Marathon County's estimated 2026 population is 139,770 with a growth rate of 0.24% in the past year according to the most recent United States census data. Marathon County is the 10th largest county in Wisconsin. The 2010 population was 134,064 and has seen a growth of 4.26% since that time.
Data after 2023 is projected based on recent change
Overall: 41.3 years
Female: 41.7 years
Male: 40.8 years
There are 107,273 adults, (26,553 of whom are seniors) in Marathon County.
Female: 68,553 (49.5%)
Male: 69,850 (50.5%)
The racial composition of Marathon County includes 86.98% White, 5.67% Asian, and smaller percentages for other race, Black or African American, Native American, Native Hawaiian or Pacific Islander and multiracial populations.
Race | Population | Percentage (of total) |
|---|---|---|
| White | 120,384 | 86.98% |
| Asian | 7,850 | 5.67% |
| Two or more races | 6,769 | 4.89% |
| Other race | 2,319 | 1.68% |
| Black or African American | 800 | 0.58% |
| Native American | 251 | 0.18% |
| Native Hawaiian or Pacific Islander | 30 | 0.02% |
Marathon County's average per capita income is $51,449. Household income levels show a median of $77,884. The poverty rate stands at 8.7%.
Name | Median | Mean |
|---|---|---|
| Married Families | $107,730 | $128,408 |
| Families | $98,320 | $118,904 |
| Households | $77,884 | $97,899 |
| Non Families | $44,553 | $57,552 |
Average Income
Median Household Income
Poverty Rate