{
  "zip": "57278",
  "type": "standard",
  "type_source": "inferred",
  "city": "Willow Lake",
  "other_place_names": [
    "Mayfield Colony"
  ],
  "state": "SD",
  "state_name": "South Dakota",
  "county": {
    "fips": "46025",
    "name": "Clark County",
    "short_name": "Clark"
  },
  "counties": [
    {
      "county_fips": "46025",
      "name": "Clark County",
      "short_name": "Clark",
      "weight": 1,
      "basis": "land_area"
    }
  ],
  "location": {
    "lat": 44.648834,
    "lng": -97.681153,
    "source": "gazetteer_internal_point",
    "timezone": "America/Chicago"
  },
  "is_zcta": true,
  "parent_zcta": null,
  "metro": null,
  "demographics": {
    "population": 1011,
    "households": 255,
    "housing_units": 285,
    "median_age": 24.6,
    "median_household_income": 70208,
    "median_home_value": 220400,
    "median_rent": 808,
    "pct_bachelors_plus": 25.5,
    "mean_commute_min": 19.6,
    "density_per_sqmi": 6.4
  },
  "business": {
    "establishments": 25,
    "employees": 135,
    "annual_payroll_thousands": 7318
  },
  "tax": {
    "irs_returns": 370,
    "irs_agi_thousands": 30473
  },
  "area": {
    "land_sqmi": 157.591,
    "water_sqmi": 1.246
  },
  "nearest_zips": [
    {
      "zip": "57271",
      "miles": 10.3,
      "city": "Vienna",
      "state": "SD"
    },
    {
      "zip": "57221",
      "miles": 12.1,
      "city": "Bryant",
      "state": "SD"
    },
    {
      "zip": "57322",
      "miles": 13.8,
      "city": "Carpenter",
      "state": "SD"
    },
    {
      "zip": "57225",
      "miles": 16.4,
      "city": "Clark",
      "state": "SD"
    },
    {
      "zip": "57233",
      "miles": 16.9,
      "city": "Erwin",
      "state": "SD"
    },
    {
      "zip": "57242",
      "miles": 18.1,
      "city": "Hazel",
      "state": "SD"
    },
    {
      "zip": "57386",
      "miles": 18.4,
      "city": "Yale",
      "state": "SD"
    },
    {
      "zip": "57231",
      "miles": 19.5,
      "city": "De Smet",
      "state": "SD"
    },
    {
      "zip": "57258",
      "miles": 20.2,
      "city": "Raymond",
      "state": "SD"
    },
    {
      "zip": "57353",
      "miles": 20.8,
      "city": "Iroquois",
      "state": "SD"
    }
  ],
  "release": "2026-10-12",
  "attribution": {
    "source": "zipcodes.pro",
    "url": "https://zipcodes.pro/zip/57278",
    "sources_url": "https://zipcodes.pro/sources",
    "license": "Facts derived from US public-domain data (Census, IRS) and GeoNames (CC BY 4.0). Attribution appreciated: zipcodes.pro",
    "note": "A null value means the source did not publish that figure for this ZIP code. It does not mean zero."
  }
}