1850 Counties of New Hampshire
| County | Description | Area in sq miles | Courts held at | Pop in 1850 |
| Belknap | in easterly part, Lake Winnipisiogee on NE & Pemigewasset river on west. Winnipisiogee river crosses | 288 | Gilford | 17, 721 |
| Carroll | eastern boundary, with Squam & Winnipisiogee lakes on west & southwest | 550 | Ossipee | 20,157 |
| Cheshire | southwest corner, east side of Connecticut river | 442 | Keene | 28,344 |
| Coos | extreme north part, east side of Connecticut river | 1600 | Lancaster | 11,713 |
| Grafton | western boundary with Connecticut river on west | 1740 | Haverhill & Plymouth | 41,343 |
| Hillsborough | southern boundary, crossed by Merrimack river | 1245 | Amherst | 57,378 |