| Place Name | O'Fallon Township |
| Place Type | Township |
| ZIP Code(s) | 63366 63376 |
| County | Saint Charles County |
| Area Code(s) | 636 |
| Timezone | Central Daylight Time (CDT) |
| Population (2021) | 29,590 |
| Majority Ethnicity | White 90.72% |
| Metro/Micro Stats Area | St. Louis, MO-IL |
| US Congressional District(s) | Missouri 3rd |
| State House Districts | 64,103,104,107 |
| State Senate Districts | 2,23 |
| Race/Ethnicy | Percentage of Population (2021) |
|---|---|
| White | 90.72% |
| African American | 3.29% |
| Hispanic | 0.09% |
| Asian | 2.7% |
| Native American | 0% |
| Hawaiin/Pacific Islander | 3.21% |