Barnhart is located in Jefferson county Missouri with a geographic area of 5.1 square miles. The total population in Barnhart is 6,676 with 49.0% male and 51.0% female. Children under age 5 represent 9.6% of the population, under age 18 equal 24.7% of the population and over age 65 is 9.1% of the population. The median household income is $86,509, per capita income is $32,636. There are a total of 2,192 housing units with 92.3% owner occupied. Education includes 29.7% of residents that are high school graduates and 26.4% with a bachelor's degree or higher. The average temperature in Barnhart in the summer is 77 degrees, and in the winter 32 degrees.