# White Mountains Insurance Group Ltd: overview

WTM · NYSE · CIK 776867 · [Financials](/sectors/financials.md) · fiscal year ends Dec 31

Pages: [Overview](/companies/wtm.md) · [Financials](/companies/wtm/financials.md) · [Filings](/companies/wtm/filings.md) · [Insiders](/companies/wtm/insiders.md)

Latest reported revenue: [$844.6m](/filings/0001628280-26-053932.md) for Q2 FY2026, three months to 2026-06-30, from the 10-Q filed Aug 6, 2026 (XBRL us-gaap:Revenues, accession 0001628280-26-053932).

## Last eight quarters

| Line item | Unit | Q3 FY2024 (2024-09-30) | Q4 FY2024 (2024-12-31) | Q1 FY2025 (2025-03-31) | Q2 FY2025 (2025-06-30) | Q3 FY2025 (2025-09-30) | Q4 FY2025 (2025-12-31) | Q1 FY2026 (2026-03-31) | Q2 FY2026 (2026-06-30) |
| --- | --- | ---: | ---: | ---: | ---: | ---: | ---: | ---: | ---: |
| Revenue | $m | [839](/filings/0001628280-25-049910.md) | [358 d](/filings/0001628280-26-012603.md) | [578](/filings/0001628280-26-030935.md) | [689](/filings/0001628280-26-053932.md) | [864](/filings/0001628280-25-049910.md) | [1,604 d](/filings/0001628280-26-012603.md) | [518](/filings/0001628280-26-030935.md) | [845](/filings/0001628280-26-053932.md) |
| Gross margin | % | not reported | not reported | not reported | not reported | not reported | not reported | not reported | not reported |
| Operating margin | % | not reported | not reported | not reported | not reported | not reported | not reported | not reported | not reported |
| Net margin | % | [21.3%](/filings/0001628280-25-049910.md) | [(36.4%) d](/filings/0001628280-26-012603.md) | [5.9%](/filings/0001628280-26-030935.md) | [17.8%](/filings/0001628280-26-053932.md) | [13.2%](/filings/0001628280-25-049910.md) | [52.1% d](/filings/0001628280-26-012603.md) | [(5.3%)](/filings/0001628280-26-030935.md) | [23.6%](/filings/0001628280-26-053932.md) |
| Diluted EPS | $ per share | [69.68](/filings/0001628280-25-049910.md) | not reported | [13.19](/filings/0001628280-26-030935.md) | [47.75](/filings/0001628280-26-053932.md) | [44.18](/filings/0001628280-25-049910.md) | not reported | [(12.59)](/filings/0001628280-26-030935.md) | [80.58](/filings/0001628280-26-053932.md) |
| Free cash flow | $m | not reported | not reported | not reported | not reported | not reported | not reported | not reported | not reported |

- Revenue. XBRL Revenue: us-gaap:Revenues. Derived values: 12-month figure less the 9-month figure.
- Gross margin (gross profit / revenue). XBRL Revenue: us-gaap:Revenues. Derived values: 12-month figure less the 9-month figure.
- Operating margin (operating income / revenue). XBRL Revenue: us-gaap:Revenues. Derived values: 12-month figure less the 9-month figure.
- Net margin (net income / revenue). XBRL Net income: us-gaap:NetIncomeLoss; Revenue: us-gaap:Revenues. Derived values: 12-month figure less the 9-month figure.
- Diluted EPS. XBRL Diluted EPS: us-gaap:EarningsPerShareDiluted.
- Free cash flow (operating cash flow − capital expenditure). XBRL Operating cash flow: us-gaap:NetCashProvidedByUsedInOperatingActivities. Derived values: 9-month figure less the 6-month figure; 12-month figure less the 9-month figure; 6-month figure less the 3-month figure.

## Last five fiscal years

| Line item | Unit | FY2021 (2021-12-31) | FY2022 (2022-12-31) | FY2023 (2023-12-31) | FY2024 (2024-12-31) | FY2025 (2025-12-31) |
| --- | --- | ---: | ---: | ---: | ---: | ---: |
| Revenue | $m | [614](/filings/0000776867-24-000005.md) | [1,158](/filings/0000776867-25-000003.md) | [2,167](/filings/0001628280-26-012603.md) | [2,240](/filings/0001628280-26-012603.md) | [3,735](/filings/0001628280-26-012603.md) |
| Gross margin | % | not reported | not reported | not reported | not reported | not reported |
| Operating margin | % | not reported | not reported | not reported | not reported | not reported |
| Net margin | % | [(44.8%)](/filings/0000776867-24-000005.md) | [68.5%](/filings/0000776867-25-000003.md) | [23.5%](/filings/0001628280-26-012603.md) | [10.3%](/filings/0001628280-26-012603.md) | [29.6%](/filings/0001628280-26-012603.md) |
| Diluted EPS | $ per share | [(89.46)](/filings/0000776867-24-000005.md) | [276.96](/filings/0000776867-25-000003.md) | [198.60](/filings/0001628280-26-012603.md) | [89.79](/filings/0001628280-26-012603.md) | [430.14](/filings/0001628280-26-012603.md) |
| Free cash flow | $m | not reported | not reported | not reported | not reported | not reported |

- Revenue. XBRL Revenue: us-gaap:Revenues.
- Gross margin (gross profit / revenue). XBRL Revenue: us-gaap:Revenues.
- Operating margin (operating income / revenue). XBRL Revenue: us-gaap:Revenues.
- Net margin (net income / revenue). XBRL Net income: us-gaap:NetIncomeLoss; Revenue: us-gaap:Revenues.
- Diluted EPS. XBRL Diluted EPS: us-gaap:EarningsPerShareDiluted.
- Free cash flow (operating cash flow − capital expenditure). XBRL Operating cash flow: us-gaap:NetCashProvidedByUsedInOperatingActivities.

Each value links to the filing it came from. d marks a derived value. A ratio is not reported when any input is missing.

## Insider purchases and sales

The last 20 open-market transactions on Form 4 (codes P and S). Reported price is as stated on the form, not a market price. [All insider transactions](/companies/wtm/insiders.md)

None in coverage.

## Funds that report holding it

From each manager’s latest Form 13F, largest reported value first. Reported value is as filed: filing data, not a price. [All funds](/funds.md)

None of the funds in coverage reports a position in its latest 13F.

## Recent filings

[All 1,093 filings](/companies/wtm/filings.md)

| Filed | Accepted | Form | What it is | Accession |
| --- | --- | --- | --- | --- |
| 2026-08-27 | 08:11 ET | [8-K](/filings/0001628280-26-059191.md) | 5.02 Departure or appointment of officers or directors; 9.01 Financial statements and exhibits | 0001628280-26-059191 |
| 2026-08-06 | 08:50 ET | [10-Q](/filings/0001628280-26-053932.md) | Quarterly report, period 2026-06-30 | 0001628280-26-053932 |
| 2026-08-06 | 08:14 ET | [8-K](/filings/0001628280-26-053913.md) | 2.02 Results of operations; 9.01 Financial statements and exhibits | 0001628280-26-053913 |
| 2026-06-05 | 08:17 ET | [8-K](/filings/0001628280-26-041051.md) | 7.01 Regulation FD disclosure; 9.01 Financial statements and exhibits | 0001628280-26-041051 |
| 2026-05-21 | 16:21 ET | [8-K](/filings/0001628280-26-037284.md) | 5.02 Departure or appointment of officers or directors; 5.07 Shareholder vote results; 9.01 Financial statements and exhibits | 0001628280-26-037284 |
| 2026-05-15 | 09:02 ET | [8-K](/filings/0001628280-26-035349.md) | 1.01 Entry into a material agreement; 2.03 New direct financial obligation; 9.01 Financial statements and exhibits | 0001628280-26-035349 |
| 2026-05-06 | 08:31 ET | [10-Q](/filings/0001628280-26-030935.md) | Quarterly report, period 2026-03-31 | 0001628280-26-030935 |
| 2026-05-06 | 08:20 ET | [8-K](/filings/0001628280-26-030930.md) | 2.02 Results of operations; 9.01 Financial statements and exhibits | 0001628280-26-030930 |
| 2026-05-01 | 17:30 ET | [SCHEDULE 13D/A](/filings/0000950157-26-000566.md) | Ownership report, active investor, amended | 0000950157-26-000566 |
| 2026-04-01 | 16:21 ET | [8-K](/filings/0001628280-26-022818.md) | 8.01 Other events; 9.01 Financial statements and exhibits | 0001628280-26-022818 |

## Latest annual report

[Form 10-K for the fiscal year ended Dec 31, 2025](/filings/0001628280-26-012603.md), filed Feb 27, 2026.

## Forecast league

Q3 FY2026, the quarter ended 2026-09-30, is open for forecasts until the first results filing for it is accepted by EDGAR. Results are due by \[object Promise\]. [Forecast this quarter](/leagues/2026q3/targets/7a34fb90-97a9-4699-88c3-100a3337b1f6)

## About the filer

- CIK: 776867
- Tickers: WTM
- Exchange: NYSE
- SIC code: 6331 Fire, Marine & Casualty Insurance
- State of incorporation: D0
- Filer category: Large accelerated filer

Source: SEC EDGAR, XBRL company facts, the filing index and Forms 4. Last ingested by Listed: Oct 30, 2026, 21:03 ET. No prices; not investment advice.