UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934

May 24, 2012

Date of Report (Date of earliest event reported)

WHITE MOUNTAINS INSURANCE GROUP, LTD.

(Exact name of registrant as specified in its charter)

80 South Main Street, Hanover, New Hampshire 03755

(Address of principal executive offices)

(603) 640-2200

(Registrant’s telephone number, including area code)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

o Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

o    Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

o    Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

o    Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

ITEM 5.07  Submission of Matters to a Vote of Security Holders.

White Mountains Insurance Group, Ltd. (the “Company”) held its 2012 Annual General Meeting of Members (the “2012 Annual Meeting”) on May 24, 2012 in Bermuda.

As of March 30, 2012, the record date for the 2012 Annual Meeting, a total of 6,638,873 common shares were eligible to vote; however, in accordance with the Company’s Bye-laws, direct and constructive holders of common shares (other than John J. Byrne and his affiliates except in connection with director voting) whose votes would otherwise confer 10% or more of the votes conferred by all the issued shares of the Company are subject to a cut-back that reduces their total voting power to under 10%.  The results of the vote, after applying the voting cut-backs which are required by the Company’s Bye-laws, are presented below.

Proposal 1 - Election of the Class III Directors to a term ending in 2015.

Proposal 2 - Election of Directors of Sirius International Insurance Corporation.

Proposal 3 - Election of Directors of Scandinavian Reinsurance Company Ltd.

Proposal 4 - Election of Directors of White Mountains Life Reinsurance (Bermuda) Ltd.

Proposal 5 - Election of Directors of White Shoals Re Ltd.

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Proposal 6 - Election of Directors of Star Re Ltd.

Proposal 7 - Election of Directors of White Mountains Re Sirius Capital Ltd.

Proposal 8 - Election of Directors for Any New Designated Subsidiary.

Proposal 9 - Approval of the advisory resolution on executive compensation.

Proposal 10 - Approval of the appointment of PricewaterhouseCoopers LLP as the Company’s Independent Registered Accounting Firm for 2012.

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SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned thereunto duly authorized.

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