13F Filings History of WHITE MOUNTAINS INSURANCE GROUP LTD

13F snapshot Latest parsed holdings, value, and filing-period context. 1 signal
Form 13F summary
  • WHITE MOUNTAINS INSURANCE GROUP LTD Form 13F history summarizes parsed U.S.-listed equity disclosures for this manager.
  • Form 13F is generally due within 45 days after each calendar quarter ends.
  • WHITE MOUNTAINS INSURANCE GROUP LTD reported 2 equity holdings with a total reported market value of $313,368,520 for Q1 2026.
Manager Names, identifiers, and filing context for this profile. 2 identity fields
Manager signature
Michaela J. Hildreth - Managing Director and Chief Accounting Officer
Manager location
Hanover, NH

Follow Filing Activity

Follow WHITE MOUNTAINS INSURANCE GROUP LTD with Pro and return when a new 13F portfolio filing changes the record on this page.

Pro alert delivery is coming soon and remains tied to source-backed filing changes rather than inferred market advice.

Holdings Value

Form 13F evidence

Quarterly portfolio filings

SEC-reported 13F quarters for this filer, ordered by the latest accepted filing.

Latest quarter
Q1 2026
Latest value
$313,368,520
Quarter delta
+$51,438,969
Accepted
12 May 2026, 16:01
Rows shown
1-25 of 50
Quarter Holdings SEC-reported value Bought Sold Net Top Holdings Form Type Accepted by SEC
Q1 2026 2 $313,368,520 +$118,036,710 $0 +$118,036,710 MAX, SPY 13F-HR 12 May 2026, 16:01
Q4 2025 2 $261,929,551 +$30,686,400 $0 +$30,686,400 MAX, SPY 13F-HR 12 Feb 2026, 17:26
Q3 2025 1 $203,208,267 $0 $0 $0 MAX 13F-HR 13 Nov 2025, 08:28
Q2 2025 1 $195,529,923 $0 -$120,938,440 -$120,938,440 MAX 13F-HR 11 Aug 2025, 16:19
Q1 2025 2 $285,933,553 $0 -$93,389,601 -$93,389,601 MAX, SPY 13F-HR 12 May 2025, 16:13
Q4 2024 2 $426,155,380 $0 $0 $0 SPY, MAX 13F-HR 12 Feb 2025, 16:23
Q3 2024 2 $543,217,129 $0 $0 $0 MAX, SPY 13F-HR 12 Nov 2024, 16:18
Q2 2024 2 $443,687,322 +$50,775,726 -$65,852,634 -$15,076,908 MAX, SPY 13F-HR 08 Aug 2024, 16:05
Q1 2024 2 $617,203,048 $0 $0 $0 MAX, SPY 13F-HR 09 May 2024, 16:39
Q4 2023 2 $392,620,178 $0 -$142,593,000 -$142,593,000 MAX, SPY 13F-HR 13 Feb 2024, 16:22
Q3 2023 2 $440,944,652 $0 -$10,687,000 -$10,687,000 SPY, MAX 13F-HR 09 Nov 2023, 07:15
Q2 2023 2 $508,202,687 +$61,002,373 -$114,410,568 -$53,408,195 SPY, MAX 13F-HR 10 Aug 2023, 08:18
Q1 2023 2 $611,136,533 $0 $0 $0 SPY, MAX 13F-HR 11 May 2023, 07:35
Q4 2022 2 $502,393,719 +$284,124,839 $0 +$284,124,839 SPY, MAX 13F-HR 13 Feb 2023, 16:12
Q3 2022 2 $194,658,000 +$46,433,000 $0 +$46,433,000 MAX, SPY 13F-HR 09 Nov 2022, 16:10
Q2 2022 1 $166,859,000 $0 $0 $0 MAX 13F-HR 12 Aug 2022, 08:33
Q1 2022 1 $280,357,000 $0 $0 $0 MAX 13F-HR 12 May 2022, 16:05
Q4 2021 1 $261,554,000 $0 $0 $0 MAX 13F-HR 11 Feb 2022, 16:06
Q3 2021 1 $316,439,000 $0 $0 $0 MAX 13F-HR 12 Nov 2021, 08:19
Q2 2021 1 $713,174,000 $0 $0 $0 MAX 13F-HR 12 Aug 2021, 16:09
Q1 2021 1 $600,184,000 $0 -$127,271,760 -$127,271,760 MAX 13F-HR 14 May 2021, 08:45
Q4 2020 1 $802,193,000 $0 $0 $0 MAX 13F-HR 12 Feb 2021, 16:12
Q3 2020 0 $0 13F-NT 12 Nov 2020, 15:42
Q2 2020 0 $0 13F-NT 12 Aug 2020, 16:03
Q1 2020 0 $0 13F-NT 12 May 2020, 16:06
We use cookies and similar technologies to provide certain features, enhance the user experience and, if you allow them, measure engagement and deliver advertising. Analytics and marketing storage stay off until you grant consent. By clicking on "Agree and continue", you declare your consent to the use of the selected optional cookies. Manage preferences to update or revoke optional consent for future visits. For more information, see our Privacy Policy .