Union County, New Jersey

Union County population, land area and income

Union County had 594,160 residents in the Census Vintage 2024 estimate, on 102.8 square miles of land. It ranks 7th of 21 in New Jersey by population and 20th by land area. That works out to 5,781.5 people per square mile, 60.1 times the US average of 96.3, and in the top tenth nationally.

The median county-equivalent in New Jersey has 475,515 residents; Union County is somewhat larger.

Its SAIPE 2023 median household income of $100,031 is in the top tenth among 3,143 counties with an estimate.

How Union County's population changed since 2020

Union County gained 20,480 residents between the July 2020 and July 2024 estimates, a rise of 3.6%. That ranks 3rd of 21 in New Jersey for growth. The median New Jersey county changed by +2.3%, and the state as a whole by +2.5%.

Since the April 2020 estimates base, Union County recorded 27,999 births and 19,111 deaths, a natural change of +8,888. Net international migration added +32,465 and net domestic migration, people moving to or from other US counties, came to -23,051. The largest single component was international migration, which added 32,465 people.

Where Union County is

The Census internal point of Union County is at 40.659900, -74.308700. It sits in UTM zone 18N. The map shades New Jersey's 21 county-equivalents by population change from 2020 to 2024, darker for faster growth, with Union County outlined. Dots are towns of 1,000+ people with residents in it.

Towns in Union County

13 incorporated places of 1,000+ people have residents in Union County, 408,708 people together, or 69% of the county. Each figure counts only the part of the town inside Union County; towns marked "part" extend into another county. The largest is Elizabeth with 140,413.

Counties bordering Union County

The Census 2024 county adjacency file lists 6 neighbors for Union County, including 1 across a state line. The most populous is Middlesex County, NJ, with 890,119 residents. Distances run between Census internal points in a straight line.

• Middlesex County

  890,119 people

  16 mi SSW

• Essex County

  881,527 people

  9 mi NNE

• Hudson County

  736,185 people

  13 mi ENE

• Morris County

  523,053 people

  19 mi NW

• NY

  Richmond County, NY

  498,212 people

  11 mi SE

• Somerset County

  357,467 people

  18 mi WSW

Distance to Trenton and the nearest big city

Trenton is 38.4 miles SW of Union County's internal point in a straight line. The nearest place of 100,000 or more is Elizabeth, NJ (population 140,413), 6.0 miles away. The nearest place of 10,000 or more is Westfield, NJ (population 32,050), 1.9 miles away.

Union County FIPS code

The FIPS code of Union County is 34039: state code 34 for New Jersey plus county code 039. Use it as text, with the leading zero, when joining Census, BLS, or CDC county tables. SAIPE lists its 2023 median household income as $100,031.