Four vessels of the United States Navy have been named USS Portsmouth, after the seaport city of Portsmouth, New Hampshire.

• The first Portsmouth was a 24-gun ship in service from 1798 to 1801.

• The second Portsmouth was a sloop-of-war commissioned in 1844, active in the American Civil War, decommissioned in 1878 but continuing as a training ship until 1915.

• The third Portsmouth (CL-102) was a light cruiser in service from 1945 to 1949.

• The fourth Portsmouth (SSN-707) was a Los Angeles-class nuclear attack submarine commissioned in 1983 and decommissioned in 2004.