Cumberland County is a coastal county located on the Delaware Bay in the Southern Shore Region of the U.S. state of New Jersey. As of the 2020 census, the county was the state's 16th-most-populous county, with a population of 154,152, a decrease of 2,746 (−1.8%) from the 2010 census count of 156,898. Its county seat is Bridgeton. Cumberland County is named for Prince William, Duke of Cumberland. The county was formally created from portions of Salem County on January 19, 1748. The county is part of the South Jersey region of the state.

The most populous municipality is Vineland, which had a 2020 population of 60,780; the largest municipality by area is Maurice River Township, which covered 95.76 square miles (248.0 km).

This county is part of the Vineland-Bridgeton metropolitan statistical area, as well as the Delaware Valley Combined Statistical Area.

The county is named for Prince William, Duke of Cumberland who is best remembered for his role in putting down the Jacobite Rising at the Battle of Culloden in 1746, which made him immensely popular throughout parts of Britain.

The first people to populate Cumberland County were early descendants of the Lenape, also known as the Delaware, who include all Native American people who have lived in New Jersey Water sources such as the Cohansey River and Maurice River made Cumberland County a resourceful environment for early native groups to utilize. Archaeological materials such as stone tools and pottery have been excavated in sites in Bridgeton and in Fairfield, Greenwich and Stow Creek townships. Some of the earliest cultures that inhabited Cumberland County utilized clovis spear points which date to the Paleoindian period (10,000 BC to 8000 BC). As the climate switched from a tundra to woodlands during the archaic period (8000 BC to 1000 BC), ancestors of the Lenape developed axe technology, and later pottery during the woodland period (1000 BC to 1600 AD). The prehistoric period ended when European exploration and settlement arrived in the area bringing with it greater technology which ultimately supplanted much of the Native populations. Today, many Lenape people still reside in Cumberland County, such as the Nanticoke tribe who make up the Native American people from Southern New Jersey and the Delmarva Peninsula.

Early European settlement began with the Swedish who called what is now New Jersey New Sweden during the first half of the 17th century. Prior to the United States gaining its independence from Great Britain, Cumberland County was deemed separate from Salem County in 1748 and was named after the Duke of Cumberland. Cumberland County's economic exploits were agricultural and manufacturing, more specifically the county focused on fruits and vegetables, as well as glassware and preserved foods.

America's early successes in glassmaking began in Southern New Jersey during the 18th century and eventually led to John Landis Mason of Vineland New Jersey to invent the mason jar for storing and preserving food at home during the 1850s. Cumberland County's population has historically been "majority-minority". Cumberland County went from holding one hundred and twenty enslaved people in 1790, to two by 1830. Cumberland County included several towns settled by Black Americans many of whom escaped slavery. Parts of the county were used for the Underground Railroad, and housed Harriet Tubman and William Still.

In addition to agriculture and glassware, Cumberland County is known for its maritime industries. Its main maritime export was oysters until the 1950s when disease destroyed the oyster population. With the oyster industry came shipbuilding in 1780. Later, the industrial revolution and railroad development increased the number of ships and the types of ships being made. By the late 19th century, ships switched from the sloop model to the schooner to be more useful for oystering.

Whaling was also an industry in Cumberland County until 1775 when settlers turned to livestock, farming, and trapping. Caviar was a short-lived industry in the area from the 1860s to 1925, when sturgeon had been overfished. There are 19th and 20th century maritime related artifacts such as ship models, building plans, tools, and rigging equipment at the John Dubois Maritime Museum in Bridgeton.

According to the U.S. Census Bureau, as of the 2020 Census, the county had a total area of 677.85 square miles (1,755.6 km), of which 483.36 square miles (1,251.9 km) was land (71.3%) and 194.49 square miles (503.7 km) was water (28.7%). Cumberland is a low-lying, generally featureless coastal county, with many salt marshes near the Delaware Bay. The highest elevation is at one of 12 areas in Upper Deerfield Township that stand approximately 140 feet (43 m) above sea level; the lowest elevation is sea level.

Bridgeton, New Jersey
Climate chart (explanation)
J F M A M J J A S O N D     3.6     41 25     2.9     44 28     4.3     52 34     4     63 43     3.8     73 53     4.2     82 63     4.1     87 68     4.1     85 66     4.3     78 59     3.6     67 47     3.3     56 39     4     45 30 █ Average max. and min. temperatures in °F █ Precipitation totals in inches Source: The Weather Channel
Metric conversion J F M A M J J A S O N D     90     5 −4     75     7 −2     109     11 1     102     17 6     95     23 12     107     28 17     103     31 20     104     29 19     108     26 15     91     19 8     83     13 4     101     7 −1 █ Average max. and min. temperatures in °C █ Precipitation totals in mm

In recent years, average temperatures in the county seat of Bridgeton have ranged from a low of 25 °F (−4 °C) in January to a high of 87 °F (31 °C) in July, although a record low of −13 °F (−25 °C) was recorded in January 1985 and a record high of 101 °F (38 °C) was recorded in July 1966. Average monthly precipitation ranged from 2.94 inches (75 mm) in February to 4.30 inches (109 mm) in March. Cumberland has a humid subtropical climate (Cfa).

Historical population

Census	Pop.	Note	%±
1790	8,248		—
1800	9,529		15.5%
1810	12,670		33.0%
1820	12,668		0.0%
1830	14,093		11.2%
1840	14,374		2.0%
1850	17,189		19.6%
1860	22,605		31.5%
1870	34,665		53.4%
1880	37,687		8.7%
1890	45,438		20.6%
1900	51,193		12.7%
1910	55,153		7.7%
1920	61,348		11.2%
1930	69,895		13.9%
1940	73,184		4.7%
1950	88,597		21.1%
1960	106,850		20.6%
1970	121,374		13.6%
1980	132,866		9.5%
1990	138,053		3.9%
2000	146,438		6.1%
2010	156,898		7.1%
2020	154,152		−1.8%
2023 (est.)	152,326		−1.2%
Historical sources: 1790-1990 1970-2010 2010 2020

As of the 2020 United States census, the county's had 154,152 people, 51,360 households, and 34,309 families. The population density was 318.7 inhabitants per square mile (123.1/km). There were 57,119 housing units at an average density of 118 per square mile (45.6/km). The racial makeup was 45.4% White, 18.0% African American, 0.9% Native American, 1.2% Asian, and 2.6% from two or more races. Hispanic or Latino of any race were 34.4% of the population.

Of the 51,360 households, of which 26.8% had children under the age of 18 living with them, 38.9% were married couples living together, 18.4% had a female householder with no husband present, 9.3% had a male householder with no wife present and 33.2% were non-families, and 12.1% had someone living alone who was 65 years of age or older. The average household size was 2.68 and the average family size was 3.30.

About 23.8% of the population was under age 18, 7.5% was from age 18 to 24, 39.3% was from age 15 to 44, and 15.7% was age 65 or older. The median age was 38.1 years. The gender makeup was 51.7% male and 48.3% female. For every 100 females, there were 107.1 males.

The median household income was $54,587, and the median family income was $65,022. About 13.2% of the population were below the poverty line, including 17.1% of those under age 18 and 10.4% of those age 65 or over.

The 2010 United States census counted 156,898 people, 51,931 households, and 36,559 families in the county. The population density was 324.4 inhabitants per square mile (125.3/km). There were 55,834 housing units at an average density of 115.4 per square mile (44.6/km). The racial makeup was 62.74% (98,430) White, 20.23% (31,741) Black or African American, 1.11% (1,746) Native American, 1.22% (1,907) Asian, 0.04% (59) Pacific Islander, 11.15% (17,492) from other races, and 3.52% (5,523) from two or more races. Hispanic or Latino of any race were 27.06% (42,457) of the population.

Of the 51,931 households, 31.4% had children under the age of 18; 45.2% were married couples living together; 18.6% had a female householder with no husband present and 29.6% were non-families. Of all households, 24% were made up of individuals and 10.8% had someone living alone who was 65 years of age or older. The average household size was 2.79 and the average family size was 3.26.

Of the population, 24% were under the age of 18, 9.5% from 18 to 24, 28.5% from 25 to 44, 25.3% from 45 to 64, and 12.6% who were 65 years of age or older. The median age was 36.5 years. For every 100 females, the population had 106.2 males. For every 100 females ages 18 and older there were 106.9 males.

The Bureau of Economic Analysis calculated that the county's gross domestic product was $5.9 billion in 2021, which was ranked 17th in the state and was a 3.8% increase from the prior year.

Cumberland County is governed by a Board of County Commissioners which is comprised of seven members who are elected at large by the citizens of Cumberland County in partisan elections and serve staggered three-year terms in office, with either two or three seats coming up for election each year in a three-year cycle. Each Commissioner is assigned responsibility for one of the county's departments. In 2016, freeholders were paid $15,000 and the freeholder director was paid an annual salary of $16,000.

As of 2025, members of the Cumberland County Board of County Commissioners (with party affiliation, residence, and term-end year listed in parentheses) are (with terms for director and deputy director ending every December 31):

Commissioner	Party, Residence, Term
Robert A. Austino	D, Bridgeton, 2027
Deputy Director Antonio Romero	R, Vineland, 2027
Douglas A. Albrecht	R, Vineland, 2025
Victoria Groetsch-Lods	R, Vineland, 2025
Arthur Marchand	R, Hopewell Township, 2026
James Sauro	R, Vineland, 2026
Sandra Taylor	R, Downe Township, 2026

Pursuant to Article VII Section II of the New Jersey State Constitution, each county in New Jersey has have three elected administrative officials known as "constitutional officers." These officers are the County Clerk and County Surrogate (both elected for five-year terms of office) and the County Sheriff (elected for a three-year term). The county's constitutional officers are:

Title	Representative
County Clerk	Celeste Riley (D, Bridgeton, 2029),
Sheriff	Michael Donato (R, Bridgeton, 2026)
Surrogate	Rudolph A. Luisi (R, Vineland, 2028).

The Cumberland County Prosecutor is Jennifer Webb-McRae of Vineland. First nominated by Governor of New Jersey Jon Corzine in January 2010, Webb-McRae was nominated for a second five-year term by Chris Christie in November 2016 and sworn into office after confirmation in January 2017. Cumberland County is a part of Vicinage 15 of the New Jersey Superior Court (along with Gloucester County and Salem County), seated in Woodbury in Gloucester County; the Assignment Judge for the vicinage is Benjamin C. Telsey. The Cumberland County Courthouse is in Bridgeton.

In January 2023, John P. Capizola Jr. was appointed to fill the commissioner seat expiring in December 2023 that had been held by George Castellini until he resigned from office earlier that month.

New Jersey's 2nd congressional district includes all of Cumberland County. For the 118th United States Congress, New Jersey's 2nd congressional district is represented by Jeff Van Drew (R, Dennis Township).

The 14 municipalities of Cumberland County are part of two legislative districts.

District	Senate	Assembly	Municipalities
1st	Mike Testa (R)	Antwan McClellan (R) Erik K. Simonsen (R)	Bridgeton, Commercial Township, Downe Township, Fairfield Township, Lawrence Township, Maurice River Township, Millville, and Vineland. The remainder of this district includes portions of Atlantic County & Cape May County.
3rd	John Burzichelli (D)	Heather Simmons (D) Dave Bailey (D)	Deerfield Township, Greenwich Township, Hopewell Township, Shiloh Borough, Stow Creek, Upper Deerfield Township. The remainder of this district includes portions of Gloucester County & Salem County.

The New Jersey Department of Corrections operates three correctional facilities in the county: Bayside State Prison, South Woods State Prison, and Southern State Correctional Facility. The three facilities employ 1,500 people and house one of every three state prisoners. In 2007, while the state was preparing to close Riverfront State Prison in Camden, it considered establishing a fourth state prison in Cumberland County.

Cumberland County tends to be a swing county with Republicans holding most countywide and state legislative offices, as well as the one congressional district that covers the county. Since 1936, the county has voted for the national winner of the presidential election all but five times, however, in 2024, the county voted Republican for the first time since 1988. As of April 1, 2024 there were a total of 96,165 registered voters in Cumberland County, of whom 31,945 (33.2%) were registered as Democrats, 23,867 (24.8%) were registered as Republicans, and 38,531 (40.1%) were registered as unaffiliated. There were 1,822 voters (1.9%) registered to other parties.

United States presidential election results for Cumberland County, New Jersey

Year	Republican		Democratic		Third party(ies)
	No.	%	No.	%	No.	%
2024	28,675	51.25%	26,577	47.50%	700	1.25%
2020	28,952	46.27%	32,742	52.32%	881	1.41%
2016	24,453	45.01%	27,771	51.11%	2,107	3.88%
2012	20,658	37.31%	34,055	61.51%	656	1.18%
2008	22,360	38.42%	34,919	60.00%	915	1.57%
2004	24,362	45.81%	27,875	52.41%	948	1.78%
2000	18,882	38.78%	28,188	57.90%	1,614	3.32%
1996	14,744	31.69%	25,444	54.68%	6,345	13.64%
1992	19,253	36.94%	22,220	42.64%	10,643	20.42%
1988	26,024	53.83%	21,869	45.23%	456	0.94%
1984	29,398	57.47%	21,141	41.33%	616	1.20%
1980	23,242	50.09%	19,356	41.71%	3,805	8.20%
1976	20,535	40.84%	29,165	58.00%	587	1.17%
1972	26,409	58.18%	18,692	41.18%	291	0.64%
1968	18,388	40.42%	21,661	47.62%	5,439	11.96%
1964	12,611	27.29%	33,593	72.69%	11	0.02%
1960	21,283	47.81%	23,199	52.12%	30	0.07%
1956	24,067	58.07%	17,309	41.76%	68	0.16%
1952	21,819	53.40%	18,929	46.33%	111	0.27%
1948	16,556	51.24%	15,195	47.02%	562	1.74%
1944	14,477	47.91%	15,674	51.87%	67	0.22%
1940	16,322	45.75%	19,251	53.95%	107	0.30%
1936	14,500	41.09%	20,492	58.06%	300	0.85%
1932	16,668	55.61%	12,371	41.28%	932	3.11%
1928	23,921	77.92%	6,694	21.81%	84	0.27%
1924	15,691	71.05%	4,780	21.64%	1,613	7.30%
1920	11,913	68.36%	4,487	25.75%	1,027	5.89%
1916	5,692	52.14%	4,573	41.89%	652	5.97%
1912	1,895	18.18%	3,858	37.01%	4,671	44.81%
1908	6,770	56.56%	4,521	37.77%	679	5.67%
1904	7,402	64.28%	3,317	28.81%	796	6.91%
1900	6,780	58.65%	4,036	34.91%	744	6.44%
1896	7,018	61.09%	3,877	33.75%	593	5.16%