Middlesex is a borough in Middlesex County, in the U.S. state of New Jersey. It is located within the Raritan Valley region. As of the 2020 United States census, the borough's population was 14,636, its highest decennial count and an increase of 1,001 (+7.3%) from the 2010 census count of 13,635, which in turn reflected a decline of 82 (−0.6%) from the 13,717 counted in the 2000 census.Table 7. Population for the Counties and Municipalities in New Jersey: 1990, 2000 and 2010, New Jersey Department of Labor and Workforce Development, February 2011. Accessed May 1, 2023.

Middlesex was incorporated as a borough by an act of the New Jersey Legislature on April 9, 1913, from portions of Piscataway, based on the results of a referendum held on May 6, 1913.Snyder, John P. The Story of New Jersey's Civil Boundaries: 1606-1968, Bureau of Geology and Topography; Trenton, New Jersey; 1969. p. 170. Accessed May 30, 2024. The borough was named after Middlesex, England.Hutchinson, Viola L. The Origin of New Jersey Place Names, New Jersey Public Library Commission, May 1945. Accessed September 6, 2015.Gannett, Henry. The Origin of Certain Place Names in the United States, p. 207. United States Government Printing Office, 1905. Accessed September 6, 2015.

History The Harris Lane School was a one-room schoolhouse that was the oldest school in Middlesex County, dating back to its construction in the 1790s.Staff. , Courier News, April 25, 2000. Accessed August 6, 2013. The original Pierce School was known as the East Bound Brook School House and The Parker House was also used for education until it was converted into a two-family house. As the Borough grew new schools were constructed to accommodate many more students. Our Lady of Mt. Virgin School was the first parochial school built in 1954.

In 1905, the Lincoln section of Middlesex organized a volunteer fire company and that set the organization of four other fire companies in the borough.

Middlesex was a portion of Piscataway Township, until May 6, 1913, when it was incorporated as a separate entity through the action of the state legislature and local referendum. George Harris was elected as the first mayor and the first borough council was elected at the same time. Two constables were the law enforcement officers and were soon assisted by five appointed marshals.

Uranium processing and aftermath

Geography According to the United States Census Bureau, the borough had a total area of 3.51 square miles (9.09 km2), including 3.49 square miles (9.03 km2) of land and 0.02 square miles (0.06 km2) of water (0.63%).

Unincorporated communities, localities and place names located partially or completely within the borough include East Bound Brook and Lincoln.Locality Search, State of New Jersey. Accessed May 21, 2015.

The borough borders the Middlesex County municipalities of Dunellen and Piscataway Township in Middlesex County; and Bound Brook, Bridgewater Township, Green Brook Township and South Bound Brook in Somerset County.Areas touching Middlesex, MapIt. Accessed February 27, 2020.Municipalities, Middlesex County, New Jersey. Accessed December 1, 2019.New Jersey Municipal Boundaries, New Jersey Department of Transportation. Accessed November 15, 2019.

Middlesex is in the central division of the Raritan Valley (a line of cities in central New Jersey), along with Dunellen, Bound Brook, and South Bound Brook.

Demographics

2020 census As of the 2020 census, Middlesex had a population of 14,636. The median age was 40.2 years. 21.4% of residents were under the age of 18 and 15.3% of residents were 65 years of age or older. For every 100 females there were 92.7 males, and for every 100 females age 18 and over there were 92.9 males age 18 and over.

100.0% of residents lived in urban areas, while 0.0% lived in rural areas.

There were 5,302 households in Middlesex, of which 33.8% had children under the age of 18 living in them. Of all households, 53.6% were married-couple households, 15.2% were households with a male householder and no spouse or partner present, and 24.8% were households with a female householder and no spouse or partner present. About 21.6% of all households were made up of individuals and 10.8% had someone living alone who was 65 years of age or older.

There were 5,472 housing units, of which 3.1% were vacant. The homeowner vacancy rate was 0.8% and the rental vacancy rate was 3.1%.

+ Racial composition as of the 2020 census Race Number Percent White 8,841 60.4% Black or African American 968 6.6% American Indian and Alaska Native 77 0.5% Asian 1,176 8.0% Native Hawaiian and Other Pacific Islander 5 0.0% Some other race 1,826 12.5% Two or more races 1,743 11.9% Hispanic or Latino (of any race) 3,751 25.6%

2010 census The 2010 United States census counted 13,635 people, 4,984 households, and 3,633 families in the borough. The population density was 3,876.2 per square mile (1,496.6/km2). There were 5,148 housing units at an average density of 1,463.5 per square mile (565.1/km2). The racial makeup was 81.24% (11,077) White, 5.13% (699) Black or African American, 0.18% (24) Native American, 6.00% (818) Asian, 0.07% (10) Pacific Islander, 5.37% (732) from other races, and 2.02% (275) from two or more races. Hispanic or Latino of any race were 16.47% (2,246) of the population.

Of the 4,984 households, 32.0% had children under the age of 18; 56.0% were married couples living together; 11.8% had a female householder with no husband present and 27.1% were non-families. Of all households, 22.2% 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 2.73 and the average family size was 3.22.

22.5% of the population were under the age of 18, 8.1% from 18 to 24, 26.1% from 25 to 44, 29.5% from 45 to 64, and 13.8% who were 65 years of age or older. The median age was 40.7 years. For every 100 females, the population had 93.9 males. For every 100 females ages 18 and older there were 91.8 males.

The Census Bureau's 2006–2010 American Community Survey showed that (in 2010 inflation-adjusted dollars) median household income was $80,338 (with a margin of error of +/− $7,790) and the median family income was $93,817 (+/− $13,746). Males had a median income of $55,248 (+/− $7,439) versus $46,447 (+/− $5,086) for females. The per capita income for the borough was $34,607 (+/− $3,321). About 0.6% of families and 2.1% of the population were below the poverty line, including 1.6% of those under age 18 and 4.6% of those age 65 or over.DP03: Selected Economic Characteristics from the 2006-2010 American Community Survey 5-Year Estimates for Middlesex borough, Middlesex County, New Jersey , United States Census Bureau. Accessed September 4, 2012.

2000 census As of the 2000 United States census there were 13,717 people, 5,048 households, and 3,740 families residing in the borough. The population density was . There were 5,130 housing units at an average density of . The racial makeup of the borough was 87.26% White, 3.36% African American, 0.13% Native American, 4.16% Asian, 0.02% Pacific Islander, 3.21% from other races, and 1.86% from two or more races. Hispanic or Latino of any race were 9.00% of the population.Census 2000 Profiles of Demographic / Social / Economic / Housing Characteristics for Middlesex borough, New Jersey , United States Census Bureau. Accessed September 4, 2012.DP-1: Profile of General Demographic Characteristics: 2000 - Census 2000 Summary File 1 (SF 1) 100-Percent Data for Middlesex borough, Middlesex County, New Jersey , United States Census Bureau. Accessed September 4, 2012.

There were 5,048 households, out of which 34.1% had children under the age of 18 living with them, 59.3% were married couples living together, 10.5% had a female householder with no husband present, and 25.9% were non-families. 21.7% of all households were made up of individuals, and 10.7% had someone living alone who was 65 years of age or older. The average household size was 2.71 and the average family size was 3.17.

In the borough the population was spread out, with 24.1% under the age of 18, 6.2% from 18 to 24, 32.3% from 25 to 44, 23.2% from 45 to 64, and 14.2% who were 65 years of age or older. The median age was 38 years. For every 100 females, there were 95.0 males. For every 100 females age 18 and over, there were 91.9 males.

The median income for a household in the borough was $60,723, and the median income for a family was $70,343. Males had a median income of $47,446 versus $34,232 for females. The per capita income for the borough was $27,834. About 2.4% of families and 3.6% of the population were below the poverty line, including 4.1% of those under age 18 and 2.3% of those age 65 or over. Government

Local government

Middlesex is governed under the borough form of New Jersey municipal government, which is used in 218 municipalities (of the 564) statewide, making it the most common form of government in New Jersey.Inventory of Municipal Forms of Government in New Jersey, Rutgers University Center for Government Studies, July 1, 2011. Accessed June 1, 2023. The governing body is comprised of a mayor and a borough council, with all positions elected at-large on a partisan basis as part of the November general election. A mayor is elected directly by the voters to a four-year term of office. The borough council includes six members elected to serve three-year terms on a staggered basis, with two seats coming up for election each year in a three-year cycle.2012 New Jersey Legislative District Data Book, Rutgers University Edward J. Bloustein School of Planning and Public Policy, March 2013, p. 98. The borough form of government used by Middlesex is a "weak mayor / strong council" government in which council members act as the legislative body with the mayor presiding at meetings and voting only in the event of a tie. The mayor can veto ordinances subject to an override by a two-thirds majority vote of the council. The mayor makes committee and liaison assignments for council members, and most appointments are made by the mayor with the advice and consent of the council.Cerra, Michael F. "Forms of Government: Everything You've Always Wanted to Know, But Were Afraid to Ask", New Jersey State League of Municipalities, March 2007. Accessed January 1, 2025."Forms of Municipal Government in New Jersey", p. 6. Rutgers University Center for Government Studies. Accessed June 1, 2023.

The seven-member governing body is empowered to enact local ordinances, to levy municipal taxes and conduct the affairs of the community. In almost all cases, it can review and approve the actions of other Middlesex Borough committees and agencies. The mayor and Borough Council conduct all of their business during monthly meetings open to the public. All legislative powers of the borough are exercised by the mayor and council. These powers can take the form of a resolution, ordinance or proclamation.

, the mayor of Middlesex is Republican John "Jack" Mikolajczyk, whose term of office ends December 31, 2027. Members of the Middlesex Borough Council are Council President Michael Conahan (R, 2026), Jennifer Clock (R, 2028), Joseph DeScenza (R, 2027), Kevin Dotey (R, 2026), Kenneth Griggs Jr. (R, 2027) and Shannon Quinn (R, 2028)).Mayor and Council, Borough of Middlesex. Accessed January 31, 2026.2025 Municipal Data Sheet, Borough of Middlesex. Accessed January 31, 2026.November 4, 2025 General Election Official Results, Middlesex County, New Jersey, updated November 20, 2025. Accessed January 1, 2026.Tuesday, November 5 General Election Official Results, Middlesex County, New Jersey, updated November 27, 2024. Accessed January 1, 2025.November 7, 2023 General Election Official Results, Middlesex County, New Jersey, December 7, 2023. Accessed January 1, 2024.