Clinton was incorporated as a town by an Act of the New Jersey Legislature on April 5, 1865, within portions of Clinton, Franklin and Union Townships. Clinton gained full independence from its three parent townships in 1895.
The State of New Jersey's Edna Mahan Correctional Facility for Women is located in Clinton, next to Hunterdon Developmental Center. It is perhaps best known for its Red Mill which sits on the banks of the south branch of the Raritan River and the Stone Mill which acts as an art museum.
As of the census of 2000, there were 2,632 people, 1,068 households, and 724 families residing in the town. The population density was 1,916.0 people per square mile (741.8/km²). There were 1,095 housing units at an average density of 797.1/sq mi (308.6/km²). The racial makeup of the town was 92.06% White, 1.33% African American, 0.46% Native American, 3.72% Asian, 1.37% from other races, and 1.06% from two or more races. Hispanic or Latino of any race were 4.10% of the population.
There were 1,068 households out of which 35.4% had children under the age of 18 living with them, 55.3% were married couples living together, 8.9% had a female householder with no husband present, and 32.2% were non-families. 26.3% of all households were made up of individuals and 7.1% had someone living alone who was 65 years of age or older. The average household size was 2.46 and the average family size was 3.00.
In the town the population was spread out with 26.4% under the age of 18, 4.7% from 18 to 24, 35.4% from 25 to 44, 24.2% from 45 to 64, and 9.4% who were 65 years of age or older. The median age was 37 years. For every 100 females there were 95.3 males. For every 100 females age 18 and over, there were 92.3 males.
The median income for a household in the town was $78,121, and the median income for a family was $88,671. Males had a median income of $61,442 versus $46,397 for females. The per capita income for the town was $37,463. About 0.4% of families and 2.8% of the population were below the poverty line, including 0.6% of those under age 18 and 1.6% of those age 65 or over.
Interstate 78 and Route 31 both pass through Clinton.