Mercer County, Missouri

Mercer County, Missouri
Mercer County Courthouse and downtown Princeton
Location within the U.S. state of Missouri
Coordinates: 40°25′N 93°34′W / 40.42°N 93.57°W / 40.42; -93.57
Country United States
State Missouri
FoundedFebruary 14, 1845
Named afterJohn Francis Mercer
SeatPrinceton
Largest cityPrinceton
Area
 • Total
455 sq mi (1,180 km2)
 • Land454 sq mi (1,180 km2)
 • Water1.3 sq mi (3.4 km2)  0.3%
Population
 (2020)
 • Total
3,538
 • Estimate 
(2024)
3,452
 • Density7.6/sq mi (2.9/km2)
Time zoneUTC−6 (Central)
 • Summer (DST)UTC−5 (CDT)
Congressional district6th

Mercer County is a county located in the northwestern portion of the U.S. state of Missouri. As of the 2020 census, the population was 3,538, making it the second-least populous county in Missouri. Its county seat is Princeton. The county was organized February 14, 1845, and named for General John F. Mercer of the Revolutionary War.