Polk County Flag

Polk County

State:
Iowa
County Seat:
Des Moines

Polk County's estimated 2026 population is 519,581 with a growth rate of 0.59% in the past year according to the most recent United States census data. Polk County is the largest county in Iowa. The 2010 population was 432,360 and has seen a growth of 20.17% since that time.

519,581
Total Population
908
Population Density (mi²)
1
Population Rank (State)
3K 0.59%
Annual Population Growth

Polk County Population

Demographics

Economics and Income Statistics