Page 1

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington , D.C. 20549 ( Mark One ) ANNUAL REPORT PURSUANT TO SECTION 13 OR 15 ( D ) OF THE SECURITIES EXCHANGE ACT OF 1934 For the fiscal year ended December 31 , 2020 TRANSITION REPORT PURSUANT TO SECTION 13 OR 15 ( D ) OF THE SECURITIES EXCHANGE ACT OF 1934 FORM 10 - K FOR THE TRANSITION PERIOD FROM Delaware ( State or other jurisdiction of incorporation or organization ) OR Commission File Number 001-38971 145 Newton Street Boston , Massachusetts ( Address of principal executive offices ) XL Fleet Corp. ( Exact name of Registrant as specified in its Charter ) Title of Each Class : Shares of common stock , $ 0.0001 par value Securities registered pursuant to Section 12 ( b ) of the Act : ΤΟ 02135 ( Zip Code ) Registrant's telephone number , including area code : ( 617 ) 718-0329 Trading Symbol ( s ) XL 83-4109918 ( I.R.S. Employer Identification Number ) Name of Each Exchange on Which Registered : New York Stock Exchange Securities registered pursuant to Section 12 ( g ) of the Act : None Indicate by check mark if the Registrant is a well - known seasoned issuer , as defined in Rule 405 of the Securities Act . Yes No Indicate by check mark if the Registrant is not required to file reports pursuant to Section 13 or Section 15 ( d ) of the Exchange Act . Yes No X Indicate by check mark whether the Registrant ( 1 ) has filed all reports required to be filed by Section 13 or 15 ( d ) of the Securities Exchange Act of 1934 during the preceding 12 months ( or for such shorter period that the Registrant was required to file such reports ) , and ( 2 ) has been subject to such filing requirements for the past 90 days . Yes 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 and post 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 definition of " large accelerated filer , " " accelerated filer , “ smaller reporting company " and " emerging growth company " in Rule 12b - 2 of the Exchange Act .