| Place Name | St. Marys |
| Place Type | City |
| ZIP Code(s) | 45885 |
| GEOID | 3969680 |
| County | Auglaize County |
| Area Code(s) | 419,567 |
| Timezone | Eastern Daylight Time (EDT) |
| Population (2021) | 8,311 |
| Population Growth Rate (2010-19) | 0.78% |
| Majority Ethnicity | White 97.16% |
| Metro/Micro Stats Area | Wapakoneta, OH |
| US Congressional District(s) | Ohio 4th |
| State House Districts | 82,84 |
| State Senate Districts | 1,12 |
| Race/Ethnicy | Percentage of Population (2021) |
|---|---|
| White | 97.16% |
| African American | 0.39% |
| Hispanic | 0% |
| Asian | 0.49% |
| Native American | 0% |
| Hawaiin/Pacific Islander | 1.95% |