Prior to 1916, the area was known as Dundee Lake, a section of Saddle River Township. Residents of the Dundee Lake area voted on April 18, 1916, to secede from Saddle River Township to form the Borough of East Paterson. In 1917, residents of the Rosemont section of Saddle River Township voted to be annexed to East Paterson. In November 1972, residents voted to change the name of the Borough to Elmwood Park. The new name became official on January 1, 1973.
As of the census of 2000, there were 18,925 people, 7,089 households, and 5,075 families residing in the borough. The population density was 7,129.8 people per square mile (2,757.4/km). There were 7,242 housing units at an average density of 2,728.3/sq mi (1,055.2/km). The racial makeup of the borough was 82.53% White, 2.16% African American, 0.11% Native American, 7.80% Asian, 0.01% Pacific Islander, 4.44% from other races, and 2.94% from two or more races. Hispanic or Latino of any race were 13.39% of the population.
Elmwood Park is a culturally diverse community. In the mid 2000s Elmwood Park has seen a huge increase in the Polish population.
There were 7,089 households out of which 29.5% had children under the age of 18 living with them, 55.4% were married couples living together, 11.8% had a female householder with no husband present, and 28.4% were non-families. 23.2% of all households were made up of individuals and 12.3% had someone living alone who was 65 years of age or older. The average household size was 2.66 and the average family size was 3.17.
In the borough the population was spread out with 20.9% under the age of 18, 8.0% from 18 to 24, 31.4% from 25 to 44, 23.3% from 45 to 64, and 16.5% who were 65 years of age or older. The median age was 38 years. For every 100 females there were 91.5 males. For every 100 females age 18 and over, there were 88.6 males.
The median income for a household in the borough was $52,319, and the median income for a family was $59,131. Males had a median income of $40,684 versus $39,535 for females. The per capita income for the borough was $28,588. About 4.7% of families and 2.4% of the population were below the poverty line, including 4.7% of those under age 18 and 5.3% of those age 65 or over.
Elmwood Park is served by New Jersey Transit buses 160 and 161 to the Port Authority Bus Terminal in Midtown Manhattan, with local service on the 702, 712, 758 and 770 routes. New Jersey Transit's Bergen County Line also travels through Elmwood Park, but does not have a station stop in the town.
Route 4, Interstate 80, U.S. Route 46, and the Garden State Parkway serve Elmwood Park.
The Passaic-Bergen Rail Line is a planned rail system that will have a stop in Elmwood Park.