57278 ZIP Code — Willow Lake, SD

Clark County, South Dakota

ZIP code 57278 is located in Willow Lake, South Dakota, within Clark County. It covers approximately 157.59 square miles and serves a population of 972 residents. This is a standard ZIP code in the Central (CT) timezone, served by area code 605.

About ZIP code 57278

The housing stock consists of predominantly single-family detached homes. Most homes were built in the pre-1940, giving the area an established character. Median home value is $170,000. Owner-occupancy is high at 81%, well above the national average.

The gap between median ($60,536) and mean household income suggests income inequality — a small number of higher earners pull the average up. The poverty rate of 6% is below the national average. 37% of households receive Social Security income, suggesting a notable retiree or disability population.

The dominant occupation class is management, business, and professional, with agriculture and mining as the leading industry. The average commute of 17 minutes is near the national average. Remote work is prevalent — 32% of workers work from home.

College attainment at 19% is below the national average, consistent with a trades and production-oriented local economy.

Overall, ZIP code 57278 reflects a community defined by a trades-oriented workforce, high homeownership, a high rate of remote workers, and a significant Social Security-dependent population.

972
population
157.59
sq mi land
Standard
ZIP type
Central (CT)
timezone
57278 ZIP code map
Cities in ZIP code 57278

Below are the cities the US Postal Service accepts for ZIP code 57278. Using any city not on this list may result in mail delivery delays.

City Status
Willow Lake Preferred
Nearby ZIP codes
57221 Bryant (12.6 mi) 57322 Carpenter (12.9 mi) 57225 Clark (18.2 mi) 57353 Iroquois (18.7 mi) 57231 De Smet (20 mi)
Demographics updated 05/2026
Population
Total population 972
Population density 6 / sq mi
State FIPS 46
County FIPS 025
Geography
Land area 157.59 sq mi
Water area 1.25 sq mi
Latitude 44.6311
Longitude -97.7350
Timezone Central (CT)
Area code 605
Total population by age
Gender
Race & ethnicity
Economics updated 05/2026
Household income
Income range This ZIP County avg State avg
Under $50k 30.7% 50.3% 41.7%
$50k – $100k 51.1% 31.8% 33.8%
$100k – $200k 17.1% 14.4% 20.1%
Over $200k 1.1% 3.5% 4.4%

Demographics & statistics

972
Population
6
People per sq mi
25.2
Median age
$60,536
Median household income
$23,895
Per capita income
$170,000
Median home value
$813
Median monthly rent
80.7%
Home ownership
5.8%
Poverty rate
0.0%
Unemployment
245
Housing units
19.0%
Bachelor's or higher

Age distribution

Male Female
61
Under 5
63
42
5–9
43
61
10–14
64
48
15–19
50
25
20–24
26
50
25–34
52
28
35–44
28
35
45–54
36
30
55–59
30
35
60–64
36
28
65–74
29
26
75–84
27
10
85+
10
← Male
Female →

Age summary

GroupCount%
Under 1840942.1%
18 and over56357.9%
65 and over13013.4%
Median age25.2 years

Race & ethnicity

White 85.6%
Hispanic or Latino 5.4%
Other race 4.5%
Two or more races 3.4%
Black or African American 1.1%
GroupCount%
White88085.6%
Hispanic or Latino565.4%
Other race464.5%
Two or more races353.4%
Black or African American111.1%

Household income

Income range This ZIP County avg State avg
Under $50k 30.7% 50.3% 41.7%
$50k – $100k 51.1% 31.8% 33.8%
$100k – $200k 17.1% 14.4% 20.1%
Over $200k 1.1% 3.5% 4.4%
Under $10k 4.5%
$10k–$15k 3.7%
$15k–$25k 3.7%
$25k–$35k 4.9%
$35k–$50k 8.2%
$50k–$75k 32.1%
$75k–$100k 20.2%
$100k–$150k 7.0%
$150k–$200k 11.5%
$200k+ 4.1%
Range% of households
Under $10k4.5%
$10k–$15k3.7%
$15k–$25k3.7%
$25k–$35k4.9%
$35k–$50k8.2%
$50k–$75k32.1%
$75k–$100k20.2%
$100k–$150k7.0%
$150k–$200k11.5%
$200k+4.1%
Median income$60,536

Housing

Home values

Under $50k 7.7%
$50k–$100k 16.8%
$100k–$150k 15.3%
$150k–$200k 20.9%
$200k–$300k 24.5%
$300k–$500k 6.1%
$500k–$1M 5.6%
$1M+ 3.1%

Housing overview

MetricValue
Median home value$170,000
Median rent / month$813
Owner occupied80.7%
Renter occupied19.3%
Vacant16.8%
Single-family detached93.8%
Large apartment buildings0.0%
Mobile homes1.0%
Median rooms6.4
Avg household size (owned)3.52

Year built

Era%
2020 or later0.0%
2010–20195.1%
2000–20099.9%
1990–199911.6%
1980–19894.8%
1970–197913.4%
1960–19699.6%
1950–19596.8%
1940–19493.4%
1939 or earlier35.3%

Bedrooms

Size% of units
No bedroom (studio)1.4%
1 bedroom5.5%
2 bedrooms12.0%
3 bedrooms33.6%
4 bedrooms37.3%
5+ bedrooms10.3%

Vehicles per household

Vehicles% of households
No vehicle1.6%
1 vehicle14.0%
2 vehicles27.6%
3 or more56.8%

Heating fuel

Fuel type%
Utility gas31.3%
Electricity41.2%
Propane / LP gas25.9%
Fuel oil0.4%
Wood0.8%
No fuel used0.4%

Households & families

Household typeCount%
Married-couple family16869.1%
Cohabiting couple52.1%
Male householder, no spouse104.1%
Female householder, no spouse6024.7%
Households with children under 189840.3%
Households with seniors (65+)9037.0%
Average household size3.79

Marital status

StatusMaleFemale
Never married24.7%25.9%
Married64.0%49.6%
Separated0.0%0.0%
Widowed0.0%19.6%
Divorced11.3%4.9%

Education

Less than 9th grade 5.7%
Some HS, no diploma 1.0%
HS graduate 42.9%
Some college, no degree 24.9%
Associate's degree 6.5%
Bachelor's degree 17.3%
Graduate / professional 1.6%
Metric%
HS diploma or higher93.3%
Bachelor's or higher19.0%

School enrollment (ages 3–17)

TypeCount%
Nursery / preschool258.4%
Kindergarten217.1%
Elementary school15451.9%
High school8829.6%
College / grad school93.0%

Employment

Industry of employment

Agriculture & mining 42.9%
Education & healthcare 13.9%
Retail trade 10.2%
Arts, food & hospitality 9.4%
Construction 7.0%
Transportation & utilities 4.3%
Professional & management 4.3%
Wholesale trade 3.8%
Manufacturing 1.6%
Other services 1.6%
Finance & real estate 0.5%
Public administration 0.5%

Occupation

Category%
Management, business & arts46.9%
Service5.6%
Sales & office25.7%
Natural resources & construction18.2%
Production & transportation3.5%

Employment type

Type%
Private sector59.2%
Government9.1%
Self-employed30.8%
Unpaid family workers0.8%

Commute

Method%
Drive alone56.6%
Carpool5.9%
Public transit0.0%
Walk3.8%
Work from home31.9%
Other means1.8%
Avg commute (minutes)16.9

Poverty

All people 5.8%
Under 18 years 1.9%
18 and over 8.3%
Married-couple families 0.6%
Female-led households 0.0%

Income support

Source% of households
Social Security37.0%
Retirement income11.9%
Supplemental Security2.5%
Cash public assistance0.4%
Food stamps / SNAP0.4%

Health indicators

Condition%
Obesity34.7%
High blood pressure33.7%
High cholesterol31.6%
Diabetes10.0%
Heart disease7.8%
Stroke3.6%
Asthma8.9%
Arthritis25.9%
Kidney disease3.3%
Pulmonary disease7.0%
Cancer7.9%
Behavior / access%
Smoking19.0%
Binge drinking18.9%
No physical activity24.6%
Less than 7 hrs sleep27.6%
Depression15.2%
Fair or poor health12.7%
Poor mental health10.6%
Poor physical health9.8%
No health insurance12.5%
Visited doctor (checkup)75.5%
Visited dentist66.6%
Cholesterol screening88.8%
Teeth loss15.5%

Veterans & disability

VeteransCount%
Civilian veterans325.7%
Disability%
Any disability7.4%
Under 185.6%
18–64 years1.8%
65 and over31.5%

Health insurance coverage

Type%
Private insurance70.5%
Public insurance33.3%
No insurance4.6%
Uninsured under 194.0%

Language & origin

Language spoken at home (age 5+)

LanguageCount%
English only84987.3%
Spanish101.2%
Other Indo-European101.2%
Asian & Pacific Islander00.0%
Other languages00.0%

Place of birth & citizenship

OriginCount%
Native born (US)95097.7%
Born in same state95097.7%
Born in different state83986.3%
Foreign born00.0%
Naturalized citizen222.3%
Not a US citizen29.1%

Ancestry

AncestryCount%
Polish20921.5%
English10010.3%
Italian929.5%
AncestryCount%
French272.8%
Arab232.4%
Dutch20.2%

Technology access

Metric% of households
Computer access25.0%
Internet access88.1%

Source: U.S. Census Bureau, American Community Survey 2025 estimates.

Frequently asked questions about ZIP code 57278

What city is ZIP code 57278 in?

ZIP code 57278 is primarily assigned to Willow Lake, South Dakota.

What county is ZIP code 57278 in?

ZIP code 57278 falls within Clark County, South Dakota.

Is ZIP code 57278 family-oriented?

42% of residents in ZIP code 57278 are under 18, reflecting a younger, family-oriented community.

Is ZIP code 57278 mostly owner-occupied?

81% of occupied units in ZIP code 57278 are owner-occupied, well above the national average.

Does ZIP code 57278 have a large retiree population?

37% of households in ZIP code 57278 receive Social Security income, suggesting a significant retiree or disability population.

What is the typical home value in ZIP code 57278?

The median home value in ZIP code 57278 is $170,000.

What timezone is ZIP code 57278 in?

ZIP code 57278 observes the CST timezone.

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