Chester Township was established by an Act of the New Jersey Legislature on April 1, 1799 from portions of both Roxbury Township and Washington Township, based on the results of a referendum held that day. Additional territories were acquired from Randolph Township (in 1806) and Washington Township (1840 and 1853). Portions of the township were taken on April 3, 1930 to form Chester Borough, a separate municipality surrounded entirely by Chester Township.
As of the census of 2000, there were 7,282 people, 2,323 households, and 2,014 families residing in the township. The population density was 248.3 people per square mile (95.9/km²). There were 2,377 housing units at an average density of 81.1/sq mi (31.3/km²). The racial makeup of the township was 95.12% white, 1.15% African American, 0.01% Native American, 2.39% Asian, 0.05% Pacific Islander, 0.26% from other races, and 1.00% from two or more races. Hispanic or Latino of any race were 2.58% of the population.
Of the 2,323 households, 46.0% feature children under the age of 18, 79.6% were married couples living together, 4.9% had a female householder with no husband present, and 13.3% were non-families. 10.3% of all households were made up of individuals and 3.0% had someone living alone who was 65 years of age or older. The average household size was 3.05 and the average family size was 3.29.
In the township the population was spread out with 30.5% under the age of 18, 4.1% from 18 to 24, 26.5% from 25 to 44, 29.8% from 45 to 64, and 9.1% who were 65 years of age or older. The median age was 40 years. For every 100 females there were 97.0 males. For every 100 females age 18 and over, there were 93.8 males.
The median income for a household in the township was $117,298, and the median income for a family was $133,586. Males had a median income of $91,841 versus $52,076 for females. The per capita income for the township was $55,353. About 2.4% of families and 2.3% of the population were below the poverty line, including 1.8% of those under age 18 and 2.8% of those age 65 or over.
New Jersey Transit local bus service is provided on the MCM4 and MCM5 routes.