How many people live in Clay County, SD?
Updated Apr. 6, 2026Refreshed annually
In 2024, there were about 15,200 people living in Clay County, SD. That makes Clay County the 14th-most populous county in South Dakota. It is home to 1.6% of people living in the state.
15.2K
population of Clay County, SD (2024)
1.6%
County share of the South Dakota population (2024)
About 15,200 people lived in Clay County, SD in 2024.
Population estimates, 2000–2024
What are Clay County, SD’s age demographics?
About 2,000 Clay County, SD residents are aged 65 and older in 2024. That represents 13% of its population. For comparison, the age group represents 18.9% of South Dakota’s population and 18% in the US overall.
Another 2,600 Clay County residents, or 17.1% of the population, were children under 18. For comparison, the age group represents 24% of South Dakota’s population and 21.6% in the US overall.
A higher share of Clay County, SD's population is aged 18–24 than the US as a whole.
Population estimates by age group, (2024)
What are Clay County, SD’s racial and ethnic demographics?
Non-Hispanic white residents make up 86.2% of the Clay County, SD population, higher than the national share of 57.5%. Clay County, SD also has a larger share of people identifying as non-Hispanic American Indian and Alaska Native (3.5%) than the US overall (0.72%).
In contrast, Clay County’s Hispanic population accounts for 3.5%, below the 20% nationwide, and the non-Hispanic Black or African American population makes up 1.9% of the county, compared with 12.6% nationally.
Racial and ethnic make up differ based on location. These figures reflect how people identified their race alone (not in combination with other races), and separate out Hispanic or Latino ethnicity, following Census reporting standards.
Clay County, SD has a higher share of a non-Hispanic white population than South Dakota as a whole.
Population estimates by race and ethnicity, (2024)
The largest city or town in Clay County, SD is Vermillion with about 11,900 residents in 2024.
Cities and towns in Clay County, SD ranked by population
Population (2024), includes only portions within county
| City or town | Population | |
|---|---|---|
| 1. | Vermillion | 11,877 |
| 2. | Fairview | 636 |
| 3. | Vermillion | 396 |
| 4. | Wakonda | 343 |
| 5. | Glenwood | 225 |
| 6. | Meckling | 216 |
| 7. | Spirit Mound | 209 |
| 8. | Garfield | 199 |
| 9. | Irene (pt.) | 194 |
| 10. | Prairie Center | 192 |
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Methodology
USAFacts standardizes data, in areas such as time and demographics, to make it easier to understand and compare.
The analysis was generated with the help of AI and reviewed by USAFacts for accuracy.
Page sources
USAFacts endeavors to share the most up-to-date information available. We sourced the data on this page directly from government agencies; however, the intervals at which agencies publish updated data vary.
