Form 10-Q - Quarterly report [Sections 13 or 15(d)]:
SEC Accession No. 0001628280-25-049910
Filing Date
2025-11-06
Accepted
2025-11-06 09:07:05
Documents
489
Period of Report
2025-09-30

Document Format Files

Seq Description Document Type Size
1 10-Q wtm-20250930.htm   iXBRL 10-Q 4754974
2 EX-10.1 exhibit101.htm EX-10.1 3920
3 EX-10.2 exhibit102.htm EX-10.2 1329192
4 EX-10.3 exhibit103.htm EX-10.3 34557
5 EX-31.1 wtmq32025ex311.htm EX-31.1 8974
6 EX-31.2 wtmq32025ex312.htm EX-31.2 9068
7 EX-32.1 wtmq32025ex321.htm EX-32.1 6215
8 EX-32.2 wtmq32025ex322.htm EX-32.2 6156
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  Complete submission text file 0001628280-25-049910.txt   154738713

Data Files

Seq Description Document Type Size
9 XBRL TAXONOMY EXTENSION SCHEMA DOCUMENT wtm-20250930.xsd EX-101.SCH 134096
10 XBRL TAXONOMY EXTENSION CALCULATION LINKBASE DOCUMENT wtm-20250930_cal.xml EX-101.CAL 137782
11 XBRL TAXONOMY EXTENSION DEFINITION LINKBASE DOCUMENT wtm-20250930_def.xml EX-101.DEF 882102
12 XBRL TAXONOMY EXTENSION LABEL LINKBASE DOCUMENT wtm-20250930_lab.xml EX-101.LAB 1256127
13 XBRL TAXONOMY EXTENSION PRESENTATION LINKBASE DOCUMENT wtm-20250930_pre.xml EX-101.PRE 1069152
492 EXTRACTED XBRL INSTANCE DOCUMENT wtm-20250930_htm.xml XML 4868523
Mailing Address 23 SOUTH MAIN STREET SUITE 3B HANOVER NH 03755
Business Address 23 SOUTH MAIN STREET SUITE 3B HANOVER NH 03755 603 640 2200
WHITE MOUNTAINS INSURANCE GROUP LTD (Filer) CIK: 0000776867 (see all company filings)

EIN.: 942708455 | State of Incorp.: D0 | Fiscal Year End: 1231
Type: 10-Q | Act: 34 | File No.: 001-08993 | Film No.: 251456488
SIC: 6331 Fire, Marine & Casualty Insurance
(CF Office: 02 Finance)