# List of counties in New Jersey

There are 21 counties in the U.S. state of New Jersey. These counties together contain 564 municipalities, or administrative entities composed of clearly defined territory; 253 boroughs, 52 cities, 15 towns, 240 townships, and 4 villages. In New Jersey, a county is a local level of government between the state and municipalities. County government in New Jersey includes a Board of County Commissioners, sheriff, clerk, and surrogate (responsible for uncontested and routine probate), all of which are elected officials. Counties organized under the Optional County Charter Law may also have an elected county executive. Counties traditionally perform state-mandated duties such as the maintenance of jails, parks, and certain roads. The site of a county's administration and courts is called the county seat.

## History

New Jersey was governed by two groups of proprietors as two distinct provinces, East Jersey and West Jersey, between 1674 and 1702. New Jersey's first counties were created as administrative districts within each province, with East Jersey split in 1675 into Bergen, Essex, Middlesex and Monmouth counties, while West Jersey's initial counties of Burlington and Salem date to 1681. The most recent county created in New Jersey is Union County, created in 1857 and named after the union of the United States when the Civil War was imminent. New Jersey's county names derive from several sources, though most of its counties are named after place names in England and prominent leaders in the colonial and revolutionary periods. Bergen County is the most populous county—as of the 2020 Census—with 955,732 people, while Salem County is the least populous with 64,837 people.

## New Jersey legislature representation

Until the 1960s, the New Jersey Senate had 21 representatives, one from each county regardless of population. In the wake of the 1964 decision by the Supreme Court of the United States in Reynolds v. Sims, establishing the one man, one vote principle that state legislative districts must be approximately equal in size, David Friedland filed suit in New Jersey Supreme Court on behalf of two union leaders, challenging a system under which each county was represented by a single member in the New Jersey Senate. The court ruled unanimously that the existing system was unconstitutional, ordered that interim measures be established by statute for the 1965 legislative elections, and ordered that the needed constitutional changes to restructure the New Jersey Legislature to be in compliance with "one man, one vote" requirements be in place before elections took place in 1967. The senate unilaterally—by internal rule, not by statute—enacted a proposal whereby each senator's vote would be weighted based on the population of the county represented, under which Cape May County's senator would receive one vote while the senator from Essex County would receive 19.1 votes, in direct relation to the ratio of residents between counties. The Supreme Court ruled unanimously that it was unconstitutional for the senate to adopt a weighted voting system unilaterally. In 1966, the constitution was amended to establish 40 districts statewide, each represented by one senator and two assembly members, without relation to county boundaries.

## FIPS code

The Federal Information Processing Standard (FIPS) code, used by the United States government to uniquely identify counties, is provided with each entry. FIPS codes are five-digit numbers; for New Jersey the codes start with 34 and are completed with the three-digit county code. The FIPS code for each county in the table links to census data for that county.

## List of counties

| County | FIPS code | County seat | Largest City | Est. | Formed from | Named for | Density (per mi$^2$) | Pop. | Area |
| Atlantic County | 001 | Mays Landing | Egg Harbor Township 47,842 | 1837 | Gloucester County | The Atlantic Ocean, which forms the county's eastern border | 497.53 | 279,114 | 561 sq mi (1,453 km$^2$) |
| Bergen County | 003 | Hackensack | Hackensack 46,030 | 1683 | One of four original counties created in East Jersey | Bergen, New Netherland settlement | 4,182.23 | 978,641 | 234 sq mi (606 km$^2$) |
| Burlington County | 005 | Mount Holly | Evesham Township 46,826 | 1694 | One of two original counties created in West Jersey | The old ancient name for an inland market near Bridlington, England | 590.70 | 475,515 | 805 sq mi (2,085 km$^2$) |
| Camden County | 007 | Camden | Cherry Hill 74,553 | 1844 | Gloucester County | Charles Pratt, 1st Earl Camden (1714–1794), an English supporter of the colonists during the American Revolution | 2,405.35 | 533,988 | 222 sq mi (575 km$^2$) |
| Cape May County | 009 | Cape May Court House | Lower Township 22,057 | 1692 | Burlington County | Cape May, named in turn for the 17th-century Dutch explorer Cornelius Jacobsen Mey, who explored and surveyed the Delaware Bay to the south of the county | 368.14 | 93,875 | 255 sq mi (660 km$^2$) |
| Cumberland County | 011 | Bridgeton | Vineland 60,780 | 1748 | Salem County | Prince William, Duke of Cumberland (1721–1765), second son of George II of Great Britain and military victor at the Battle of Culloden in 1746 | 318.36 | 155,678 | 489 sq mi (1,267 km$^2$) |
| Essex County | 013 | Newark | Newark 311,549 | 1683 | One of four original counties created in East Jersey | The county of Essex in England | 6,996.25 | 881,527 | 126 sq mi (326 km$^2$) |
| Gloucester County | 015 | Woodbury | Washington Township 48,677 | 1686 | Burlington County | The city of Gloucester, England | 959.33 | 311,783 | 325 sq mi (842 km$^2$) |
| Hudson County | 017 | Jersey City | Jersey City 292,449 | 1840 | Bergen County | The English explorer Henry Hudson (d. 1611), who explored portions of New Jersey's coastline | 15,663.51 | 736,185 | 47 sq mi (122 km$^2$) |
| Hunterdon County | 019 | Flemington | Raritan Township 23,447 | 1714 | Burlington County | Robert Hunter (1664–1734), the Colonial Governor of New Jersey from 1710 to 1720 | 306.30 | 131,708 | 430 sq mi (1,114 km$^2$) |
| Mercer County | 021 | Trenton | Hamilton Township 92,297 | 1838 | Burlington, Hunterdon, Middlesex, and Somerset counties | The Continental Army General Hugh Mercer (1726–1777), who died at the Battle of Princeton | 1,735.12 | 392,138 | 226 sq mi (585 km$^2$) |
| Middlesex County | 023 | New Brunswick | Edison 107,588 | 1683 | One of four original counties created in East Jersey | The historic county of Middlesex in England | 2,862.12 | 890,119 | 311 sq mi (805 km$^2$) |
| Monmouth County | 025 | Freehold Borough | Middletown Township 67,106 | 1683 | One of four original counties created in East Jersey | The historic County of Monmouth in Great Britain | 1,371.86 | 647,520 | 472 sq mi (1,222 km$^2$) |
| Morris County | 027 | Morristown | Parsippany-Troy Hills 56,162 | 1739 | Hunterdon County | Colonel Lewis Morris (1671–1746), colonial governor of New Jersey at the time of the county's formation | 1,115.25 | 523,053 | 469 sq mi (1,215 km$^2$) |
| Ocean County | 029 | Toms River | Lakewood Township 135,158 | 1850 | Monmouth and Burlington counties | The Atlantic Ocean, which forms the eastern border of New Jersey | 1,047.85 | 666,434 | 636 sq mi (1,647 km$^2$) |
| Passaic County | 031 | Paterson | Paterson 159,732 | 1837 | Bergen and Essex counties | Pasaeck, a Lenape word meaning "valley" | 2,846.47 | 526,597 | 185 sq mi (479 km$^2$) |
| Salem County | 033 | Salem | Pennsville Township 12,684 | 1694 | One of two original counties created in West Jersey | Salem, Biblical town, which takes its name from the Hebrew word for "peace." | 194.89 | 65,874 | 338 sq mi (875 km$^2$) |
| Somerset County | 035 | Somerville | Franklin Township 68,364 | 1688 | Middlesex County | The county of Somerset in England | 1,172.02 | 357,467 | 305 sq mi (790 km$^2$) |
| Sussex County | 037 | Newton | Vernon Township 22,358 | 1753 | Morris County | The county of Sussex in England | 283.00 | 147,444 | 521 sq mi (1,349 km$^2$) |
| Union County | 039 | Elizabeth | Elizabeth 137,298 | 1857 | Essex County | The union of the United States, which was being threatened by the dispute over slavery | 5,768.54 | 594,160 | 103 sq mi (267 km$^2$) |
| Warren County | 041 | Belvidere | Phillipsburg 15,249 | 1824 | Sussex County | The American Revolutionary War General Joseph Warren (1741–1775), killed at the Battle of Bunker Hill | 312.94 | 112,031 | 358 sq mi (927 km$^2$) |