40 or USS S.C. 40, was an SC-1-class submarine chaser built for the United States Navy during World War I. SC-40 was a wooden-hulled 110-foot (34 m) submarine chaser built at the New York Navy Yard at Brooklyn, New York.

40 participated in North Sea minesweeping operations to clear the North Sea Mine Barrage after World War I.

When the U.S. Navy adopted its modern hull number system on 17 July 1920, Submarine Chaser No.

On 14 October 1924, the Navy sold SC-40 to the Florida Boat Company of Washington, D.C.

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