White Mountains Insurance Group Ltd SEC filings WTM
White Mountains Insurance Group Ltd has 1,005 filings in SEC EDGAR's recent list, going back to Mar 29, 2010. Its latest annual report, Form ARS, was filed on Apr 1, 2026 for the period ended Dec 31, 2025. The latest quarterly report (Form 10-Q) was filed on Nov 5, 2026, covering the quarter ended Sep 30, 2026. The most recent current report (Form 8-K) was filed on Nov 5, 2026 (results of operations). The company's fiscal year ends on December 31.
| Form | Description | Filed | Period |
|---|---|---|---|
| 10-Q | Quarterly report | Nov 5, 2026 | Sep 30, 2026 |
| 8-K |
Current report
Results of operations
|
Nov 5, 2026 | Nov 5, 2026 |
| 8-K |
Current report
Officer or director change
|
Aug 27, 2026 | Aug 26, 2026 |
| N-PX | Filing | Aug 26, 2026 | Jun 30, 2026 |
| 10-Q | Quarterly report | Aug 6, 2026 | Jun 30, 2026 |
| 8-K |
Current report
Results of operations
|
Aug 6, 2026 | Aug 6, 2026 |
| 11-K | Employee savings plan report | Jun 30, 2026 | Dec 31, 2025 |
| 8-K |
Current report
Regulation FD disclosure
|
Jun 5, 2026 | Jun 5, 2026 |
| 8-K |
Current report
Officer or director change, Shareholder vote results
|
May 21, 2026 | May 21, 2026 |
| 8-K |
Current report
Material agreement, New debt
|
May 15, 2026 | May 14, 2026 |
| 10-Q | Quarterly report | May 6, 2026 | Mar 31, 2026 |
| 8-K |
Current report
Results of operations
|
May 6, 2026 | May 6, 2026 |
| 8-K |
Current report
Other events
|
Apr 1, 2026 | Apr 1, 2026 |
| ARS | Annual report to shareholders | Apr 1, 2026 | Dec 31, 2025 |
| DEF 14A | Proxy statement | Apr 1, 2026 | May 21, 2026 |
| 10-K | Annual report | Feb 27, 2026 | Dec 31, 2025 |
| 8-K |
Current report
Other events
|
Feb 26, 2026 | Feb 26, 2026 |
| 8-K |
Current report
Results of operations
|
Feb 6, 2026 | Feb 6, 2026 |
| 8-K |
Current report
Other events
|
Jan 7, 2026 | Jan 7, 2026 |
| SC TO-I/A | Filing | Dec 29, 2025 | — |
| SC TO-I/A | Filing | Dec 22, 2025 | — |
| 8-K |
Current report
Acquisition or sale of assets, Other events
|
Dec 8, 2025 | Dec 5, 2025 |
| SC TO-I | Filing | Nov 21, 2025 | — |
| 10-Q | Quarterly report | Nov 6, 2025 | Sep 30, 2025 |
| 8-K |
Current report
Results of operations
|
Nov 6, 2025 | Nov 6, 2025 |
| 8-K |
Current report
Material agreement
|
Oct 3, 2025 | Oct 2, 2025 |
| 8-K |
Current report
Other events
|
Sep 3, 2025 | Sep 2, 2025 |
| 8-K |
Current report
Officer or director change
|
Sep 2, 2025 | Sep 2, 2025 |
| N-PX | Filing | Aug 27, 2025 | Jun 30, 2025 |
| 10-Q | Quarterly report | Aug 7, 2025 | Jun 30, 2025 |
| 8-K |
Current report
Results of operations
|
Aug 7, 2025 | Aug 7, 2025 |
| 8-K |
Current report
Other events
|
Jul 18, 2025 | Jul 18, 2025 |
| 8-K |
Current report
Other events
|
Jul 16, 2025 | Jul 16, 2025 |
| 11-K | Employee savings plan report | Jul 7, 2025 | Dec 31, 2024 |
| 8-K |
Current report
Material agreement
|
Jul 7, 2025 | Jul 4, 2025 |
| 8-K |
Current report
Regulation FD disclosure
|
Jun 6, 2025 | Jun 6, 2025 |
| 8-K |
Current report
Shareholder vote results
|
May 22, 2025 | May 22, 2025 |
| 10-Q | Quarterly report | May 7, 2025 | Mar 31, 2025 |
| 8-K |
Current report
Results of operations
|
May 7, 2025 | May 7, 2025 |
| 8-K |
Current report
Other events
|
Apr 10, 2025 | Apr 10, 2025 |
| ARS | Annual report to shareholders | Apr 2, 2025 | Dec 31, 2024 |
| DEF 14A | Proxy statement | Apr 2, 2025 | May 22, 2025 |
| 10-K | Annual report | Feb 28, 2025 | Dec 31, 2024 |
| 8-K |
Current report
Results of operations
|
Feb 7, 2025 | Feb 7, 2025 |
| 8-K |
Current report
Other events
|
Jan 8, 2025 | Jan 8, 2025 |
| 10-Q | Quarterly report | Nov 6, 2024 | Sep 30, 2024 |
| 8-K |
Current report
Results of operations
|
Nov 6, 2024 | Nov 6, 2024 |
| N-PX | Filing | Aug 29, 2024 | Jun 30, 2024 |
| 10-Q | Quarterly report | Aug 7, 2024 | Jun 30, 2024 |
| 8-K |
Current report
Results of operations
|
Aug 7, 2024 | Aug 7, 2024 |
| 8-K |
Current report
Regulation FD disclosure
|
Jun 7, 2024 | Jun 7, 2024 |
| 11-K | Employee savings plan report | May 31, 2024 | Dec 31, 2023 |
| 8-K |
Current report
Shareholder vote results
|
May 23, 2024 | May 23, 2024 |
| 10-Q | Quarterly report | May 9, 2024 | Mar 31, 2024 |
| 8-K |
Current report
Results of operations
|
May 9, 2024 | May 9, 2024 |
| 8-K |
Current report
Officer or director change
|
Apr 10, 2024 | Apr 10, 2024 |
| ARS | Annual report to shareholders | Apr 4, 2024 | Dec 31, 2023 |
| DEF 14A | Proxy statement | Apr 4, 2024 | May 23, 2024 |
| 10-K | Annual report | Feb 26, 2024 | Dec 31, 2023 |
| 8-K |
Current report
Officer or director change
|
Feb 23, 2024 | Feb 22, 2024 |
| 8-K |
Current report
Results of operations
|
Feb 7, 2024 | Feb 7, 2024 |
| 8-K |
Current report
Other events
|
Jan 3, 2024 | Jan 2, 2024 |
| 8-K |
Current report
Other events
|
Dec 21, 2023 | Dec 21, 2023 |
| 10-Q | Quarterly report | Nov 6, 2023 | Sep 30, 2023 |
| 8-K |
Current report
Results of operations
|
Nov 6, 2023 | Nov 6, 2023 |
| 8-K |
Current report
Material agreement
|
Oct 20, 2023 | Oct 19, 2023 |
| 10-Q | Quarterly report | Aug 7, 2023 | Jun 30, 2023 |
| 8-K |
Current report
Results of operations
|
Aug 7, 2023 | Aug 7, 2023 |
| SC TO-T/A | Filing | Jun 30, 2023 | — |
| SC TO-T/A | Filing | Jun 27, 2023 | — |
| 11-K | Employee savings plan report | Jun 15, 2023 | Dec 31, 2022 |
| 8-K |
Current report
Regulation FD disclosure
|
Jun 6, 2023 | Jun 6, 2023 |
| SC TO-T | Filing | May 26, 2023 | — |
| 8-K |
Current report
Shareholder vote results
|
May 25, 2023 | May 25, 2023 |
| 8-K |
Current report
Officer or director change
|
May 25, 2023 | May 25, 2023 |
| DEFA14A | Additional proxy material | May 10, 2023 | — |
| 10-Q | Quarterly report | May 9, 2023 | Mar 31, 2023 |
| 8-K |
Current report
Results of operations
|
May 9, 2023 | May 9, 2023 |
| DEFR14A | Filing | Apr 6, 2023 | — |
| ARS | Annual report to shareholders | Apr 5, 2023 | Dec 31, 2022 |
| DEF 14A | Proxy statement | Apr 5, 2023 | — |
| 10-K | Annual report | Feb 27, 2023 | Dec 31, 2022 |
| 8-K |
Current report
Officer or director change
|
Feb 23, 2023 | Feb 22, 2023 |
| 8-K |
Current report
Results of operations
|
Feb 7, 2023 | Feb 7, 2023 |
| 8-K |
Current report
Other events
|
Dec 21, 2022 | Dec 21, 2022 |
| 10-Q | Quarterly report | Nov 7, 2022 | Sep 30, 2022 |
| 8-K |
Current report
Results of operations
|
Nov 7, 2022 | Nov 7, 2022 |
| SC TO-I/A | Filing | Sep 26, 2022 | — |
| SC TO-I/A | Filing | Sep 21, 2022 | — |
| SC TO-I/A | Filing | Aug 30, 2022 | — |
| SC TO-I | Filing | Aug 22, 2022 | — |
| 8-K |
Current report
Results of operations
|
Aug 8, 2022 | Aug 8, 2022 |
| 10-Q | Quarterly report | Aug 8, 2022 | Jun 30, 2022 |
| 8-K |
Current report
Acquisition or sale of assets, Other events
|
Aug 5, 2022 | Aug 1, 2022 |
| 11-K | Employee savings plan report | Jun 14, 2022 | Dec 31, 2021 |
| 8-K |
Current report
Regulation FD disclosure
|
Jun 10, 2022 | Jun 10, 2022 |
| 8-K |
Current report
Shareholder vote results
|
May 26, 2022 | May 26, 2022 |
| 8-K |
Current report
Other events
|
May 26, 2022 | May 26, 2022 |
| DEFA14A | Additional proxy material | May 16, 2022 | — |
| 8-K |
Current report
Material agreement
|
May 10, 2022 | May 9, 2022 |
| 10-Q | Quarterly report | May 6, 2022 | Mar 31, 2022 |
| 8-K |
Current report
Results of operations
|
May 6, 2022 | May 6, 2022 |
| DEF 14A | Proxy statement | Apr 6, 2022 | May 26, 2022 |
| 8-K |
Current report
Other events
|
Apr 1, 2022 | Mar 31, 2022 |
| 10-K | Annual report | Feb 28, 2022 | Dec 31, 2021 |
| 8-K |
Current report
Results of operations
|
Feb 8, 2022 | Feb 8, 2022 |
| 8-K |
Current report
Officer or director change
|
Dec 2, 2021 | Nov 29, 2021 |
| 10-Q | Quarterly report | Nov 8, 2021 | Sep 30, 2021 |
| 8-K |
Current report
Results of operations
|
Nov 8, 2021 | Nov 8, 2021 |
| 8-K |
Current report
Officer or director change
|
Oct 12, 2021 | Oct 10, 2021 |
| 8-K |
Current report
Other events
|
Sep 13, 2021 | Sep 8, 2021 |
| 8-K |
Current report
Regulation FD disclosure
|
Aug 13, 2021 | Aug 11, 2021 |
| 10-Q | Quarterly report | Aug 6, 2021 | Jun 30, 2021 |
| 8-K |
Current report
Results of operations
|
Aug 6, 2021 | Aug 6, 2021 |
| 8-K |
Current report
Regulation FD disclosure
|
Jul 19, 2021 | Jul 13, 2021 |
| 8-K |
Current report
Other events
|
Jun 29, 2021 | Jun 29, 2021 |
| 11-K | Employee savings plan report | Jun 15, 2021 | Dec 31, 2020 |
| 8-K |
Current report
Regulation FD disclosure
|
Jun 4, 2021 | Jun 4, 2021 |
| 8-K |
Current report
Officer or director change, Shareholder vote results
|
May 28, 2021 | May 27, 2021 |
| 10-Q | Quarterly report | May 10, 2021 | Mar 31, 2021 |
| 8-K |
Current report
Results of operations
|
May 10, 2021 | May 10, 2021 |
| DEF 14A | Proxy statement | Apr 7, 2021 | May 27, 2021 |
| 10-K/A | Amended annual report | Mar 30, 2021 | Dec 31, 2020 |
| 8-K/A |
Amended current report
Acquisition or sale of assets
|
Mar 16, 2021 | Jan 1, 2021 |
| 10-K | Annual report | Feb 26, 2021 | Dec 31, 2020 |
| 8-K |
Current report
Results of operations
|
Feb 5, 2021 | Feb 5, 2021 |
| 8-K |
Current report
Acquisition or sale of assets
|
Jan 4, 2021 | Jan 1, 2021 |
| S-8 POS | Filing | Dec 30, 2020 | — |
| S-8 POS | Filing | Dec 30, 2020 | — |
| S-8 POS | Filing | Dec 30, 2020 | — |
| S-8 POS | Filing | Dec 30, 2020 | — |
| S-8 POS | Filing | Dec 30, 2020 | — |
| S-8 POS | Filing | Dec 30, 2020 | — |
| S-8 POS | Filing | Dec 30, 2020 | — |
| S-8 POS | Filing | Dec 29, 2020 | — |
| S-8 POS | Filing | Dec 29, 2020 | — |
| S-8 POS | Filing | Dec 29, 2020 | — |
| S-8 POS | Filing | Dec 29, 2020 | — |
| 8-K/A |
Amended current report
Officer or director change
|
Dec 21, 2020 | Dec 9, 2020 |
| 8-K |
Current report
Other events
|
Dec 21, 2020 | Dec 16, 2020 |
| 8-K |
Current report
Material agreement
|
Dec 15, 2020 | Dec 14, 2020 |
| 8-K |
Current report
Officer or director change
|
Dec 10, 2020 | Dec 9, 2020 |
| 8-K |
Current report
Officer or director change
|
Dec 1, 2020 | Nov 30, 2020 |
| 13F-NT | Filing | Nov 12, 2020 | Sep 30, 2020 |
| 8-K |
Current report
Results of operations
|
Nov 6, 2020 | Nov 6, 2020 |
| 10-Q | Quarterly report | Nov 6, 2020 | Sep 30, 2020 |
| 8-K |
Current report
Material agreement
|
Oct 1, 2020 | Oct 1, 2020 |
| 13F-NT | Filing | Aug 12, 2020 | Jun 30, 2020 |
| 10-Q | Quarterly report | Aug 7, 2020 | Jun 30, 2020 |
| 8-K |
Current report
Results of operations
|
Aug 7, 2020 | Aug 7, 2020 |
| UPLOAD | Letter from the SEC | Jun 17, 2020 | — |
| 11-K | Employee savings plan report | Jun 16, 2020 | Dec 31, 2019 |
| CORRESP | Letter to the SEC | Jun 10, 2020 | — |
| UPLOAD | Letter from the SEC | May 28, 2020 | — |
| 8-K |
Current report
Officer or director change, Shareholder vote results
|
May 22, 2020 | May 21, 2020 |
| 13F-NT | Filing | May 12, 2020 | Mar 31, 2020 |
| 8-K |
Current report
Results of operations
|
May 8, 2020 | May 8, 2020 |
| 10-Q | Quarterly report | May 8, 2020 | Mar 31, 2020 |
| 8-K |
Current report
Regulation FD disclosure
|
Apr 9, 2020 | Apr 7, 2020 |
| DEF 14A | Proxy statement | Apr 7, 2020 | May 21, 2020 |
| 10-K/A | Amended annual report | Mar 30, 2020 | Dec 31, 2019 |
| 8-K |
Current report
Other events
|
Mar 23, 2020 | Mar 20, 2020 |
| 10-K | Annual report | Mar 2, 2020 | Dec 31, 2019 |
| 13F-NT | Filing | Feb 12, 2020 | Dec 31, 2019 |
| 8-K |
Current report
Results of operations
|
Feb 5, 2020 | Feb 5, 2020 |
| 13F-NT | Filing | Nov 12, 2019 | Sep 30, 2019 |
| 10-Q | Quarterly report | Nov 6, 2019 | Sep 30, 2019 |
| 8-K |
Current report
Results of operations
|
Nov 6, 2019 | Nov 6, 2019 |
| 8-K |
Current report
Officer or director change
|
Aug 30, 2019 | Aug 29, 2019 |
| 13F-NT | Filing | Aug 8, 2019 | Jun 30, 2019 |
| 10-Q | Quarterly report | Aug 6, 2019 | Jun 30, 2019 |
| 8-K |
Current report
Results of operations
|
Aug 6, 2019 | Aug 6, 2019 |
| 8-K |
Current report
Other events
|
Jun 28, 2019 | Jun 28, 2019 |
| 8-K |
Current report
Regulation FD disclosure
|
Jun 7, 2019 | Jun 7, 2019 |
| 8-K |
Current report
Shareholder vote results
|
May 24, 2019 | May 24, 2019 |
| 13F-NT | Filing | May 13, 2019 | Mar 31, 2019 |
| 10-Q | Quarterly report | May 6, 2019 | Mar 31, 2019 |
| 8-K |
Current report
Results of operations
|
May 6, 2019 | May 6, 2019 |
| 11-K | Employee savings plan report | May 6, 2019 | Dec 31, 2018 |
| DEF 14A | Proxy statement | Apr 8, 2019 | May 23, 2019 |
| 8-K |
Current report
Other events
|
Apr 4, 2019 | Apr 4, 2019 |
| 8-K |
Current report
Officer or director change
|
Mar 1, 2019 | Feb 27, 2019 |
| 10-K | Annual report | Feb 27, 2019 | Dec 31, 2018 |
| 8-K |
Current report
Other events
|
Feb 26, 2019 | Feb 26, 2019 |
| 8-K |
Current report
Other events
|
Feb 14, 2019 | Feb 14, 2019 |
| 13F-NT | Filing | Feb 13, 2019 | Dec 31, 2018 |
| 8-K |
Current report
Results of operations
|
Feb 6, 2019 | Feb 6, 2019 |
| 8-K |
Current report
Other events
|
Feb 4, 2019 | Feb 4, 2019 |
| 8-K |
Current report
Officer or director change, Other events
|
Jan 7, 2019 | Jan 3, 2019 |
| 13F-NT | Filing | Nov 7, 2018 | Sep 30, 2018 |
| 10-Q | Quarterly report | Nov 5, 2018 | Sep 30, 2018 |
| 8-K |
Current report
Results of operations
|
Nov 5, 2018 | Nov 5, 2018 |
| 8-K |
Current report
Officer or director change
|
Aug 24, 2018 | Aug 23, 2018 |
| 13F-NT | Filing | Aug 8, 2018 | Jun 30, 2018 |
| 10-Q | Quarterly report | Aug 7, 2018 | Jun 30, 2018 |
| 8-K |
Current report
Results of operations
|
Aug 7, 2018 | Aug 7, 2018 |
| 11-K | Employee savings plan report | Jun 29, 2018 | Dec 31, 2017 |
| 8-K |
Current report
Regulation FD disclosure
|
Jun 8, 2018 | Jun 8, 2018 |
| 8-K |
Current report
Officer or director change, Shareholder vote results
|
May 29, 2018 | May 24, 2018 |
| 8-K |
Current report
Other events
|
May 11, 2018 | May 11, 2018 |
Showing 200 filings, the most recent 200. Main filings leave out insider and ownership forms such as Form 4; choose a type above to see them. Each form opens on SEC.gov. Older filings are on SEC EDGAR.
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Company profile
- Industry
- Fire, Marine & Casualty Insurance (SIC 6331)
- Listed as
- WTM (NYSE)
- Fiscal year ends
- December 31
- Incorporated in
- Bermuda
- Headquarters
- Hanover, NH
- SEC filer status
- Large accelerated filer
- SEC CIK
- 776867
- Former names
- WHITE MOUNTAINS INSURANCE GROUP INC (until Oct 20, 1999); FUND AMERICAN ENTERPRISES HOLDINGS INC (until Feb 10, 1999)
Other Fire, Marine & Casualty Insurance companies
Source: SEC EDGAR filings. This is company-reported data, not investment advice.