Clay County, South Dakota Population 2026
Updated April 2026 · US Census ACS 2023 5-Year Estimates · 14th-largest in South Dakota
The population of Clay County, South Dakota is 15,133 as of the 2023 American Community Survey, making it the 14th-largest county in South Dakota. The median household income is $58,794, the median home value is $221,800, and the median age is 24.5.
The population of Clay County has grown 10.2% since 2010 (13,830 → 15,245), a +0.70% annualized rate.
15,133
Population
+0.70%
Annual growth
37
People / sq mi
$58,794
Median Income
$221,800
Median Home Value
Clay County covers 412 sq mi of land at 36.7 people per square mile.
About Clay County, SD
Clay County is a county in South Dakota with a population of 15,133. It ranks #14 among counties in South Dakota by population. The median age is 24.5, younger than the national median. The population is 49.5% male and 50.5% female.
The median household income in Clay County is $58,794, below the US median of $74,580. 4.8% of residents live below the federal poverty level. Home values sit at a median of $221,800, with monthly rent averaging $736. The homeownership rate of 51.8% is lower than the national rate of 64.8%.
Educational attainment in Clay County reflects 46.0% of adults 25 and older holding a bachelor's degree or higher, above the national average of 34.3%. Roughly 7.7% of workers primarily work from home, below the national work-from-home rate of 14.2%. The average commute is 17.7 minutes each way.
Clay County Population History (2010-2024)
The county of Clay County had a population of 13,830 in 2010 and 15,245 in 2024, a 10.2% growth over 14 years. The peak was 15,398 in 2023. Average annual growth rate: 0.71%.
15,245
Population (2024)
13,830
Population (2010)
15,398
Peak (2023)
0.71%
Avg Annual Growth
| Year | Population |
|---|---|
| 2010 | 13,830 |
| 2011 | 13,993 |
| 2012 | 14,077 |
| 2013 | 13,914 |
| 2014 | 13,907 |
| 2015 | 13,798 |
| 2016 | 13,980 |
| 2017 | 14,075 |
| 2018 | 13,985 |
| 2019 | 14,096 |
| 2020 | 15,003 |
| 2021 | 15,170 |
| 2022 | 15,277 |
| 2023 | 15,398 |
| 2024 | 15,245 |
Race & Ethnicity
| White | 86.7% |
| Black or African American | 2.0% |
| Asian | 0.0% |
| Hispanic or Latino (any race) | 6.0% |
| Two or More Races | 0.0% |
Age & Sex
24.5
Median Age
50.5%
Female
49.5%
Male
12.2%
Age 65+
Age Distribution
Children (under 15): 14.8% · Seniors (65+): 12.2%
Income & Poverty
| Median household income | $58,794$-13,627 vs state |
| Mean household income | $76,464 |
| Per-capita income | $29,412 |
| Poverty rate | 4.8%-2.6% vs state |
| Unemployment rate | 5.6% |
| Employment-to-population | 61.0% |
Top Industries by Employment
The largest employment sector in Clay County is professional & business services, accounting for 35.6% of workers.
How residents commute
0.3%
Drive alone
10.7%
Carpool
73.5%
Public transit
7.7%
Work from home
17.7 min
Avg commute
Housing
$221,800$-15,000 vs state
Median home value
$736
Median rent
51.8%
Homeownership rate
6,243
Total housing units
89.1%
Occupied
10.9%
Vacant
48.2%
Renter-occupied
Social & access
90.7%
With health insurance
94.5%
With broadband internet
40.9%
Foreign-born
4.6%
Veterans (18+)
11.7%
With a disability
94.4%
Speak language other than English at home
Education
93.9%
High School+
46.0%
Bachelor's+
Largest cities in South Dakota
Other counties in South Dakota
Part of South Dakota
Metro areas in South Dakota
County rankings
Frequently Asked Questions
Clay County, South Dakota has a population of 15,133 according to the US Census Bureau's 2023 American Community Survey 5-year estimates, making it the 14th-largest county in South Dakota. Population density is 37 people per square mile.
The population of Clay County has grown 10.2% since 2010 (13,830 → 15,245), a +0.70% annualized rate.
The median household income in Clay County, South Dakota is $58,794, with mean (average) household income of $76,464 and per-capita income of $29,412. 4.8% of residents live below the federal poverty level.
In Clay County, the largest racial and ethnic groups are White (86.7%), Hispanic or Latino (6.0%), Black or African American (2.0%). Figures are from the US Census Bureau's 2023 ACS 5-year estimates and reflect self-reported responses.
The median age in Clay County, South Dakota is 24.5 years. Residents are 50.5% female and 49.5% male.
The median home value in Clay County is $221,800 and median monthly rent is $736. 51.8% of occupied housing units are owner-occupied. The county has 6,243 total housing units, 10.9% of which are vacant.
The largest employment sector in Clay County, South Dakota is professional, scientific, and management services, employing 35.6% of workers. The unemployment rate is 5.6%.
Sioux Falls is among the largest cities associated with Clay County, South Dakota, with a population of 197,642.
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Full rankings of South Dakota counties
Statewide data for South Dakota
Population, race, income, age, and trends across South Dakota
Data from the American Community Survey (ACS) 5-Year estimates.
Source: U.S. Census Bureau ACS, 2026.