St. Charles County, MO ZIP codes
There are 17 ZIP codes in St. Charles County, MO, in 13 towns, from 63301 to 63386. The largest are 63376 (Saint Peters), 63366 (O Fallon) and 63301 (Saint Charles).
The county seat is St. Charles.
- ZIP codes
- 17
- Towns
- 13
- County seat
- St. Charles
- County FIPS
29183- State
- Missouri
- Population
- 414,535
- Median household income
- $104,692
- Land area
- 561 sq mi
- Area code
- 636
- Metro area
- St. Louis
St. Charles County ZIP codes by town
- St. Charles (county seat)
- 63301, 63302, 63303, 63304
Each ZIP code is listed under the county most of its land lies in and the town the Postal Service names it for; a ZIP code's own page shows exactly how it is split.
Map of St. Charles County ZIP codes
The ZIP codes of St. Charles County, shaded. Outlines are Census ZIP Code Tabulation Areas (2020), which approximate the mail routes; PO-box and single-address codes have no area and are not drawn. Click any area to open its ZIP code.
St. Charles County in numbers
About 414,535 people live in St. Charles County, in 161,311 households, the 3rd most populous of Missouri's 115 counties. The median household income is $104,692 a year, 48% above the Missouri median of $70,702 (US: $80,734). The median owner-occupied home is valued at $320,800 (39% above the Missouri median), and median gross rent is $1,370 a month. The median age is 39.8; 42.7% of adults 25 and over hold a bachelor's degree or higher (32.4% across Missouri); the average commute takes 25 minutes.
| Population | 414,535 |
|---|---|
| Households | 161,311 |
| Median age | 39.8 |
| Median household income | $104,692 |
| Median home value | $320,800 |
| Median gross rent | $1,370 |
| Bachelor's degree or higher | 42.7% |
| Mean commute | 24.5 min |
| Population density | 740 / sq mi |
U.S. Census Bureau, American Community Survey 2020–2024 5-year estimates. Survey estimates carry margins of error, wider for small places. Sources and methods.
Largest towns in St. Charles County
| Town | ZIP codes | Population |
|---|---|---|
| O Fallon | 2 | 93,801 |
| St. Charles | 4 | 71,508 |
| St. Peters | 1 | 59,092 |
| Wentzville | 1 | 47,061 |
| Lake St. Louis | 1 | 18,066 |
| Cottleville | 1 | 5,937 |
| Defiance | 1 | 3,515 |
| Foristell | 1 | 1,096 |
| West Alton | 1 | 467 |
| New Melle | 1 | 452 |
| Portage Des Sioux | 1 | 340 |
| Augusta | 1 | 285 |
Population of the census place of that name where there is one, otherwise of the ZIP codes the Postal Service addresses by it. A town's ZIP codes can reach past the county line.
Neighbouring counties
Counties that share a ZIP code with St. Charles County.
Not sure you are in St. Charles County? What county am I in? answers from your location, near a county line included.
Every ZIP code in St. Charles County, with figures
| ZIP | City | Type | Population | Median income | Median home |
|---|---|---|---|---|---|
63301 | Saint Charles , MO | Standard | 52,667 | $85,308 | $267,600 |
63302 | Saint Charles , MO | No street area | — | — | — |
63303 | Saint Charles , MO | Standard | 46,089 | $99,138 | $321,100 |
63304 | Saint Charles , MO | Standard | 43,195 | $114,442 | $351,000 |
63332 | Augusta , MO | Standard | 1,651 | $146,146 | $385,400 |
63338 | Cottleville , MO | No street area | — | — | — |
63341 | Defiance , MO | Standard | 3,515 | $170,598 | $606,800 |
63346 | Flinthill , MO | No street area | — | — | — |
63348 | Foristell , MO | Standard | 10,394 | $115,661 | $386,200 |
63365 | New Melle , MO | Standard | 51 | $53,542 | — |
63366 | O Fallon , MO | Standard | 54,769 | $100,621 | $304,500 |
63367 | Lake Saint Louis , MO | Standard | 29,725 | $137,648 | $409,100 |
63368 | O Fallon , MO | Standard | 46,966 | $124,297 | $349,200 |
63373 | Portage Des Sioux , MO | Standard | 690 | $88,750 | $221,300 |
63376 | Saint Peters , MO | Standard | 74,962 | $96,393 | $275,400 |
63385 | Wentzville , MO | Standard | 51,330 | $112,199 | $347,200 |
63386 | West Alton , MO | Standard | 482 | $110,250 | $157,000 |
Cite this page
zipcodes.pro. “St. Charles County ZIP codes.” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/state/mo/county/st-charles
Underlying data is public domain or openly licensed — sources, vintages and licences.