Hamilton County's 2026 population is estimated at 14,872, reflecting a 0.05% growth rate over the past year (World Population Review estimate based on U.S. Census Bureau data). Hamilton County is the 50th largest county in Iowa. The 2010 population was 15,634 and has grown -4.87% since 2010.
Data after 2023 is projected based on recent change
Overall: 41.7 years
Female: 44 years
Male: 40.1 years
There are 11,339 adults, (3,157 of whom are seniors) in Hamilton County.
Female: 7,220 (48.5%)
Male: 7,666 (51.5%)
The racial composition of Hamilton County includes 86.46% White, and smaller percentages for other race, Asian, Black or African American, Native American, Native Hawaiian or Pacific Islander and multiracial populations.
| Race | Population ↓ | Percentage (of total) |
|---|---|---|
| White | 12,870 | 86.46% |
| Two or more races | 1,117 | 7.5% |
| Other race | 347 | 2.33% |
| Asian | 338 | 2.27% |
| Black or African American | 144 | 0.97% |
| Native American | 49 | 0.33% |
| Native Hawaiian or Pacific Islander | 21 | 0.14% |
Hamilton County 's average per capita income is $52,709. Household income levels show a median of $72,432. The poverty rate stands at 7.4%.
| Name | Median ↓ | Mean |
|---|---|---|
| Married Families | $104,415 | - |
| Families | $91,821 | $112,328 |
| Households | $72,432 | $92,073 |
| Non Families | $45,340 | $56,134 |
Average Income
Median Household Income
Poverty Rate