USS Montana (BB-51) was a South Dakota-class battleship, the second United States Navy ship to be named in honor of the 41st state. Her keel was laid down on 1 September 1920 by the Mare Island Navy Yard. Her construction was suspended on 8 February 1922 at 27.6 percent complete, and canceled 17 August 1923 in accordance with the provisions of the Washington Naval Treaty. She was struck from the Naval Vessel Register on 24 August 1923 and sold on 25 October 1923 to be scrapped.