Ballwin is a second-ring western suburb of St. Louis, located in St. Louis County, Missouri, United States. The population was to be 30,404 as of the 2010 census. It was named by Money Magazine in 2005 as 64th on the list of the 100 best cities in America. It is the only city in America named Ballwin.
Ballwin is located at 38°35′41″N 90°32′54″W / 38.59472°N 90.54833°W / 38.59472; -90.54833 (38.594820, -90.548420). According to the United States Census Bureau, the city has a total area of 8.9 square miles (23.2 km²), all of it land.
As of the census of 2000, there were 31,283 people, 11,797 households, and 8,942 families residing in the city. The population density was 3,494.6 people per square mile (1,349.5/km²). There were 12,062 housing units at an average density of 1,347.4 per square mile (520.4/km²). The racial makeup of the city was 93.39% White, 1.50% African American, 0.22% Native American, 3.27% Asian, 0.04% Pacific Islander, 0.51% from other races, and 1.07% from two or more races. Hispanic or Latino of any race were 1.86% of the population.