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

Date of Report (Date of earliest event reported): March 31, 2014

RenaissanceRe Holdings Ltd.

(Exact name of registrant as specified in its charter)

Registrant’s telephone number, including area code: (441) 295-4513

Not Applicable

(Former name or former address, if changed since last report)

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:

RenaissanceRe Holdings Ltd. (“RenaissanceRe”) and its affiliates, Renaissance Reinsurance Ltd., Renaissance Reinsurance of Europe, RenaissanceRe Specialty Risks Ltd. (formerly Glencoe Insurance Ltd.) and DaVinci Reinsurance Ltd. (such affiliates, collectively, the “Account Parties”), entered into a Fourth Amended and Restated Reimbursement Agreement, dated as of May 17, 2012 (as amended, the “Reimbursement Agreement”), with various banks and financial institutions parties thereto (collectively, the “Banks”), Wells Fargo Bank, National Association, as issuing bank, collateral agent and administrative agent for the Banks, and certain other agents. After giving effect to a reduction in commitments in March 2013, the Reimbursement Agreement previously provided for commitments from the Banks in an aggregate amount of $250 million. The commitments under the Reimbursement Agreement expire on May 17, 2015.

Effective as of March 31, 2014, RenaissanceRe further reduced the commitments under the Reimbursement Agreement from $250 million to $180 million. The reduction was implemented in connection with a reassessment by RenaissanceRe of the future collateral needs of the Account Parties, taking into account, among other things, its and their access to alternative sources of credit enhancement. Prior to the expiration date set forth above and after giving effect to the $70 million reduction, the commitments of the Banks under the Reimbursement Agreement may, from time to time and subject to the satisfaction of certain conditions, be increased by up to $350 million, such that the total commitments may be increased up to an aggregate amount not to exceed $530 million.

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SIGNATURES

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

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