ZIP code · Mound City · South Dakota · United States
ZIP code 57646 — Mound City
ZIP code 57646 serves Mound City, South Dakota.
- Postal code
- 57646Single source Value from one source, not cross-checked.
- City
- Mound City
- County
- Campbell FIPS 46021
- State
- South Dakota
- Country
- United States
- Coordinates
- 45.6786, -100.0479 — precision precise (locality)
View on OpenStreetMap - Population
- 248 (ZCTA, ACS 5-year)
- Population density
- 2 / sq mi
- Land area
- 128.4 sq mi (332.6 km²) (ZCTA, ACS 5-year)
- Per-capita income
- $33,411
- Median age
- 37.6
- Households
- 106
- Housing units
- 144
- Median home value
- $101,400
- Congressional district
- SD At-large (119th Congress)
- USDA hardiness zone
- 4b (-25 to -20 °F)Planting / growing zone from the 2023 USDA Plant Hardiness Zone Map: average annual extreme minimum temperature, 1991–2020.
- 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.
Tools: compare 57646 with another ZIP · ZIPs within 25 miles · distance from 57646
Map of ZIP code 57646
Climate — monthly normals
Warmest month Jul (avg high 84°F), coldest Jan (avg low 4°F).
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg high °F | 23 | 28 | 41 | 55 | 67 | 78 | 84 | 83 | 74 | 58 | 41 | 28 |
| Avg low °F | 4 | 8 | 19 | 31 | 44 | 55 | 60 | 58 | 48 | 34 | 21 | 10 |
| Precip in | 0.4 | 0.6 | 0.8 | 1.6 | 2.8 | 3.5 | 2.7 | 2.4 | 1.6 | 1.8 | 0.5 | 0.5 |
NOAA 1991–2020 climate normals from the nearest station: SELBY (11.7 mi) · NOAA NCEI
Places in ZIP 57646
- 1 bars & pubs
- 1 post offices
- 3 places of worship
Places mapped inside this ZIP’s ZCTA area in OpenStreetMap. OSM is community-maintained: counts reflect what has been mapped, and completeness varies by area — treat them as at-least figures. © OpenStreetMap contributors (ODbL) · Methodology
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) · U.S. Census Bureau · NOAA NCEI · usda-phzm. Data generated on 2026-08-21. Methodology · Report an error on this page