Her keel was laid down by the Union Iron Works in San Francisco, California, under subcontract from Electric Boat Company of Groton, Connecticut.

She was launched on 11 July 1914 sponsored by Mrs. John W. Lewis, wife of the first commanding officer, and commissioned on 1 December at Mare Island.

For more than two years she operated with K-3, K-4, and K-7, developing and perfecting submarine techniques in diving, torpedo firing, and underwater tactics.

Departing Galveston 21 November, she returned to Key West to continue experimental operations along the Florida coast until she sailed for Philadelphia, Pennsylvania, on 14 April 1919.

After returning to Philadelphia 8 June 1920, she proceeded to Annapolis, Maryland, on 19 January 1921, for training operations at the United States Naval Academy.