12 cities
| City | County | 2025 Pop. ↓ |
|---|---|---|
| Dover | Strafford County | 34,315 |
| Derry | Rockingham County | 34,109 |
| Durham | Strafford County | 15,249 |
| Deerfield | Rockingham County | 5,009 |
| Danville | Rockingham County | 4,674 |
| Dunbarton | Merrimack County | 3,251 |
| Deering | Hillsborough County | 1,927 |
| Dublin | Cheshire County | 1,609 |
| Danbury | Merrimack County | 1,310 |
| Dalton | Coos County | 905 |
| Dorchester | Grafton County | 337 |
| Dummer | Coos County | 314 |