Saint Charles County Missouri is covered by a total of 18 ZIP Codes. There are 2 ZIP Codes in Saint Charles County that extend into adjacent counties (Lincoln County, and Warren County). Of the ZIP codes within or partially within Saint Charles County there are 14 Standard ZIP Codes and 4 PO Box ZIP Codes.
Click on the ZIP Codes in the interactive map to view more information. The map control in the upper right corner can be used to toggle map layers on and off. The red outline is the border of Saint Charles County and can be turned on and off. Each type of postal code can also be turned on and off.
| ZIP Code | ZIP Code City/Town | ZIP Code Type | |||
|---|---|---|---|---|---|
| Saint Charles | Standard | |||
| Saint Charles | PO Box | |||
| Saint Charles | Standard | |||
| Saint Charles | Standard | |||
| Augusta | Standard | |||
| Cottleville | PO Box | |||
| Defiance | Standard | |||
| Flinthill | PO Box | |||
| Foristell | Standard | |||
| Marthasville | Standard | |||
| New Melle | PO Box | |||
| O'Fallon | Standard | |||
| Lake Saint Louis | Standard | |||
| O'Fallon | Standard | |||
| Portage Des Sioux | Standard | |||
| Saint Peters | Standard | |||
| Wentzville | Standard | |||
| West Alton | Standard |