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Sully County, SD
3 cities and towns and 3 ZIP codes in Sully County, South Dakota.
Population
1,526
Land area
1,007sq mi
People per sq mi
2
ZIP codes
3
Cities and towns in Sully County
Sully County at a glance
- Sully County is 87% less dense than South Dakota as a whole.
- Households here earn a median of $72,578 a year, 3% less than the South Dakota figure of $75,081.
- A typical owner-occupied home is valued at $205,400 (20% below South Dakota) and median rent is $842 a month.
- The biggest population centers are Onida (644), Agar (81) and Cow Creek (69).
Local data for Sully County, SD
Counts from official public data
Housing and community stats
Sully County, SD, American Community Survey 2020-2024
Median household income
$72,578
Poverty rate
6.3%
Median home value
$205,400
Median rent
$842/mo
Homeownership
72.8%
Bachelor's or higher
24.1%
Median age
46.9
Average commute
19.3 min
Largest reported origins and ancestries: German Americans (420), Irish Americans (143), Norwegian Americans (111).
Economy and federal money
Jobs, income, federal spending and pandemic loans
Unemployment rate
1.7%
Aug 2026, 0.0 pts in a year
Average annual pay
$56,436
692 jobs, 2025
Income per person
$85,843
BEA, 2024
Federal spending
$31.9M
FY 2026, $22,093 per person
PPP loans
$45.4M
1,185 loans, 5,561 jobs reported
Campaign donations
$229K
Itemized, 2026 cycle
How people get to work
Sully County, SD, workers 16 and older. American Community Survey 5-year estimates
- Drove alone69.2%
- Carpooled12.2%
- Public transit0.0%
- Walked3.2%
- Bicycle0.0%
- Taxi, ride-hailing, motorcycle or other2.0%
- Worked from home13.4%
Average one-way commute: 19.3 minutes for people who do not work from home.
Environment and hazard risk
Sully County, SD, from FEMA, NOAA and EPA
Natural hazard risk
Very Low
Top: wildfire
Storm events since 1996
477
Most often hail
July high / Jan low
87° / 7°F
21.1 inches of rain a year
Toxic release facilities
1
No Superfund sites
Hazards, floods and storm historyCheck a flood zone4 historic places
Health statistics
Share of adults in Sully County, SD, CDC PLACES estimates
Obesity
34.7%
U.S. 33.3% +1.4 pts
Diabetes
12.5%
U.S. 12.1% about the same
Smoking
13.7%
U.S. 12.8% +0.9 pts
Uninsured (18-64)
7.7%
U.S. 11.1% -3.4 pts
Cities, towns and ZIP codes in Sully County
Population shown
Frequently asked questions
- What is the largest city in Sully County, SD?
- Onida is the largest city or town in Sully County, with about 644 residents.
- How many ZIP codes are in Sully County?
- Sully County includes 3 ZIP Code Tabulation Areas, including 57501, 57520, 57564.
- What is the population of Sully County, SD?
- About 1,526 people live in Sully County, based on American Community Survey 5-year estimates.
- What counties border Sully County?
- Sully County borders Hughes County, Dewey County, Stanley County, Potter County, Hyde County.
Source: U.S. Census Bureau (TIGER/Line boundaries, American Community Survey) · Data as of 12/31/2023