Piatt County Flag

Piatt County

State:
Illinois
County Seat:
Monticello

Piatt County's estimated 2025 population is 16,536 with a growth rate of -0.55% in the past year according to the most recent United States census data. Piatt County is the 62nd largest county in Illinois. The 2010 population was 16,710 and has seen a growth of -1.04% since that time.

16,536
Total Population
38
Population Density (mi²)
62
Population Rank (State)
-92 -0.55%
Annual Population Growth

Piatt County Population

Demographics

Economics and Income Statistics

Sources

  1. City and Town Population Totals: 2020-2024
  2. US Census State Population Estimates - Most recent state estimates from the Census Bureau's Population Estimates Program
  3. US Census County Population Estimates - Most recent county estimates from the Census Bureau's Population Estimates Program
  4. American Community Survey (2009 - 2013)
  5. Census QuickFacts
  6. Historical Populations of States and Counties (1790 - 1990)