She was transferred to the Royal Canadian Navy in 1940, where she served as HMCS St. Francis (I93) in the Battle of the Atlantic escorting convoys.

Bancroft was recommissioned 18 December 1939 and served with the Atlantic Squadron on the east coast until decommissioned at Halifax, Nova Scotia.

She joined the 4th Escort Group and on 20 May she rescued all the survivors of the steamship Starcrose which had to be sunk after being torpedoed by a submarine.

From early 1944 she was employed on training duties at Digby, Nova Scotia, where on 1 April 1945 she was declared surplus.

On 14 July 1945, the destroyer was under tow of the tug Peter Norman, and bound for Baltimore to be broken up for scrap by the Boston Iron & Metal Co.. After passing through the Cape Cod Canal, the vessels encountered a thick fog, which enshrouded Buzzards Bay.