ZIP Code 57421 — undefined, SD Demographics & Data

ZIP code 57421 covers SD in Marshall County with a population of about 75.

At a glance, the area shows median age of 16.3 versus a U.S. median of about 38.9.

It sits in telephone area code 605; U.S. House district SD-00; the SIOUX FALLS (MITCHELL) media market.

SD is tagged as a Tribal Nation community context (place names indicate a tribal nation community). Local search often includes tribal government offices, public safety, and Indian Health Service (IHS) / wellness topics alongside standard ZIP demographics.

On socioeconomic markers, US5 shows a poverty rate of 0.0%; unemployment rate near 0.0%; 93.1% of adults with a bachelor’s degree or higher (about 59.4 points above the national share (33.7%)).

Labor and commute patterns include leading industry context around Other services and Education; about 54.2% of workers reporting work-from-home (about 39.0 points above the U.S. share (15.2%)); a mean commute of about 11.0 minutes (U.S. average near 26.8).

Housing tenure and rents show owner-occupancy near 100.0% (about 34.6 points above the national owner-occupancy rate (65.4%)).

FEMA’s National Risk Index rates natural-hazard risk for SD as Very Low (composite score 14.5), which is relatively lower than many U.S. communities. The strongest component scores on US5 are wildfire (76.6) and flood (10.4). These scores are county-linked NRI values published for planning context — all ZIP codes in the same county share the same composite score on US5. Useful when comparing insurance and disaster exposure across areas, not a substitute for a parcel-level flood or fire determination.

Climate normals for SD show little to no average snow and around 24.3 inches of annual precipitation.

IRS migration statistics show a net inflow of about 5 for ZIP 57421 (SD) on US5’s published series — a signal of people/tax filers moving in relative to those leaving. Inflows often track job growth, housing demand, or lifestyle migration; treat the figure as a directional indicator rather than a precise headcount.