| Place Name | Weldon Spring |
| Place Type | City |
| ZIP Code(s) | 63304 63368 |
| County | Saint Charles County |
| Area Code(s) | 636 |
| Timezone | Central Daylight Time (CDT) |
| Population (2022) | 5,473 |
| Population Growth Rate (2010-19) | -2.15% |
| Majority Ethnicity | White 96.48% |
| Metro/Micro Stats Area | St. Louis, MO-IL |
| US Congressional District(s) | Missouri 2nd |
| State House Districts | 70,102,103 |
| State Senate Districts | 23 |
| Race/Ethnicy | Percentage of Population (2021) |
|---|---|
| White | 96.48% |
| African American | 2.57% |
| Hispanic | 0% |
| Asian | 0.62% |
| Native American | 0% |
| Hawaiin/Pacific Islander | 0.32% |