Twin Rivers is an unincorporated community and census-designated place (CDP) situated within East Windsor Township, in Mercer County, in the U.S. state of New Jersey. As of the 2020 United States census, Twin Rivers' population was 7,787 its highest decennial count ever and an increase of 344 (+4.6%) from the 7,443 recorded at the 2010 census, which in turn reflected an increase of 21 (+0.3%) from the 7,422 counted in the 2000 census. Twin Rivers was the first planned unit development in New Jersey.

East Windsor is a township in Mercer County, in the U.S. state of New Jersey. Located at the cross-roads between the Delaware Valley region to the southwest and the Raritan Valley region to the northeast, the township is an outer-ring suburb of New York City in the New York Metropolitan area, as defined by the United States Census Bureau, but directly borders the Philadelphia metropolitan area and is part of the Federal Communications Commission's Philadelphia Designated Market Area. Since East Windsor is situated at the confluence of several major highways that serve both the major cities of New York City and Philadelphia, and even the local commercial hubs of nearby Freehold, Princeton, and the state capital of Trenton, the community has been a longtime residential, commercial, and industrial hub in the heart of Central New Jersey.