Commissioned at Quebec City on November 21, 1943, she arrived at Halifax on December 18 requiring a month's repairs. She carried out working-up exercises in Bermuda early in February, returning on February 18 to complete the exercises in St. Margaret's Bay. Continuing mechanical problems necessitated further repairs, which continued at Halifax until early in August. Having lost most of her original crew during this period, she had to return to Bermuda to work up again. Early in September, 1944, Riviere du Loup returned to Halifax and joined EG W-3, WEF. In October she was assigned to EG C-3 and left St. John's on November 13 to pick up her first transatlantic convoy, HX.319. On arrival in the U.K., still dogged by troubles, she underwent a month's repairs at Belfast. Her career as a mid-ocean escort ended with her arrival at Halifax late in May, 1945, from convoy ON.304, and she was paid off on July 2 and placed in reserve at Sorel. In 1947 she was sold to the Dominican Navy and renamed Juan Bautista Maggiolo. She was broken up in 1972.