Edgewater is a borough located along the Hudson River in Bergen County, New Jersey, United States. As of the 2010 United States Census, the borough had a population of 11,513, reflecting an increase of 3,836 (+50.0%) from the 7,677 counted in the 2000 Census, which had in turn increased by 2,676 (+53.5%) from the 5,001 counted in the 1990 Census.

The borough's history has featured the founding of the first colony in Bergen County, contribution to the Revolutionary War, a period as a "sleepy, pastoral little town" with resort hotels in the 19th century, industrialization in the early 20th century, and a transition to a rapidly growing residential community in the late 20th century.

Edgewater was incorporated as a municipality on December 7, 1894, from portions of Ridgefield Township as the Borough of Undercliff, based on the results of a referendum that passed two days earlier. The borough was formed during the "Boroughitis" phenomenon then sweeping through Bergen County, in which 26 boroughs were formed in the county in 1894 alone. The borough's name was changed to Edgewater on November 8, 1899. The borough was named for its location on the Hudson River.