| Place Name | Letcher |
| Place Type | Town |
| ZIP Code(s) | 57359 |
| County | Sanborn County |
| Area Code(s) | 605 |
| Timezone | Central Daylight Time (CDT) |
| Population (2022) | 167 |
| Population Growth Rate (2010-19) | -8.09% |
| Majority Ethnicity | White 98.88% |
| US Congressional District(s) | South Dakota At-Large |
| State House Districts | 8 |
| State Senate Districts | 8 |
| Race/Ethnicy | Percentage of Population (2021) |
|---|---|
| White | 98.88% |
| African American | 0% |
| Hispanic | 0% |
| Asian | 1.12% |
| Native American | 0% |
| Hawaiin/Pacific Islander | 0% |