Founded in 1833, Warren County is one of 114 counties in the state of Missouri. Historically, Warren County was formed from Montgomery County. The city of Warrenton is the county seat. With FIPS code of 219, Warren County has a population of 36,518 and area of 432 square miles (1,119 km2).
List of all cities in Warren County, MO alphabetically
| City/Town | Postal Code | Area Code |
| Dutzow, MO | 63342 | 636 |
| Elkhorn, MO | 63383 | 636 |
| Innsbrook, MO | 63390 | 636 |
| Lake Sherwood, MO | 63357 | 636 |
| Marthasville, MO | 63357 | 636 |
| Pendleton, MO | 63383 | 636 |
| Treloar, MO | 63378 | 636 |
| Truesdale, MO | 63383 | 636 |
| Warrenton, MO | 63383 | 636 |
| Wright City, MO | 63390 | 636 |