Johnson County Flag

Johnson County

State:
Iowa
County Seat:
Iowa City

Johnson County's estimated 2026 population is 163,836 with a growth rate of 1.16% in the past year according to the most recent United States census data. Johnson County is the 4th largest county in Iowa. The 2010 population was 131,344 and has seen a growth of 24.74% since that time.

163,836
Total Population
267
Population Density (mi²)
4
Population Rank (State)
1.9K 1.16%
Annual Population Growth

Johnson County Population

Demographics

Economics and Income Statistics