Commissioned on May 26, 1942, at Montreal, she arrived at Halifax on June 10 and was allocated to WLEF at the end of July. In September she was appointed to Operation "Torch" duties, arriving at Londonderry on November 1 from convoy SC.105, and during the next four months escorted U.K.-Mediterranean convoys. On January 19, 1943, while so employed, Port Arthur sank the Italian submarine Tritone off Bougie, Algeria. She arrived at Halifax on March 23, 1943, and, after brief repairs there, joined Western Support Force at St. John's. Early in August she began a major refit at Liverpool, N.S., completing on December 31. After working up at Halifax, she joined EG W-9, WEF. In April, 1944, she was assigned to Western Approaches Command for invasion duties and left St. John's on April 24 for Londonderry. During the following four months she was occupied as a convoy escort in support of the invasion, and in September joined Portsmouth Command. In February, 1945, she returned to Canada, where VE-Day found her still under refit at Liverpool, N.S. She was paid off July 11 at Sorel and broken up at Hamilton in 1948.