Raritan is a Borough in Somerset County, New Jersey, United States. As of the United States 2010 Census, the borough population was 6,881.
Raritan is located at 40°34′17″N 74°38′15″W / 40.571302°N 74.637405°W / 40.571302; -74.637405 (40.571302, -74.637405).
According to the United States Census Bureau, the borough has a total area of 2.0 square miles (5.3 km2), all of it land. Raritan is in Raritan Valley ( a line of cities in central NJ). Raritan is in the western division of Raritan Valley along with Branchburg and Bridgewater.