Mercer County Flag

Mercer County

State:
New Jersey
County Seat:

Mercer County's estimated 2025 population is 397,980 with a growth rate of 1.49% in the past year according to the most recent United States census data. Mercer County is the 12th largest county in New Jersey. The 2010 population was 367,717 and has seen a growth of 8.23% since that time.

397,980
Total Population
1,777
Population Density (mi²)
12
Population Rank (State)
5.8K 1.49%
Annual Population Growth

Mercer 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)