The United States N class submarines were a class of seven coastal defense submarines of the United States Navy. The boats were constructed by two companies to slightly different specifications; N-1, N-2, and N-3 by the Seattle Construction and Drydock Company of Seattle, Washington, and N-4, N-5, N-6, and N-7 by the Lake Torpedo Boat Company of Bridgeport, Connecticut. The N-boats built by Lake are sometimes considered a separate class. Commissioned during World War I, they were assigned to the 1st Naval District and patrolled the New England coast.