Polk County Flag

Polk County

State:
Iowa
County Seat:
Des Moines

Polk County's estimated 2026 population is 533,581 with a growth rate of 1.66% 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 23.41% since that time.

533,581
Total Population
933
Population Density (mi²)
1
Population Rank (State)
8.7K 1.66%
Annual Population Growth

Polk County Population

Demographics

Economics and Income Statistics