The ship, originally designated a "patrol gunboat," PG-197, was ordered by the United States Maritime Commission under a United States Navy contract as USS Phillimore. She was reclassified as a "patrol frigate," PF-89, on 15 April 1943 and laid down by the Walsh-Kaiser Company at Providence, Rhode Island, on 7 October 1943. Intended for transfer to the United Kingdom, the ship was first renamed Sierra Leone and then Perim by the British prior to launching and was launched on 5 November 1943.
Transferred to the United Kingdom under Lend-Lease on 16 March 1944, the ship served in the Royal Navy as HMS Perim (K593). Her first commanding officer was Nicholas Monsarrat. Conducting work-ups off Bermuda, she damaged her main bearings during each of her first 13 sea trials before the problem was identified and corrected and she completed trials successfully on her fourteenth try. She then served on patrol and escort duty until decommissioned in 1945.
The United Kingdom returned Perim to the U.S. Navy on 22 May 1946. She was scrapped in 1947.