How many people live in Sumner County, KS?
Updated Apr. 6, 2026Refreshed annually
In 2024, there were about 22,300 people living in Sumner County, KS. That makes Sumner County the 25th-most populous county in Kansas. It is home to 0.75% of people living in the state.
22.3K
population of Sumner County, KS (2024)
0.75%
County share of the Kansas population (2024)
About 22,300 people lived in Sumner County, KS in 2024.
Population estimates, 2000–2024
What are Sumner County, KS’s age demographics?
About 4,700 Sumner County residents are aged 65 and older in 2024. That represents 20.8% of its population. For comparison, the age group represents 17.9% of Kansas’s population and 18% in the US overall.
Another 5,300 Sumner County residents, or 23.9% of the population, were children under 18. For comparison, the age group represents 23.5% of Kansas’s population and 21.6% in the US overall.
A lower share of Sumner County, KS's population is aged 25–44 than the US as a whole.
Population estimates by age group, (2024)
What are Sumner County, KS’s racial and ethnic demographics?
Non-Hispanic white residents make up 87.8% of the Sumner County, KS population, higher than the national share of 57.5%. Sumner County, KS also has a larger share of people identifying as non-Hispanic two or more races (2.6%) than the US overall (2.5%).
In contrast, Sumner County’s Hispanic population accounts for 6.5%, below the 20% nationwide, and the non-Hispanic Black or African American population makes up 1.3% 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.
Sumner County, KS has a higher share of a non-Hispanic white population than Kansas as a whole.
Population estimates by race and ethnicity, (2024)
The largest city or town in Sumner County, KS is Wellington with about 7,600 residents in 2024.
Cities and towns in Sumner County, KS ranked by population
Population (2024), includes only portions within county
| City or town | Population | |
|---|---|---|
| 1. | Wellington | 7,561 |
| 2. | Belle Plaine | 1,445 |
| 3. | Oxford | 1,036 |
| 4. | Mulvane (pt.) | 1,007 |
| 5. | Caldwell | 1,000 |
| 6. | Conway Springs (pt.) | 798 |
| 7. | London | 711 |
| 8. | Argonia | 447 |
| 9. | Conway Springs (pt.) | 337 |
| 10. | South Haven | 325 |
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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.
