Page 1

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington , D.C. 20549 Form 20 - F ☐ REGISTRATION STATEMENT PURSUANT TO SECTION 12 ( b ) OR 12 ( g ) OF THE SECURITIES EXCHANGE ACT OF 1934 ☑ OR ANNUAL REPORT PURSUANT TO SECTION 13 OR 15 ( d ) OF THE SECURITIES EXCHANGE ACT OF 1934 For the fiscal year ended December 31 , 2020 OR ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15 ( d ) OF THE SECURITIES EXCHANGE ACT OF 1934 OR ☐ SHELL COMPANY REPORT PURSUANT TO SECTION 13 OR 15 ( d ) OF THE SECURITIES EXCHANGE ACT OF 1934 Commission file number 001-31909 A ASPEN INSURANCE HOLDINGS LIMITED ( Exact name of registrant as specified in its charter ) Bermuda ( Jurisdiction of incorporation or organization ) 141 Front Street , Hamilton , HM19 , Bermuda ( Address of principal executive offices ) Mark Cloutier Executive Chairman and Chief Executive Officer 141 Front Street , Hamilton , HM19 , Bermuda Telephone : +1 441-295-8201 , Email : mark.cloutier@aspen.co ( Name , Telephone , E - mail and / or Facsimile Number and Address of Company Contact Person ) Title of Each Class Name of Each Exchange on Which Registered Securities registered pursuant to Section 12 ( b ) of the Act : 5.95 % Fixed - to - Floating Rate Perpetual Non - Cumulative Preference Shares 5.625 % Perpetual Non - Cumulative Preference Shares Depositary Shares , each representing a 1 / 1000th interest in a share of 5.625 % Perpetual Non - Cumulative Preference Shares Trading Symbol AHL PRC AHL PRD New York Stock Exchange New York Stock Exchange AHL PRE New York Stock Exchange Securities registered pursuant to Section 12 ( g ) of the Act : None . Securities for which there is a reporting obligation pursuant to Section 15 ( d ) of the Act : None . Indicate the number of outstanding shares of each of the issuer's classes of capital or common stock as of the close of the period covered by the annual report : 60,395,839 ordinary shares . Indicate by check mark if the registrant is a well - known seasoned issuer , as defined in Rule 405 of the Securities Act . Yes No ☑ If this report is an annual or transition report , indicate by check mark if the registrant is not required to file reports pursuant to Section 13 or Section 15 ( d ) of the Act : Yes No ☑ Indicate by check mark whether the registrant ( 1 ) has filed all reports required to be filed by Section 13 or 15 ( d ) of the Exchange Act of 1934 during the preceding 12 months ( or for such shorter periods that the registrant was required to file such reports ) , and ( 2 ) has been subject to such filing requirements for the past 90 days . Yes ý No □ Indicate by check mark whether the registrant has submitted electronically every Interactive Data File required to be submitted pursuant to Rule 405 of Regulation S - T ( $ 232.405 of this chapter ) during the preceding 12 months ( or for such shorter period that the registrant was required to submit such files ) . Yes No □ Indicate by check mark whether the registrant is a large accelerated filer , an accelerated filer , a non - accelerated filer , a smaller reporting company or an emerging growth company . See the definitions of " large accelerated filer , " " accelerated filer , " " smaller reporting company " and " emerging growth company " in Rule 12b - 2 of the Exchange Act .: ☐ Accelerated filer ☐ Large accelerated filer Non - accelerated filer 冈 Smaller reporting company ☐ Emerging growth company If an emerging growth company that prepares its financial statements in accordance with U.S. GAAP , indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13 ( a ) of the Exchange Act . □ Indicate by check mark which basis of accounting the registrant has used to prepare the financial statements included in this filing : ㅁ International Financial Reporting Standards as issued by the International Accounting Standards U.S. GAAP ☑ Board ㅁ Other ☐ If this is an annual report , indicate by check mark whether the registrant is a shell company ( as defined in Rule 12b - 2 of the Act ) . Yes ☐ No ☑