
Portsmouth
- County:
- Rockingham County
- County Seat:
- No
- Area (mi²):
- 15.661
- State:
- New Hampshire
Portsmouth is a city located in Rockingham County, New Hampshire. Portsmouth has a 2025 population of 23,227. Portsmouth is currently growing at a rate of 1.07% annually and its population has increased by 5.62% since the most recent census, which recorded a population of 21,992 in 2020.
The average household income in Portsmouth is $143,256 with a poverty rate of 5.5%. The median age in Portsmouth is 42.4 years: 41.4 years for males, and 44.4 years for females.