Jefferson County's estimated 2026 population is 35,738 with a growth rate of 1.25% in the past year according to the most recent United States census data. Jefferson County is the 12th largest county in Idaho. The 2010 population was 26,222 and has seen a growth of 36.29% since that time.
Data after 2023 is projected based on recent change
Overall: 32.8 years
Female: 33.2 years
Male: 32.6 years
There are 22,430 adults, (3,954 of whom are seniors) in Jefferson County.
Female: 16,188 (48.8%)
Male: 16,966 (51.2%)
The racial composition of Jefferson County includes 87.53% White, 3.85% other race, and smaller percentages for Native American, Black or African American, Asian, Native Hawaiian or Pacific Islander and multiracial populations.
Race | Population | Percentage (of total) |
|---|---|---|
| White | 29,020 | 87.53% |
| Two or more races | 2,686 | 8.1% |
| Other race | 1,278 | 3.85% |
| Native American | 79 | 0.24% |
| Black or African American | 45 | 0.14% |
| Asian | 42 | 0.13% |
| Native Hawaiian or Pacific Islander | 4 | 0.01% |
Jefferson County's average per capita income is $47,578. Household income levels show a median of $86,679. The poverty rate stands at 9.68%.
Name | Median | Mean |
|---|---|---|
| Married Families | $97,875 | - |
| Families | $92,015 | $108,437 |
| Households | $86,679 | $99,354 |
| Non Families | $32,612 | $46,062 |
Average Income
Median Household Income
Poverty Rate
