Pipit was built as M/V Spartan in 1936 by Martinolich Shipyard, Tacoma, Washington; acquired by the U.S. Navy at San Diego, California, on 18 October 1940, by purchase from Mr. Anton Sumic; conversion by Wilmington Boat Works, San Pedro, California, and completed on 22 March 1941; and placed in service on 28 March 1941.