Lake County's 2026 population is estimated at 10,952, reflecting a -0.25% growth rate over the past year (World Population Review estimate based on U.S. Census Bureau data). Lake County is the 16th largest county in South Dakota. The 2010 population was 11,278 and has grown -2.89% since 2010.
Data after 2023 is projected based on recent change
Overall: 43.8 years
Female: 45 years
Male: 42.7 years
There are 8,826 adults, (2,666 of whom are seniors) in Lake County.
Female: 5,181 (47.2%)
Male: 5,791 (52.8%)
The racial composition of Lake County includes 90.94% White, and smaller percentages for other race, Native American, Two or more races, Asian, Black or African American, Native Hawaiian or Pacific Islander and multiracial populations.
| Race | Population ↓ | Percentage (of total) |
|---|---|---|
| White | 9,978 | 90.94% |
| Other race | 278 | 2.53% |
| Native American | 276 | 2.52% |
| Two or more races | 260 | 2.37% |
| Asian | 81 | 0.74% |
| Black or African American | 80 | 0.73% |
| Native Hawaiian or Pacific Islander | 19 | 0.17% |
Lake County 's average per capita income is $46,963. Household income levels show a median of $76,808. The poverty rate stands at 8.36%.
| Name | Median ↓ | Mean |
|---|---|---|
| Married Families | $108,938 | - |
| Families | $97,647 | $127,336 |
| Households | $76,808 | $104,754 |
| Non Families | $47,636 | $67,910 |
Average Income
Median Household Income
Poverty Rate