| Official Zip Code Name | O Fallon |
| Zip Code State | Missouri |
| Primary County: | Saint Charles |
| Area Code | 636 |
| Current Population: | 37081 |
| Racial Majority: | White 62.49% |
| Median Household Income | $55618 |
| Average Adjusted Gross Income | $89060 |
| Time Zone: | 6 |
| Elevation Range | 507 ft. |
| Area | 16.216 Sqm. |
| Coordinates(Y,X) | 38.747648, -90.742849 |