What is White Mountains Insurance Group's casualty-runoff — 1?

White Mountains Insurance Group (WTM) reported casualty-runoff — 1 of 8.8% in Q4 2025.

How has White Mountains Insurance Group's casualty-runoff — 1 changed year-over-year?

White Mountains Insurance Group's casualty-runoff — 1 decreased by 0.0% year-over-year, from 8.8% to 8.8%.

What does casualty-runoff — 1 mean?

A primary indicator representing the aggregate financial position or a specific key performance driver for the casualty runoff segment. This metric is used to monitor the overall health and capital requirements of the runoff business unit.

White Mountains Insurance Group (WTM) Casualty-Runoff — 1

Screener

Other product segments

Property and Accident & Health

27.4%+15.1%

Specialty

18.2%-5.7%

Marine & Energy

12.1%-6.2%

Casualty-Active

3.8%-13.6%

Similar metrics at other companies

HIPOCasualty Lines — 1

23%—

HGBermuda - Casualty — 1

2%-1.0pp

HGInternational - Casualty — 1

3%0.0pp

FRHCCivil Liability — 1

34%-4.2pp

FRHCLife Insurance — 1

50.8%+33.9pp

FRHCMotor Vehicle — 1

69%+6.8pp

Other financials

Income statement

See full

Revenue$844.6M+22.5%

Gross profit$764.5M+18.2%

Net income$199.5M+62.3%

Balance sheet

See full

Total debt$932.5M+34.2%

Total equity$5.4B+16.0%

Total assets$13.8B+16.4%

Cash flow

See full

Operating cash flow-$55.5M-131%

Valuation

See full

Market cap$5.3B+15.6%

P/E4.7×—

P/S1.4×-0.5×

Profitability

See full

Gross margin94.1%-3.2pp

Net margin29.3%—

Returns & leverage

See full

Return on equity22.4%—

Debt / equity0.2×0.0×

Where this comes from

Reported directly by White Mountains Insurance Group in its filing.

Tagged under the XBRL concept us-gaap:ShortdurationInsuranceContractsHistoricalClaimsDurationYearOne.

The source filing: White Mountains Insurance Group’s 10-K, filed February 27, 2026.

Filed: Feb 27, 2026, 9:21 AM EST
Fiscal year: FY2025
Accession: 0001628280-26-012603

Casualty-Runoff	Casualty-Runoff / Average Annual Percentage Payout of Incurred Loss and LAE by Age, Net of Reinsurance	Casualty-Runoff / Average Annual Percentage Payout of Incurred Loss and LAE by Age, Net of Reinsurance	Casualty-Runoff / Average Annual Percentage Payout of Incurred Loss and LAE by Age, Net of Reinsurance	Casualty-Runoff / Average Annual Percentage Payout of Incurred Loss and LAE by Age, Net of Reinsurance	Average Annual Percentage Payout of Incurred Loss and LAE by Age, Net of Reinsurance	Average Annual Percentage Payout of Incurred Loss and LAE by Age, Net of Reinsurance	Average Annual Percentage Payout of Incurred Loss and LAE by Age, Net of Reinsurance	Average Annual Percentage Payout of Incurred Loss and LAE by Age, Net of Reinsurance	Average Annual Percentage Payout of Incurred Loss and LAE by Age, Net of Reinsurance	Average Annual Percentage Payout of Incurred Loss and LAE by Age, Net of Reinsurance
Years	1	2	3	4	5	6	7	8	9	10
	8.8%	13.9%	15.3%	14.8%	8.5%	6.7%	5.9%	4.2%	3.2%	2.2%

Item 16. Form 10-K Summary.

FAQ

What is White Mountains Insurance Group's casualty-runoff — 1?: White Mountains Insurance Group (WTM) reported casualty-runoff — 1 of 8.8% in Q4 2025.
How has White Mountains Insurance Group's casualty-runoff — 1 changed year-over-year?: White Mountains Insurance Group's casualty-runoff — 1 decreased by 0.0% year-over-year, from 8.8% to 8.8%.
What does casualty-runoff — 1 mean?: A primary indicator representing the aggregate financial position or a specific key performance driver for the casualty runoff segment. This metric is used to monitor the overall health and capital requirements of the runoff business unit.