Buchanan County's 2026 population is estimated at 20,749, reflecting a 0.04% growth rate over the past year (World Population Review estimate based on U.S. Census Bureau data). Buchanan County is the 31st largest county in Iowa. The 2010 population was 20,975 and has grown -1.08% since 2010.
Data after 2023 is projected based on recent change
Overall: 40.3 years
Female: 41.5 years
Male: 39 years
There are 15,443 adults, (3,855 of whom are seniors) in Buchanan County.
Female: 10,258 (49.6%)
Male: 10,436 (50.4%)
The racial composition of Buchanan County includes 95.98% White, and smaller percentages for Two or more races, Black or African American, other race, Native American, Asian, Native Hawaiian or Pacific Islander and multiracial populations.
| Race | Population ↓ | Percentage (of total) |
|---|---|---|
| White | 19,862 | 95.98% |
| Two or more races | 517 | 2.5% |
| Black or African American | 124 | 0.6% |
| Other race | 80 | 0.39% |
| Native American | 58 | 0.28% |
| Asian | 40 | 0.19% |
| Native Hawaiian or Pacific Islander | 13 | 0.06% |
Buchanan County 's average per capita income is $48,602. Household income levels show a median of $78,236. The poverty rate stands at 8.6%.
| Name | Median ↓ | Mean |
|---|---|---|
| Married Families | $106,377 | - |
| Families | $94,220 | $104,751 |
| Households | $78,236 | $89,957 |
| Non Families | $40,221 | $53,023 |
Average Income
Median Household Income
Poverty Rate