- Augusta
- Defiance
- Foristell
- Lake Saint Louis
- O Fallon
- Portage Des Sioux
- Saint Charles
- Saint Peters
- Wentzville
- West Alton
- Total Population: 310,784
- Male: 49%
- Female: 51%
- Under 10: 14%
- Ages 10 to 19: 14%
- Ages 20 to 29: 12%
- Ages 30 to 39: 13%
- Ages 40 to 49: 15%
- Ages 50 to 59: 14%
- Ages 60 to 69: 9%
- Ages 70 to 79: 5%
- Over 80: 3%