After shakedown off Bermuda, "Gillette" sailed from Boston on 2 January 1944 for Balboa, C.Z., where for four months she conducted intensive exercises with submarines and escorted a convoy to Guantanamo Bay, Cuba, and returned. She sailed 9 May for Puerto Limon, Costa Rica, on a good-will tour and visited Barranquilla, Colombia, as well before returning to Boston 2 June.