USS Doran was decommissioned at Halifax, Nova Scotia on 22 September 1940 and transferred in the destroyer-land bases exchange to Great Britain. She was renamed HMS St.Marys and arrived at Belfast, Ireland, 8 October 1940.

She was assigned to the permanent escort force of the 1st Minelaying Squadron, she arrived on the west coast of Scotland 31 October and took part in some of the early minelaying operations in Denmark Strait, between Iceland and Greenland.

She also escorted a number of convoys. During 1941 she took part in most of the Squadron's minelaying operations and rendered valuable service in the defense of shipping. On 29 August 1941 she was in a collision with the transport Royal Ulsterman off the west coast of Scotland and was in the dockyard until December.

St. Marys carried out minelaying and shipping defense duties in 1942 and 1943, later she was used as aircraft target. In February 1944 she was paid off on the Tyne and placed in reserve fleet. She was sold for scrap on 20 Mar, 1945 at Rosyth.

Commanding Officers:
Lt.Cdr. Karl Henry John Lynch Phipps, RN
October 1940 – ca. December 1942

HMS St. Marys in Dockyard Control during repairs

Lt. David Brian Gladstone Dumas, RN
February 1943 – still in command in August 1943 according to the Navy List

HMS St. Marys is not listed as active unit in the April 1944 Navy List