ZIP code · Alpena · South Dakota · United States
ZIP code 57312 — Alpena
ZIP code 57312 serves Alpena, South Dakota.
- Postal code
- 57312Single source Value from one source, not cross-checked.
- City
- Alpena
- County
- Jerauld
- State
- South Dakota
- Country
- United States
- Coordinates
- 44.1709, -98.3962 — precision precise (locality)
View on OpenStreetMap - Population
- 619 (ZCTA, ACS 5-year)
- Median household income
- $83,750
- Median age
- 40.8
- Time zone
- America/Chicago (UTC−6 / UTC−5 DST)
- Area code
- 605Telephone area codes serving this ZIP (NANPA central-office assignments). A ZIP and an area code are different boundaries; at a border both codes may apply.
Nearby localities
About this page
US ZIP codes have five digits. They are postal routing areas, not administrative boundaries: a ZIP can span more than one city or county, and the city shown is the primary USPS name for that code.
GeoNames · U.S. Census Bureau (ACS). Data generated on 2026-08-21. Methodology · Report an error on this page