[22] 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.

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.

[1][2] Unincorporated communities, localities and place names located partially or completely within the borough include East Bound Brook and Lincoln.

The 2010 United States census counted 13,635 people, 4,984 households, and 3,633 families in the borough.

[36] As of the 2000 United States census[17] there were 13,717 people, 5,048 households, and 3,740 families residing in the borough.

[7] 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.

[38][39] 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.

As of 2024[update], the mayor of Middlesex is Republican John "Jack" Mikolajczyk, whose term of office ends December 31, 2023.

[3][40][41][42][43] In July 2022, the borough council appointed Michael Conahan to fill the seat expiring in December 2023 that had been held by Amy Flood.

[42] In January 2020, the borough council appointed Amy Flood to fill the seat expiring in December 2020 that was vacated by John L. Madden when he took office as mayor.

[44][45] Until his selection in early 2006 to serve as borough administrator, Ron Dobies had been one of the longest-tenured mayors in New Jersey, with 26 years of service to Middlesex.

[48] For the 119th United States Congress, New Jersey's 12th congressional district is represented by Bonnie Watson Coleman (D, Ewing Township).

[51] For the 2024-2025 session, the 21st legislative district of the New Jersey Legislature is represented in the State Senate by Jon Bramnick (R, Westfield) and in the General Assembly by Michele Matsikoudis (R, New Providence) and Nancy Munoz (R, Summit).

[53] As of 2025[update], Middlesex County's Commissioners (with party affiliation, term-end year, and residence listed in parentheses) are: Director Ronald G. Rios (D, Carteret, 2027),[54] Deputy Director Shanti Narra (D, North Brunswick, 2027),[55] Claribel A.

[82] The Middlesex Board of Education serves public school students in pre-kindergarten through twelfth grade.

[97][98] Mountain View Park is a large open space in the center of the borough.

The statue of Abraham Lincoln by Alfonso Pelzer, his original work which was copied after his death, was installed in the park in 1898.

[citation needed] People who were born in, residents of, or otherwise closely associated with Middlesex include: