Mainwaring was a schooner launched in Ipswich in 1807. The Hudson's Bay Company (HBC) acquired her and she spent the rest of her career sailing for the HBC until she was broken up in 1820. Mainwaring first appeared in the registers in the Register of Shipping (RS) in 1809 with Davidson, master, Hudson's Bay Company, owner, and trade London–Hudson Bay. By then Captain John Davidson had sailed her to York Factory. From 1808 until she was broken up she operated out of Moose Factory; her main function was to supply Fort Sever, though she visited other posts around the bay as well. In 1815, though, she was decommissioned and in 1820 she was found unseaworthy and was broken up.