12 cities
| City | County | 2026 Pop. ↓ |
|---|---|---|
| Dover | Strafford County | 34,721 |
| Derry | Rockingham County | 34,156 |
| Durham | Strafford County | 15,228 |
| Deerfield | Rockingham County | 5,035 |
| Danville | Rockingham County | 4,723 |
| Dunbarton | Merrimack County | 3,316 |
| Deering | Hillsborough County | 1,932 |
| Dublin | Cheshire County | 1,625 |
| Danbury | Merrimack County | 1,317 |
| Dalton | Coos County | 898 |
| Dorchester | Grafton County | 335 |
| Dummer | Coos County | 315 |