| Place Name | South Dewey |
| Place Type | Unincorporated Territory |
| ZIP Code(s) | 57532 57625 57652 57656 57658 |
| County | Dewey County |
| Area Code(s) | 605 |
| Timezone | (UTC) |
| Population (2021) | 980 |
| Majority Ethnicity | Native American 0% |
| US Congressional District(s) | South Dakota At-Large |
| State House Districts | 28A |
| State Senate Districts | 28 |
| Race/Ethnicy | Percentage of Population (2021) |
|---|---|
| White | 11.13% |
| African American | 0% |
| Hispanic | 86.7% |
| Asian | 0% |
| Native American | 0% |
| Hawaiin/Pacific Islander | 2.16% |