| City | County | 2026 Pop. ↓ |
|---|---|---|
| Londonderry | Rockingham County | 28,610 |
| Laconia | Belknap County | 17,226 |
| Lebanon | Grafton County | 15,646 |
| Litchfield | Hillsborough County | 8,855 |
| Littleton | Grafton County | 5,994 |
| Loudon | Merrimack County | 5,813 |
| Lee | Strafford County | 4,534 |
| Lancaster | Coos County | 3,217 |
| Lyndeborough | Hillsborough County | 1,751 |
| Lyme | Grafton County | 1,709 |
| Lincoln | Grafton County | 1,678 |
| Lisbon | Grafton County | 1,621 |
| Lempster | Sullivan County | 1,169 |
| Langdon | Sullivan County | 658 |
| Lyman | Grafton County | 576 |
| Landaff | Grafton County | 436 |