Form 8-K - Current report:
SEC Accession No. 0001628280-26-059191
Filing Date
2026-08-27
Accepted
2026-08-27 08:11:33
Documents
13
Period of Report
2026-08-26
Items
Item 5.02: Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers: Compensatory Arrangements of Certain Officers
Item 9.01: Financial Statements and Exhibits

Document Format Files

Seq Description Document Type Size
1 8-K wtm-20260826.htm   iXBRL 8-K 25418
2 EX-99.1 wtmex991pressrelease2026st.htm EX-99.1 3893
6 image1a.jpg GRAPHIC 65797
  Complete submission text file 0001628280-26-059191.txt   238211

Data Files

Seq Description Document Type Size
3 XBRL TAXONOMY EXTENSION SCHEMA DOCUMENT wtm-20260826.xsd EX-101.SCH 1872
4 XBRL TAXONOMY EXTENSION LABEL LINKBASE DOCUMENT wtm-20260826_lab.xml EX-101.LAB 21629
5 XBRL TAXONOMY EXTENSION PRESENTATION LINKBASE DOCUMENT wtm-20260826_pre.xml EX-101.PRE 12590
17 EXTRACTED XBRL INSTANCE DOCUMENT wtm-20260826_htm.xml XML 3656
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: 8-K | Act: 34 | File No.: 001-08993 | Film No.: 261325182
SIC: 6331 Fire, Marine & Casualty Insurance
(CF Office: 02 Finance)