10 cities
| City | County | 2025 Pop. ↓ |
|---|---|---|
| Portsmouth | Rockingham County | 23,113 |
| Pelham | Hillsborough County | 14,852 |
| Plaistow | Rockingham County | 7,911 |
| Pembroke | Merrimack County | 7,617 |
| Plymouth | Grafton County | 6,634 |
| Peterborough | Hillsborough County | 6,452 |
| Pittsfield | Merrimack County | 4,153 |
| Plainfield | Sullivan County | 2,556 |
| Pittsburg | Coos County | 842 |
| Piermont | Grafton County | 767 |