County facts · Population · October 25, 2026
New Jersey Population by County, 2025 Census Estimates
New Jersey population by county: July 2025 Census estimates for all 21 counties, change since 2020, density, and a link to each official parcel map.
Looking for New Jersey population by county? The Census Bureau estimates that New Jersey had 9,548,215 residents on July 1, 2025, spread across 21 counties. Bergen County is the most populous, with 977,026 people (10% of the state), and Salem County is the least populous, with 66,280.
The table below lists every county with its 2025 estimate, its April 2020 starting point, the change, people per square mile, and a link to its official parcel viewer.
New Jersey population at a glance
- Counties: 21
- Statewide, July 1, 2025: 9,548,215 (April 1, 2020 estimates base: 9,289,024; change +259,191, +2.8%)
- Most populous: Bergen County (977,026); least populous: Salem County (66,280)
- Median county: about 481,439 residents (half of the counties are smaller)
- The 5 largest counties hold 44% of all New Jersey residents
- Counties with 1,000,000+ residents: 0 · 100,000+: 19 · under 10,000: 0
- Statewide density: about 1,298 people per square mile of land
New Jersey population by county, July 2025 (all 21)
Percent change runs from the April 1, 2020 estimates base to July 1, 2025. People per square mile is the July 2025 estimate divided by the county's land area in the Census Bureau's 2020 Gazetteer file, so lakes and bays are left out.
How New Jersey's population is spread out
Grouping the counties by size shows how concentrated the state is:
| Residents (July 2025) | Counties | Total residents | Share of state |
|---|---|---|---|
| 250,000 to 999,999 | 15 | 8,838,600 | 93% |
| 100,000 to 249,999 | 4 | 549,945 | 6% |
| 25,000 to 99,999 | 2 | 159,670 | 2% |
15 counties with at least 250,000 residents hold 93% of the state's population.
Most and least densely populated
The most crowded counties by people per square mile of land:
- Hudson County: 15,912 per sq mi (735,033 people on 46 sq mi)
- Essex County: 7,109 per sq mi (896,379 people on 126 sq mi)
- Union County: 5,857 per sq mi (601,863 people on 103 sq mi)
- Bergen County: 4,197 per sq mi (977,026 people on 233 sq mi)
- Passaic County: 2,858 per sq mi (531,624 people on 186 sq mi)
The most thinly settled:
- Salem County: 200 per sq mi (66,280 people on 332 sq mi)
- Sussex County: 285 per sq mi (148,063 people on 519 sq mi)
- Hunterdon County: 308 per sq mi (131,781 people on 428 sq mi)
- Warren County: 317 per sq mi (112,953 people on 357 sq mi)
- Cumberland County: 325 per sq mi (157,148 people on 483 sq mi)
About these numbers
- They are estimates. Between censuses the Census Bureau's Population Estimates Program updates county totals each year from births, deaths and migration records. The next full count is the 2030 census.
- The base is April 1, 2020. The estimates start from an April 1, 2020 "estimates base" built from the 2020 census, which is why it is slightly different from the published census count.
- Each new release revises the past. A newer vintage can change earlier years as well, so compare numbers from the same release, as this page does.
- Statewide total. The counties add up exactly to the statewide figure of 9,548,215 in the same file.
Using population numbers in a land search
- Big counties, busy offices. In the most populous counties, parcel maps and deed records are usually online and searchable, but recording and permit offices are busier. Allow for that if you are on a deadline.
- Small counties, fewer sales. In counties with only a few thousand people, land changes hands less often, so there are fewer recent sales to compare a price with. Recorded deeds and the local assessor's sales records are the best source.
- Density hints at lot size. A low people-per-square-mile figure usually means farms, ranches and timber tracts; a high one means subdivided lots. The parcel viewer shows the actual parcel lines.
- Check the official map. Use the parcel viewer link in the table for boundaries, parcel numbers and owner names, then confirm anything important with the local assessor and the office that records deeds.
Related guides
- Fastest growing counties in New Jersey
- Largest counties in New Jersey
- New Jersey county GIS websites by viewer
- Most populous counties in the US
- Where people are moving in the US
More: All New Jersey counties on Platbookmapper
Sources
- U.S. Census Bureau, Population Estimates Program, county totals, Vintage 2025 (April 1, 2020 estimates base and July 1, 2020–2025 estimates, with components of change). Statewide totals are the sum of the counties and match the file's state row.
- U.S. Census Bureau Gazetteer files, 2020 county land and water area (for people per square mile).
- Platbookmapper county GIS directory (live data file behind our county pages, pulled October 25, 2026) for each official parcel viewer.