In accordance with a United States Department of the Navy general order that all section patrol craft should have their names shortened to surnames or single words (as applicable), City of Lewes was renamed USS Lewes (SP-383) in July 1917. However, she still often was called USS City of Lewes for the remainder of her Navy career.
After fitting out as a minesweeper, Lewes departed Philadelphia, Pennsylvania, on 14 August 1917 bound for Brest, France, which she reached on 18 September 1917. Following voyage repairs, she took up patrol and convoy escort duties, which she pursued for the remainder of World War I. She also engaged in minesweeping to keep shipping channels free of German naval mines, and she continued minesweeping work after the end of the war and into 1919.
Lewes was decommissioned at Brest on 8 September 1919 and sold abroad.