ZIP CodesZIP codes in Saint Charles County, Missouri
Saint Charles County, Missouri has 17 ZIP codes in this list, from 63301 to 63386. They cover 13 places, among them Saint Charles, O Fallon, Augusta and Cottleville.
Nothing in this county matches.
| ZIP code | Place | Land area (sq mi) | Map point |
|---|---|---|---|
| 63301 | Saint Charles | 84.3 | 38.801, -90.507 |
| 63302 | Saint Charles | no area | 38.784, -90.481 |
| 63303 | Saint Charles | 19.8 | 38.762, -90.547 |
| 63304 | Saint Charles | 55.1 | 38.738, -90.623 |
| 63332 | Augusta | 56.5 | 38.573, -90.882 |
| 63338 | Cottleville | no area | 38.746, -90.654 |
| 63341 | Defiance | 38.8 | 38.662, -90.830 |
| 63346 | Flinthill | no area | 38.751, -90.537 |
| 63348 | Foristell | 55.8 | 38.763, -90.934 |
| 63365 | New Melle | 0.3 | 38.716, -90.875 |
| 63366 | O Fallon | 69.3 | 38.824, -90.743 |
| 63367 | Lake Saint Louis | 13.0 | 38.794, -90.785 |
| 63368 | O Fallon | 16.2 | 38.751, -90.730 |
| 63373 | Portage Des Sioux | 18.7 | 38.926, -90.386 |
| 63376 | Saint Peters | 40.1 | 38.780, -90.623 |
| 63385 | Wentzville | 66.8 | 38.802, -90.853 |
| 63386 | West Alton | 33.2 | 38.876, -90.238 |
The ZIP code areas of Saint Charles County add up to about 568 square miles of land (1,471 sq km) as the Census Bureau draws them. The largest is 63301 (Saint Charles), with 84.3 square miles.
Places with more than one code here: Saint Charles (4 codes), O Fallon (2 codes).
Using these codes
- In an address, the ZIP code comes last, after the city and the two-letter state: Saint Charles, MO 63301.
- Tap a ZIP code to open it in the look-up, with a copy button for the address line.
- A code can cross a county line, and one town can have several codes. The table shows the main place of each code.
- "No area" means the Census Bureau draws no area for that code. Such codes are usually for post office boxes or a single building.
Places and counties: GeoNames. Areas: U.S. Census Bureau, 2024 ZIP Code Tabulation Areas. Checked in November 2026. This site is not connected with the United States Postal Service; for mailing, confirm the address with USPS.