Commissioned on July 31, 1943, at Esquimalt, St. Catharines arrived at Halifax on October 4 and in November sailed for the U.K. as a member of EG C-2. She was continuously employed on convoy duty until October 1944, and from February to September of that year was Senior Officer's ship. With six other escorts of convoy HX.280, she took part in the destruction of U 744 on March 6, 1944. After refitting at Shelburne from October to December 1944, she went to Bermuda to work up and, on her return to Halifax commenced tropicalization refit there. By the time this was completed in August, 1945, the war was over and the ship was paid off on November 18. In 1947 she was sold to Marine Industries Ltd. and laid up at Sorel, but was reacquired in 1950 and converted to a weather ship. Now owned by the Department of Transport, she was taken round to the west coast to be stationed in the North Pacific as of July, 1952. Replaced in March, 1967, by CGS Vancouver, she was broken up in Japan in 1968.