Barnhart is a census-designated place (CDP) in Jefferson County, Missouri, United States. The population was 5,682 at the 2010 census.GeographyBarnhart is located at .According to the United States Census Bureau, the CDP has a total area of 5.25sqmi, of which, 5.09sqmi of it is land and 0.16sqmi is water.Demographics2010 censusAs of the census of 2010, there were 5,682 people, 1,920 households, and 1,576 families residing in the CDP. The population density was 1116.3PD/sqmi. There were 2,003 housing units at an average density of 393.5/sqmi. The racial makeup of the CDP was 97.4% White, 0.5% African American, 0.3% Native American, 0.4% Asian, 0.3% from other races, and 1.1% from two or more races. Hispanic or Latino of any race were 2.1% of the population.There were 1,920 households of which 44.0% had children under the age of 18 living with them, 65.3% were married couples living together, 10.8% had a female householder with no husband present, 6.0% had a male householder with no wife present, and 17.9% were non-families. 12.6% of all households were made up of individuals and 2.7% had someone living alone who was 65 years of age or older. The average household size was 2.93 and the average family size was 3.17.
