Rossmoor is an unincorporated community and census-designated place in Monroe Township, Middlesex County, New Jersey, United States. As of the 2020 census, the CDP's population was 2,992, up from 2,666 in 2010. Rossmoor is a gated age-restricted co-op, active adult community. Rossmoor covers 418 acres just off Exit 8A of the New Jersey Turnpike. It has 2,303 residences, encircling a 104-acre championship golf course.