Commissioned at Quebec City on September 11, 1941, Summerside arrived at Halifax on September 25. She was assigned to local escort duty out of Halifax and later Sydney but left St. John's on December 11 as ocean escort to SC.59 for Iceland, returning with ON.50. It was to be her only trip there. She left St. John's on January 25, 1942, for convoy SC.66 to Londonderry, returning with ON.71 to join WLEF in March. In July she was transferred to Gulf Escort Force until, earmarked for duties in connection with Operation "Torch", she left Halifax on October 19 for the U.K. For the next four months she was employed on U.K.-Mediterranean convoys, returning to Canada in mid-March, 1943, for a major refit at Saint John from April 11 to September 25. Her fo'c's'le was extended in the process. After working up at Halifax she joined EG C-5 and in April, 1944, after seven transatlantic trips, was assigned at Londonderry to Western Approaches Command for invasion duties. She was employed in U.K. waters until returning to Canada for two months' refit at Liverpool, N.S., commencing in mid-October. After further repairs at Halifax were completed on January 18, 1945, she proceeded to Bermuda for three weeks' workups. In March she sailed for the U.K. to serve with EG 41 (RN) out of Plymouth until the war's end. She returned to Canada at the end of May, was paid off at Sorel on July 6 and broken up at Hamilton in 1946.
Focsle Extended, Saint John, NB, 25 Oct 43