6-K

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549

FORM 6-K

REPORT OF FOREIGN PRIVATE ISSUER PURSUANT TO RULE 13a-16 OR 15d-16 UNDER
THE SECURITIES EXCHANGE ACT OF 1934

June 10, 2025

Commission File Number: 001-41731

FIDELIS INSURANCE HOLDINGS LIMITED (Exact Name of Registrant as Specified in its Charter)

Wellesley House South, 90 Pitts Bay Road, Pembroke, Bermuda, HM08 +1 441 279 2590 (Address of Principal Executive Office)

Indicate by check mark whether the registrant files or will file annual reports under cover of Form 20-F or Form 40-F.

Form 20-F ☒    Form 40-F ☐

Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101(b)(1):

Yes ☐    No ☒

Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101(b)(7):

Yes ☐    No ☒

On June 10, 2025, Fidelis Insurance Holdings Limited (the “Company”) priced the issue of its US$400,000,000 Fixed-Rate Reset Subordinated Notes due 2055 (the “Notes”) pursuant to the Company’s automatic shelf registration statement on Form F-3 (File No. 333-287332) filed with the U.S. Securities and Exchange Commission as supplemented by the preliminary prospectus supplement filed on June 9, 2025. The issuance is expected to close on June 13, 2025, subject to the satisfaction of customary closing conditions. The press release, furnished as Exhibit 99.1 to this Form 6-K, is incorporated by reference as part of this Form 6-K.

The information included in this Form 6-K shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), or incorporated by reference in any filing under the Securities Act of 1933, as amended, or the Exchange Act, except as shall be expressly set forth by specific reference in such filing.

EXHIBIT INDEX

Exhibit

99.1        Press Release

Pursuant to the requirement 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.

Document

Fidelis Insurance Holdings Limited Announces Pricing of $400 Million of 7.750% Fixed-Rate Reset Subordinated Notes Due 2055

PEMBROKE, Bermuda, June 10, 2025 — Fidelis Insurance Holdings Limited (NYSE:FIHL) ("Fidelis Insurance Group" or the "Company"), a global specialty insurer, announced today the pricing of $400 million aggregate principal amount of its 7.750% Fixed-Rate Reset Subordinated Notes due 2055 (the “Notes”). The offering is expected to close on June 13, 2025, subject to satisfaction of customary closing conditions.

Fidelis Insurance Group intends to use a portion of the net proceeds from this offering to fund its redemption of the 9.00% Fixed Rate/Floating Rate Cumulative Preference Shares, Series A, par value U.S. $0.01. The Company intends to use the remaining net proceeds from this offering for general corporate purposes.

Wells Fargo Securities, Barclays and Lloyds Securities are acting as joint book-running managers for the offering.

The Notes are being offered pursuant to an effective shelf registration statement that has previously been filed with the U.S. Securities and Exchange Commission (the “SEC”). This press release does not constitute an offer to sell or a solicitation of an offer to buy nor shall there be any sale of securities in any state or jurisdiction in which such offer, solicitation or sale would be unlawful prior to registration or qualification under the securities laws of any such state or jurisdiction. Any offer to sell or solicitation to buy will be made solely by means of a prospectus and related prospectus supplement filed with the SEC. You may obtain these documents without charge from the SEC at www.sec.gov. Alternatively, you may request copies of these materials from the joint book-running managers by contacting Wells Fargo Securities, LLC toll-free at 1-800-645-3751, Barclays Capital Inc. toll-free at 1-888-603-5847, or Lloyds Securities Inc. at 1-212-930-5039.

About Fidelis Insurance Group

Fidelis Insurance Group is a global specialty insurer, leveraging strategic partnerships to offer innovative and tailored insurance solutions.

We have a highly diversified portfolio that we believe allows us to take advantage of the opportunities presented by evolving (re)insurance markets, proactively shift our business mix across market cycles, and produce superior underwriting returns.

Headquartered in Bermuda, with offices in Ireland and the United Kingdom, Fidelis Insurance Group operating companies have an insurer financial strength rating of A from AM Best, A- from S&P and A3 from Moody’s.

CAUTIONARY STATEMENT CONCERNING FORWARD-LOOKING STATEMENTS

Certain statements contained in this press release, in interviews and in related posts, constitute “forward-looking statements,” and are made pursuant to the safe harbor provisions of the U.S. Private Securities Litigation Reform Act of 1995. These statements reflect management’s current beliefs, expectations, assumptions, estimates and projections. While the management believes these expectations, assumptions, estimates and projections are reasonable, such forward-looking statements are only predictions and are subject to known and unknown risks and uncertainties, many of which are beyond management’s control. These statements involve risks and uncertainties that may cause the Company’s actual results, performance or achievements to differ materially from any future results,

performance or achievements expressed or implied by these forward-looking statements. Important risk factors regarding the Company can be found under the heading “Risk Factors” in the Company’s Annual Report on Form 20-F for the year ended December 31, 2024, which are incorporated herein by reference. Forward-looking statements speak only as of the date they are made. Readers are cautioned not to rely on forward-looking statements, and, except as required by law, the Company assumes no obligation and does not intend to update or revise these forward-looking statements after the date of this press release, whether as a result of new information, future events, or otherwise.

Fidelis Insurance Group Investor Contact:

Fidelis Insurance Group

Miranda Hunter

+1 (441) 279 2561

miranda.hunter@fidelisinsurance.com

Fidelis Insurance Group Media Contacts:

Rein4ce

Sarah Hills

+44 (0)7718 882011

sarah.hills@rein4ce.co.uk