| Place Name | East Custer |
| Place Type | Unincorporated Territory |
| County | Custer County |
| Area Code(s) | 605 |
| Timezone | Mountain Daylight Time (MDT) |
| Population (2021) | 1,272 |
| Majority Ethnicity | White 94.67% |
| US Congressional District(s) | South Dakota At-Large |
| State House Districts | 30 |
| State Senate Districts | 30 |
| Race/Ethnicy | Percentage of Population (2021) |
|---|---|
| White | 94.67% |
| African American | 0% |
| Hispanic | 3.66% |
| Asian | 0.08% |
| Native American | 0% |
| Hawaiin/Pacific Islander | 1.59% |