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.

Mercer County is a county located in the U.S. state of New Jersey. Its county seat is Trenton, also the state capital, prompting its nickname The Capital County. Mercer County alone constitutes the Trenton–Princeton metropolitan statistical area and is considered part of the New York combined statistical area by the U.S. Census Bureau, but also directly borders the Philadelphia metropolitan area and is included within the Federal Communications Commission's Philadelphia Designated Media Market Area. The county is part of the Central Jersey region of the state.