquisition contribution of $1.5 million, and Enterprise Solutions borrowed $15.0 million in new debt as part of the transaction. At closing, White Mountains owned 65.5% of Enterprise Solutions on a basic units outstanding basis (59.0% on a fully-diluted/fully-converted basis, taking account of management’s equity incentives). This is the first acquisition by WTM Partners.

White Mountains recognized total assets acquired related to Enterprise Solutions of $176.4 million, total liabilities assumed of $74.4 million and noncontrolling interest of $30.6 million, reflecting provisional acquisition date fair values. Total assets acquired included $57.7 million of goodwill and $37.6 million of other intangible assets, reflecting provisional acquisition date fair values. In connection with the acquisition, White Mountains incurred transaction costs of $3.0 million in Other Operations, of which $

WHITE MOUNTAINS INSURANCE GROUP LTD 10-Q