The Tacoma class was a class of 96 patrol frigates which served in the United States Navy during World War II and the Korean War. Originally classified as gunboats (PG), they were reclassified as patrol frigates (PF) on 15 April 1943. The class is named for its lead ship, Tacoma, a Maritime Commission (MARCOM) S2-S2-AQ1 design, which in turn was named for the city of Tacoma, Washington. Twenty-one ships were transferred to the British Royal Navy, in which they were known as Colony-class frigates, and twenty-eight ships were transferred under Lend-Lease to the Soviet Navy, where they were designated as storozhevoi korabl, during World War II. All Tacoma-class ships in US service during World War II were manned by United States Coast Guard crews. Tacoma-class ships were transferred to the United States Coast Guard and various navies post-World War II.

The River class was a class of 151 frigates launched between 1941 and 1944 for use as anti-submarine convoy escorts in the North Atlantic. The majority served with the Royal Navy and Royal Canadian Navy (RCN), with some serving in the other Allied navies: the Royal Australian Navy (RAN), the Free French Naval Forces, the Royal Netherlands Navy and, post-war, the South African Navy.