The ship was ordered from Harland and Wolff at Belfast on 2 February 1943 as a Loch-class frigate to be named Loch Frisa and laid down on 26 April 1944 as Admiralty Job Number J3917.

During construction the contract was changed, and the ship was completed as a Bay-class frigate and named Widemouth Bay on 5 October 1944.

She arrived at the Forward Base of the British Pacific Fleet at Manus, Admiralty Islands, in August, just after the Japanese surrender.

She remained on the Far East Station, based at Hong Kong, for the next year and a half, supporting post-war repatriation operations, carrying out patrols and escort duties.

[1] Widemouth Bay was placed on the Disposal List in 1957, and sold to the British Iron & Steel Corporation (BISCO) for breaking up by Hughes Bolckow.