List of New Hampshire counties

1. Belknap County: formed in 1840 from parts of Merrimack County and Strafford County. County seat: Laconia.
2. Carroll County: formed in 1840 from part of Strafford County. County seat: Ossipee.
3. Cheshire County: one of five original counties created in New Hampshire in 1769. County seat: Keene.
4. Coos County: formed in 1803 from part of Grafton County. County seat: Lancaster.
5. Grafton County: one of five original counties created in New Hampshire in 1769. County seat: Haverhill.
6. Hillsborough County: one of five original counties created in New Hampshire in 1769. County seats: Nashua and Manchester.
7. Merrimack County: formed in 1827 from parts of Hillsborough County and Rockingham County. County seat: Concord.
8. Rockingham County: one of five original counties created in New Hampshire in 1769. County seat: Brentwood. (Exeter was the county seat until 1997.)
9. Strafford County: one of five original counties created in New Hampshire in 1769. County seat: Dover.
10. Sullivan County: formed in 1827 from part of Cheshire County. County seat: Newport.