New Jersey Counties, Demographics & Geography
Complete official guide to all 21 counties in New Jersey (NJ). Explore 2024 US Census population estimates, county seats, FIPS codes, land areas, and interactive mapping tools powered by GeoMap Suite.
New Jersey County Breakdown
Showing 11 of 11 documented counties and seats.
County Name | FIPS | County Seat | Population (Census) | Land Area | Quick Tool |
|---|---|---|---|---|---|
| Bergen County | 34003 | Hackensack | 955,732 | 233 sq mi | Lookup |
| Essex County (Newark) | 34013 | Newark | 863,728 | 126 sq mi | Lookup |
| Middlesex County | 34023 | New Brunswick | 863,162 | 309 sq mi | Lookup |
| Hudson County (Jersey City) | 34017 | Jersey City | 724,854 | 46 sq mi | Lookup |
| Monmouth County | 34025 | Freehold Borough | 643,615 | 469 sq mi | Lookup |
| Ocean County | 34029 | Toms River | 637,229 | 628 sq mi | Lookup |
| Union County | 34039 | Elizabeth | 575,345 | 103 sq mi | Lookup |
| Passaic County (Paterson) | 34031 | Paterson | 524,118 | 185 sq mi | Lookup |
| Camden County | 34007 | Camden | 523,485 | 221 sq mi | Lookup |
| Morris County | 34027 | Morristown | 509,285 | 460 sq mi | Lookup |
| Mercer County (Trenton) | 34021 | Trenton | 387,340 | 225 sq mi | Lookup |
Geographic Structure of New Jersey Counties
County Administration & Governance
In New Jersey, county governments manage vital public infrastructure, tax assessments, law enforcement, judicial courts, election administration, and public records. The county seat (Hackensack and other municipal headquarters) houses the primary courthouse, commissioners, and sheriff’s department.
All New Jersey counties carry a unique 5-digit Federal Information Processing Standard (FIPS) code, where the first two digits (34) designate the state and the remaining three digits identify each specific jurisdiction.
Geographic & Demographic Highlights
- Most Populous County:Bergen County (955,732 residents)
- Largest by Land Area:Ocean County (628 sq mi)
- State Capital:Trenton
- 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.