[22] Northfield was founded by Jeremiah Leeds; he has a gravestone at Oxford Circle, but it is not certain that he was buried there.

[23] Northfield was incorporated as a city by an act of the New Jersey Legislature on March 21, 1905, from portions of Egg Harbor Township.

[26][27] Geographically, the city, and all of Atlantic County, is part of the South Jersey region of the state and of the Atlantic City-Hammonton metropolitan statistical area, which in turn is included in the Philadelphia-Reading-Camden combined statistical area and the Delaware Valley.

[2][3] Unincorporated communities, localities and place names located partially or completely within the city include Bakersville and Dolphin.

[29] The borough borders the Atlantic County municipalities of Egg Harbor Township, Linwood and Pleasantville.

[40] As of the 2000 United States census[17] there were 7,725 people, 2,824 households, and 2,109 families residing in the city.

[38][39] Northfield is home to Birch Grove Park, which covers 271 acres (110 ha) of heavily wooded land dotted with stocked fresh water fishing lakes.

Birch Grove Park features over 50 campsites, exercise and nature trails, a bandstand and an extensive children's playground.

[41] Northfield features a large bird sanctuary, dedicated to remaining open space in perpetuity.

Under this form of government, the council functions as a legislative body: it passes ordinances and approves the appointments of the mayor.

[51] In the November 2014 general election, Republican Erland Chau was chosen to fill the balance of the mayoral seat expiring December 31, 2015.

[55] Among the township's 2010 Census population, 65.1% (vs. 58.8% in Atlantic County) were registered to vote, including 85.9% of those ages 18 and over (vs. 76.6% countywide).

[71][72][73] For the 119th United States Congress, New Jersey's 2nd congressional district is represented by Jeff Van Drew (R, Dennis Township).

[75] For the 2024-2025 session, the 2nd legislative district of the New Jersey Legislature is represented in the New Jersey Senate by Vincent J. Polistina (R, Egg Harbor Township) and in the General Assembly by Don Guardian (R, Atlantic City) and Claire Swift (R, Margate City).

[77][78] As of 2025[update], Atlantic County's Executive is Dennis Levinson (R, Northfield), whose term of office ends December 31, 2027.

[107] City public school students are also eligible to attend the Atlantic County Institute of Technology in the Mays Landing section of Hamilton Township[108] or the Charter-Tech High School for the Performing Arts, located in Somers Point.

[111] U.S. Route 9 is the main highway directly serving Northfield, running south into Linwood and north into Pleasantville.

These major highways provide connections to New York City, Philadelphia and Cape May.