New Hampshire Counties Directory & Interactive Map
Complete official guide to all 10 counties in New Hampshire (NH). Explore 2024 US Census population estimates, county seats, FIPS codes, land areas, and interactive mapping tools powered by GeoMap Suite.
New Hampshire County Breakdown
Showing 6 of 6 documented counties and seats.
County Name | FIPS | County Seat | Population (Census) | Land Area | Quick Tool |
|---|---|---|---|---|---|
| Hillsborough County (Manchester/Nashua) | 33011 | Manchester / Nashua | 422,937 | 876 sq mi | Lookup |
| Rockingham County | 33015 | Brentwood | 314,176 | 699 sq mi | Lookup |
| Merrimack County (Concord) | 33013 | Concord | 153,808 | 934 sq mi | Lookup |
| Strafford County (Dover) | 33017 | Dover | 130,889 | 369 sq mi | Lookup |
| Grafton County | 33009 | Haverhill | 91,118 | 1,714 sq mi | Lookup |
| Cheshire County (Keene) | 33005 | Keene | 76,458 | 708 sq mi | Lookup |
Geographic Structure of New Hampshire Counties
County Administration & Governance
In New Hampshire, county governments manage vital public infrastructure, tax assessments, law enforcement, judicial courts, election administration, and public records. The county seat (Manchester / Nashua and other municipal headquarters) houses the primary courthouse, commissioners, and sheriff’s department.
All New Hampshire counties carry a unique 5-digit Federal Information Processing Standard (FIPS) code, where the first two digits (33) designate the state and the remaining three digits identify each specific jurisdiction.
Geographic & Demographic Highlights
- Most Populous County:Hillsborough County (Manchester/Nashua) (422,937 residents)
- Largest by Land Area:Grafton County (1,714 sq mi)
- State Capital:Concord
- Census Bureau Region:Northeast United States
Demographic calculations derive from the United States Census Bureau 2024 Population Estimates Program (PEP) and TIGER/Line geographic boundary files.