Retained on the active list through the 1940s, Serrano operated in the Trust Territories during 1947. In 1948, she returned to the eastern Pacific and, into the summer of 1949, operated in the Hawaiian Islands and off the west coast. She then moved north for operations in the Aleutians before returning to California in February 1950 for inactivation. On 31 May, Serrano was decommissioned and berthed with the Pacific Reserve Fleet at San Francisco.