How many people live in Atchison County, MO?
Updated Apr. 6, 2026Refreshed annually
In 2024, there were about 5,100 people living in Atchison County, MO. That makes Atchison County the 108th-most populous county in Missouri. It is home to 0.08% of people living in the state.
5.14K
population of Atchison County, MO (2024)
0.08%
County share of the Missouri population (2024)
About 5,100 people lived in Atchison County, MO in 2024.
Population estimates, 2000–2024
What are Atchison County, MO’s age demographics?
About 1,300 Atchison County, MO residents are aged 65 and older in 2024. That represents 25.2% of its population. For comparison, the age group represents 18.8% of Missouri’s population and 18% in the US overall.
Another 1,000 Atchison County, MO residents, or 20.1% of the population, were children under 18. For comparison, the age group represents 22% of Missouri’s population and 21.6% in the US overall.
A higher share of Atchison County, MO's population is aged 65 or older than the US as a whole.
Population estimates by age group, (2024)
What are Atchison County, MO’s racial and ethnic demographics?
Non-Hispanic white residents make up 94.7% of the Atchison County, MO population, higher than the national share of 57.5%.
In contrast, Atchison County’s Hispanic population accounts for 2.7%, below the 20% nationwide, and the non-Hispanic Black or African American population makes up 0.66% 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.
Atchison County, MO has a higher share of a non-Hispanic white population than Missouri as a whole.
Population estimates by race and ethnicity, (2024)
The largest city or town in Atchison County, MO is Tarkio with about 1,500 residents in 2024.
Cities and towns in Atchison County, MO ranked by population
Population (2024), includes only portions within county
| City or town | Population | |
|---|---|---|
| 1. | Tarkio | 1,470 |
| 2. | Rock Port | 1,238 |
| 3. | Fairfax | 623 |
| 4. | Westboro | 112 |
| 5. | Watson | 56 |
| 6. | Balance of Atchison County | 1,640 |
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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.
