McCook County's 2026 population is estimated at 5,695, reflecting a -0.66% growth rate over the past year (World Population Review estimate based on U.S. Census Bureau data). McCook County is the 31st largest county in South Dakota. The 2010 population was 5,609 and has grown 1.53% since 2010.
Data after 2023 is projected based on recent change
Overall: 39.5 years
Female: 39.4 years
Male: 39.6 years
There are 4,114 adults, (1,082 of whom are seniors) in McCook County.
Female: 2,784 (48.4%)
Male: 2,967 (51.6%)
The racial composition of McCook County includes 93.17% White, and smaller percentages for Native American, other race, Black or African American and multiracial populations.
| Race | Population ↓ | Percentage (of total) |
|---|---|---|
| White | 5,358 | 93.17% |
| Two or more races | 221 | 3.84% |
| Native American | 103 | 1.79% |
| Other race | 53 | 0.92% |
| Black or African American | 16 | 0.28% |
McCook County 's average per capita income is $50,830. Household income levels show a median of $83,852. The poverty rate stands at 6.81%.
| Name | Median ↓ | Mean |
|---|---|---|
| Married Families | $105,919 | - |
| Families | $99,615 | $116,894 |
| Households | $83,852 | $101,460 |
| Non Families | $51,513 | $63,942 |
Average Income
Median Household Income
Poverty Rate