Hammonton was settled in 1812 and incorporated as a town by an Act of the New Jersey Legislature on March 5, 1866, from portions of Hamilton Township and Mullica Township.
As of the census of 2000, there were 12,604 people, 4,619 households, and 3,270 families residing in the town. The population density was 305.5 people per square mile (117.9/km). There were 4,843 housing units at an average density of 117.4/sq mi (45.3/km). The racial makeup of the town was 87.85% White, 1.74% African American, 0.14% Native American, 1.14% Asian, 0.02% Pacific Islander, 7.83% from other races, and 1.27% from two or more races. Hispanic or Latino of any race were 14.88% of the population.
As of the 2000 census, 45.9% of town residents were of Italian ancestry, the second-highest percentage of any municipality in the United States (behind Johnston, Rhode Island, at 46.7%), and highest in New Jersey, among all places with more than 1,000 residents identifying their ancestry. News reports have said Hammonton leads the nation in Italian-Americans per capita.
There were 4,619 households out of which 30.2% had children under the age of 18 living with them, 54.6% were married couples living together, 11.2% had a female householder with no husband present, and 29.2% were non-families. 23.9% of all households were made up of individuals and 12.5% had someone living alone who was 65 years of age or older. The average household size was 2.65 and the average family size was 3.14.
In the town the population was spread out with 22.8% under the age of 18, 7.9% from 18 to 24, 29.2% from 25 to 44, 22.1% from 45 to 64, and 18.0% who were 65 years of age or older. The median age was 39 years. For every 100 females there were 93.9 males. For every 100 females age 18 and over, there were 92.7 males.
The median income for a household in the town was $43,137, and the median income for a family was $52,205. Males had a median income of $36,219 versus $27,900 for females. The per capita income for the town was $19,889. About 5.7% of families and 9.1% of the population were below the poverty line, including 9.0% of those under age 18 and 10.8% of those age 65 or over.
Atlantic City Expressway, U.S. Route 30, U.S. Route 206 and Route 54 all pass through Hammonton, as do County Route 536, County Route 542, County Route 559 and County Route 561.
The Hammonton station on the Atlantic City Line of New Jersey Transit, provides passenger rail service to the Atlantic City Rail Terminal in Atlantic City, 30th Street Station in Philadelphia and intermediate points.
Hammonton Municipal Airport is located 3 miles (5 km) northeast of the central business district.