There have been no material changes to any of the risk factors previously disclosed in the Registrant’s 2025 Annual Report on Form 10-K. Item 2.Issuer Purchases of Equity Securities. Months Total Number of Shares Purchased Average Price Paid per Share Total Number of Shares Purchased as Part of Publicly Announced Plans (1) Maximum Number of Shares that May Yet Be Purchased Under the Plans April 1 - April 30, 2026 — $ — — 261,201 May 1 - May 31, 2026 56,378 $ 2,119.96 56,378 204,823 June 1 - June 30, 2026 34,816 $ 2,048.62 34,816 170,007 Total 91,194 $ 2,092.72 91,194 170,007 (1) White Mountains’s Board of Directors has authorized the Company to repurchase its common shares, from time to time, subject to market conditions. The repurchase authorizations do not have a stated expiration date. Item 3. Defaults Upon Senior Securities. None. Item 4.Mine Safety Disclosures. None.