HMS Bahamas (K503) was a Colony-class frigate of the United Kingdom that served during World War II.

Transferred to the United Kingdom under Lend-Lease on 6 December 1943, the ship served in the Royal Navy as HMS Bahamas (K503) on patrol and escort duty.

The most notable event of her career took place while she was part of the escort of an Arctic convoy in the Barents Sea on 11 November 1944; the German submarine U-365 blew the entire bow off of the British destroyer HMS Cassandra with a G7es ("GNAT") torpedo at 71°57′00″N 032°04′00″E / 71.95000°N 32.06667°E / 71.95000; 32.06667, and Bahamas took Cassandra under tow stern-first toward the Kola Inlet in the Soviet Union.

A Soviet tug later took over the tow from Bahamas and successfully delivered Cassandra to the Kola Inlet.

She was transferred to the U.S. Maritime Commission for disposal and subsequently sold to the John J. Duane Company of Quincy, Massachusetts, for scrapping on 16 December 1947.