via email: Barbara.McWhirter@lom.com
Jennifer MoyerChief Administrative Officer
March 4, 2026
Barbara McWhirter Corporate Finance LOM Capital Limited The LOM Building 27 Reid Street
Hamilton HM 11 Bermuda
Dear Barbara:
Please accept this letter as notice of this year's Annual Meeting arrangements: Company: White Mountains Insurance Group, Ltd.
Meeting date: Thursday, May 21, 2026
Record date: Monday, March 30, 2026
Cusip number: G9618E107
Location: Hamilton Parish, Bermuda
Please feel free to contact me at (603) 640-2210 if you have any questions or if I can provide any additional information relating to the meeting.
Sincerely,
Jennifer Moyer
cc: Bermuda Stock Exchange: listings@bsx.com
WTM - John Sinkus jsinkus@whitemountains.com
Corporate Headquarters:
White Mountains Insurance Group, Ltd.
A.S. Cooper Building, 26 Reid Street Hamilton HM 11, Bermuda
Ph: 441-278-3160 ✯ Fax: 441-278-3170
Hanover Office:
White Mountains Insurance Group, Ltd.
23 South Main Street, Suite 3B, Hanover, NH 03755 Ph: 603-640-2210 ✯ Fax: 603-640-2250
E-mail: jmoyer@whitemountains.com