List of counties in New Jersey in the context of "Borough (New Jersey)"

New Jersey is a state located in both the Mid-Atlantic and Northeastern regions of the United States. Located at the geographic hub of the heavily urbanized Northeast megalopolis, it is bordered to the northwest, north, and northeast by New York State; on its east, southeast, and south by the Atlantic Ocean; on its west by the Delaware River and Pennsylvania; and on its southwest by Delaware Bay and Delaware. At 7,354 square miles (19,050 km), New Jersey is the fifth-smallest state in land area. According to a 2024 U.S. Census Bureau estimate, it is the 11th-most populous state, with over 9.5 million residents, its highest estimated count ever. The state capital is Trenton, and the state's most populous city is Newark. New Jersey is the only U.S. state in which every county is deemed urban by the U.S. Census Bureau. It is the most densely populated U.S. state.

New Jersey was first inhabited by Paleo-Indians as early as 13,000 BC. The Lenape were the dominant Indigenous group when Europeans arrived in the early 17th century, and they were subdivided into dialectal groups such as the Munsee, in the north, and the Unami and the Unalachtigo, elsewhere. Dutch and Swedish colonists founded the first European settlements in the state, with the British later seizing control of the region and establishing the Province of New Jersey, named after Jersey. The colony's fertile lands and relative religious tolerance drew a large and diverse population. New Jersey was among the Thirteen Colonies that supported the American Revolution, hosting several pivotal battles and military commands in the American Revolutionary War earning the title, "Crossroads of the American Revolution." New Jersey remained in the Union during the American Civil War and provided troops, resources, and military leaders in support of the Union Army. After the war, the state emerged as a major manufacturing center and a leading destination for immigrants, helping drive the Industrial Revolution in the U.S. New Jersey was the site of many industrial, technological, and commercial innovations. Many prominent Americans associated with New Jersey have proven influential nationally and globally, including in academia, advocacy, business, entertainment, government, military, non-profit leadership, and other fields.

Hudson County is a county in the U.S. state of New Jersey, its smallest and most densely populated. Lying in the northeast of the state and on the west bank of the Hudson River, the county is part of the state's Gateway Region and the New York metropolitan area. Its county seat is Jersey City, the county's largest city in terms of both population and area. Established in 1840, it is named for Henry Hudson, the sea captain who explored the area in 1609. The county is part of the North Jersey region of the state.

As of the 2020 United States census, the county was the state's fourth-most-populous and fastest-growing county in the previous decade, with a population of 724,854, its highest decennial count ever and an increase of 90,588 (+14.3%) from the 2010 census count of 634,266, which in turn reflected an increase of 25,291 (+4.2%) from the 2000 census population of 608,975. The United States Census Bureau's Population Estimates Program estimated a 2024 population of 736,185, an increase of 11,331 (+1.6%) from the 2020 decennial census.

Middlesex County is a county located in the north-central part of the U.S. state of New Jersey, extending inland from the Raritan Valley region to the northern portion of the Jersey Shore. As of the 2020 United States census, the county was the state's third-most populous county with a population of 863,162, its highest decennial count ever and an increase of 53,304 (+6.6%) from the 2010 census count of 809,858, which in turn reflected an increase of 59,696 (8.0%) from the 750,162 counted in the 2000 census. Middlesex is part of the New York metropolitan area. Many communities within the county serve as commuter towns to and from New York City and other points north. The county is part of the Central Jersey region of the state.

The county is located in the middle of the Northeast megalopolis of the U.S. Its county seat is the city of New Brunswick, a center for the sciences, arts, and cultural activities, and the headquarters of the state's flagship academic institution, Rutgers University. The county's most populous place, with 107,588 residents as of the 2020 census, is Edison, while Monroe Township covers the largest area of any municipality, at 42.19 square miles (109.3 km). Since the 2010 census, the state's center of population is in East Brunswick; the center of population for New Jersey has been in Middlesex County since the 1900 census. Middlesex County hosts an extensive transportation network, including several rail stations along the heavily traveled Northeast Corridor Line of the New Jersey Transit commuter rail system, as well as the intersection of the New Jersey Turnpike and the Garden State Parkway, the state's two busiest motor vehicle roadways, in Woodbridge Township. Middlesex County calls itself The Greatest County in the Land.

Monmouth County (/ˈmɒnməθ/) is a county located in the central portion of the U.S. state of New Jersey. It is bordered to its west by Mercer and Middlesex Counties, to its south by Ocean County, to its east by the Atlantic Ocean, and to its north by the Raritan Bay (sharing a border with the boroughs of Staten Island, Brooklyn, and Queens in New York City, across it). Monmouth County's geographic area comprises 30% water. The county is part of the Jersey Shore region of the state.

As of the 2020 United States census, the county was the state's fifth-most-populous county with a population of 643,615, its highest decennial count ever and an increase of 13,235 (+2.1%) from the 2010 census count of 630,380, which in turn reflected an increase of 15,079 from 615,301 at the 2000 census. As of 2010, the county fell to the fifth-most populous county in the state, having been surpassed by Hudson County. Monmouth's county seat is Freehold Borough, though many county offices are also located in neighboring Freehold Township. The most populous place was Middletown Township, with 67,106 residents at the time of the 2020 Census, while Howell Township covered 61.21 square miles (158.5 km), the largest total area of any municipality.

Ocean County is a county in the central part of the U.S. state of New Jersey, and the southernmost county in the New York metropolitan area. The county borders the Atlantic Ocean on the east and in terms of total area is the state's largest county. Its county seat is Toms River. The county is part of the Jersey Shore region of the state.

Since 2020, Ocean County has been the fastest-growing county in New Jersey, with a population of 637,229 recorded at the 2020 United States census, its highest decennial count ever and ranking the county as the state's sixth-most populous county, with an increase of 60,662 (+10.5%) from the 576,567 enumerated at the 2010 census, which in turn reflected an increase of 65,651 (+12.8%) from the 510,916 counted in the 2000 census. Since 2010, Ocean County's population has been growing faster than the United States as a whole. The United States Census Bureau's Population Estimates Program estimated a 2023 population of 659,197, an increase of 21,968 (+3.4%) from the 2020 decennial census. Ocean County’s most populous and fastest-growing place is Lakewood Township, with an estimated 139,866 residents as of 2023, while Jackson Township covers 100.62 square miles (260.6 km), the largest total area of any municipality in the county.

Atlantic County is a county in the southern part of the U.S. state of New Jersey. As of the 2020 census, the county was the state's 15th-most-populous county, with a population of 274,534, a drop of 15 from the 2010 census count of 274,549. The United States Census Bureau's Population Estimates Program estimated a 2024 population of 279,114, an increase of 4,580 (+1.7%) from the 2020 decennial census. Its county seat is the Mays Landing section of Hamilton Township. The county is part of the Jersey Shore region of the state.

The most populous place in Atlantic County is Egg Harbor Township, with 47,842 residents at the time of the 2020 census; Galloway Township, covered 115.21 square miles (298.4 km), the largest total area of any municipality, though Hamilton Township has the largest land area, covering 111.13 square miles (287.8 km). Atlantic County forms the Atlantic City–Hammonton metropolitan statistical area, which is also part of the Philadelphia metropolitan area.

Cape May County is the southernmost county in the U.S. state of New Jersey. Much of the county is located on the Cape May peninsula, bound by the Delaware Bay to its west and the Atlantic Ocean to its south and east. Adjacent to the Atlantic coastline are five barrier islands that have been built up as seaside resorts. A consistently popular summer destination with 30 miles (48 km) of beaches, Cape May County attracts vacationers from New Jersey and surrounding states, with the summer population exceeding 750,000. An estimated 11.6 million visitors in 2023 generated annual tourism spending of $7.7 billion, making it the county's single largest industry. The associated leisure and hospitality industries are Cape May's largest employers. Its county seat is the Cape May Court House section of Middle Township. The county is part of both the Jersey Shore and South Jersey regions of the state.

As of the 2020 United States census, the county was the state's second-least populous county, with a population of 95,263, a decrease of 2,002 (−2.1%) from the 2010 census count of 97,265, which in turn reflected a decline of 5,061 (-4.9%) from the 102,326 counted in the 2000 census. The United States Census Bureau's Population Estimates Program estimated a 2024 population of 93,875, a decrease of 1,388 (-1.5%) from the 2020 decennial census. The county is part of the Ocean City, NJ metropolitan statistical area and the Philadelphia-Reading-Camden, PA-NJ-DE-MD combined statistical area, also known as the Delaware Valley.