Lewis County's 2026 population is estimated at 3,704, reflecting a -0.32% growth rate over the past year (World Population Review estimate based on U.S. Census Bureau data). Lewis County is the 41st largest county in Idaho. The 2010 population was 3,820 and has grown -3.04% since 2010.
Data after 2023 is projected based on recent change
Overall: 49 years
Female: 48.7 years
Male: 50 years
There are 2,874 adults, (1,043 of whom are seniors) in Lewis County.
Female: 1,832 (49.8%)
Male: 1,850 (50.2%)
The racial composition of Lewis County includes 82.81% White, and smaller percentages for other race, Native American, Black or African American, Asian and multiracial populations.
| Race | Population ↓ | Percentage (of total) |
|---|---|---|
| White | 3,049 | 82.81% |
| Two or more races | 419 | 11.38% |
| Other race | 87 | 2.36% |
| Native American | 48 | 1.3% |
| Black or African American | 42 | 1.14% |
| Asian | 37 | 1% |
Lewis County 's average per capita income is $41,528. Household income levels show a median of $51,615. The poverty rate stands at 15.31%.
| Name | Median ↓ | Mean |
|---|---|---|
| Married Families | $72,266 | - |
| Families | $65,417 | $85,324 |
| Households | $51,615 | $73,126 |
| Non Families | $27,900 | $47,612 |
Average Income
Median Household Income
Poverty Rate
