Essex Fells is a borough in Essex County, in the U.S. state of New Jersey. As of the 2020 United States census, the borough's population was 2,244, an increase of 131 from the 2010 census count of 2,113, which in turn had reflected a decline of 49 from the 2,162 counted in the 2000 census. Essex Fells was incorporated as a borough by an act of the New Jersey Legislature on March 31, 1902, from portions of Caldwell Township.