Complete ZIP Code Details
| ZIP Code | 57421 |
| City | Amherst |
| State | South Dakota (SD) |
| County | Marshall |
| Timezone | America/Chicago |
| Coordinates | 45.7504500, -97.9061800 |
| Population | 75 |
| ZIP Type | STANDARD |
| Country | United States |
| ZIP Code | 57421 |
| City | Amherst |
| State | South Dakota (SD) |
| County | Marshall |
| Timezone | America/Chicago |
| Coordinates | 45.7504500, -97.9061800 |
| Population | 75 |
| ZIP Type | STANDARD |
| Country | United States |