Portsmouth
- Country: United States
- State: New Hampshire
- Population: 21,485 (2016)
- Latitude: 43° 4.3' N (43.07176°)
- Longitude: 70° 45.8' W (-70.76255°)
- Elevation: 6 m/19 ft. above sea level
- Time zone: America/New_York (UTC -05:00); DST observed (UTC -04:00)
- Alternate names: Pascataquack, Piscataqua, Rivertown, Strabery Banke, Strawberry Banck, Strawberry Bancke, Strawberry Bank, Strawberry-bank, Strawbery Banke, The Bank