| Place Name | St. Marys |
| Place Type | City |
| ZIP Code(s) | 66536 |
| County | Pottawatomie County |
| Area Code(s) | 785 |
| Timezone | Central Standard Time (CST) |
| Population (2022) | 2,831 |
| Population Growth Rate (2010-19) | 5.02% |
| Majority Ethnicity | White 88.93% |
| Metro/Micro Stats Area | Manhattan, KSTopeka, KS |
| US Congressional District(s) | Kansas 1st |
| State House Districts | 61 |
| State Senate Districts | 18 |
| Race/Ethnicy | Percentage of Population (2021) |
|---|---|
| White | 88.93% |
| African American | 0.78% |
| Hispanic | 0.15% |
| Asian | 4.79% |
| Native American | 0% |
| Hawaiin/Pacific Islander | 5.35% |