How many people live in Marathon County, WI?
Updated Apr. 6, 2026Refreshed annually
In 2024, there were about 139,100 people living in Marathon County, WI. That makes Marathon County the 10th-most populous county in Wisconsin. It is home to 2.3% of people living in the state.
139K
population of Marathon County, WI (2024)
2.3%
County share of the Wisconsin population (2024)
About 139,100 people lived in Marathon County, WI in 2024.
Population estimates, 2000–2024
What are Marathon County, WI’s age demographics?
About 28,100 Marathon County, WI residents are aged 65 and older in 2024. That represents 20.2% of its population. For comparison, the age group represents 19.6% of Wisconsin’s population and 18% in the US overall.
Another 30,700 Marathon County, WI residents, or 22.1% of the population, were children under 18. For comparison, the age group represents 20.8% of Wisconsin’s population and 21.6% in the US overall.
A higher share of Marathon County, WI's population is aged 65 or older than the US as a whole.
Population estimates by age group, (2024)
What are Marathon County, WI’s racial and ethnic demographics?
Non-Hispanic white residents make up 86.4% of the Marathon County, WI population, higher than the national share of 57.5%. Marathon County, WI also has a larger share of people identifying as non-Hispanic Asian (6.6%) than the US overall (6.5%).
In contrast, Marathon County’s Hispanic population accounts for 3.9%, below the 20% nationwide, and the non-Hispanic Black or African American population makes up 0.99% 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.
Marathon County, WI has a higher share of a non-Hispanic white population than Wisconsin as a whole.
Population estimates by race and ethnicity, (2024)
The largest city or town in Marathon County, WI is Wausau with about 40,300 residents in 2024.
Cities and towns in Marathon County, WI ranked by population
Population (2024), includes only portions within county
| City or town | Population | |
|---|---|---|
| 1. | Wausau | 40,262 |
| 2. | Weston | 15,866 |
| 3. | Kronenwetter | 8,435 |
| 4. | Rib Mountain | 7,275 |
| 5. | Rothschild | 5,629 |
| 6. | Mosinee | 4,531 |
| 7. | Maine | 2,614 |
| 8. | Stettin | 2,569 |
| 9. | Schofield | 2,291 |
| 10. | Mosinee | 2,269 |
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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.
