Clay County Flag

Clay County

State:
Illinois
County Seat:
Louisville

Clay County's estimated 2026 population is 12,741 with a growth rate of -0.41% in the past year according to the most recent United States census data. Clay County is the 80th largest county in Illinois. The 2010 population was 13,822 and has seen a growth of -7.82% since that time.

12,741
Total Population
27
Population Density (mi²)
80
Population Rank (State)
-52 -0.41%
Annual Population Growth

Clay County Population

Demographics

Economics and Income Statistics