Blanchester is a village in Clinton and Warren counties in the U.S. state of Ohio. The population was 4,243 at the 2010 census. Blanchester is part of the Wilmington, Ohio Micropolitan Statistical Area, which is also included in the Cincinnati-Wilmington-Maysville, OH-KY-IN Combined Statistical Area.
Blanchester was laid out in 1832 by Joseph and John Blancett, and named for them.
Blanchester is located at 39°17′32″N 83°59′9″W (39.292314, -83.985769).
According to the United States Census Bureau, the village has a total area of 4.25 square miles (11.01 km2), of which 4.15 square miles (10.75 km2) is land and 0.10 square miles (0.26 km2) is water. There is no other community named "Blanchester" in the world.
As of the census of 2010, there were 4,243 people, 1,636 households, and 1,113 families living in the village. The population density was 1,022.4 inhabitants per square mile (394.8/km2). There were 1,854 housing units at an average density of 446.7 per square mile (172.5/km2). The racial makeup of the village was 97.8% White, 0.4% African American, 0.3% Native American, 0.3% Asian, and 1.1% from two or more races. Hispanic or Latino of any race were 0.4% of the population.