Flint Hill is a town in northwestern St. Charles County, Missouri, United States.

[5] The community took its name from Flint Hill, Rappahannock County, Virginia, the native home of a share of the first settlers.

[7] Flint Hill is approximately 2.5 miles north of Wentzville just east of U.S. Route 61 on Missouri Route P. McCoy Creek flows past to the north of the community.

[8] According to the United States Census Bureau, the city has a total area of 2.47 square miles (6.40 km2), all land.

14.0% of all households were made up of individuals, and 4.5% had someone living alone who was 65 years of age or older.

The racial makeup of the city was 97.10% White, 0.53% African American, 0.26% Asian, and 2.11% from two or more races.

19.9% of all households were made up of individuals, and 8.8% had someone living alone who was 65 years of age or older.