Columbia, Illinois

Columbia
Downtown Columbia
Motto: 
Good for business, good for life
Location of Columbia in Monroe County, Illinois.
Coordinates: 38°27′52″N 90°14′30″W / 38.46444°N 90.24167°W / 38.46444; -90.24167
CountryUnited States
StateIllinois
CountySt. Clair and Monroe
Founded1859
Area
 • Total
10.38 sq mi (26.88 km2)
 • Land10.32 sq mi (26.74 km2)
 • Water0.054 sq mi (0.14 km2)
Elevation
446 ft (136 m)
Population
 (2020)
 • Total
10,999
 • Density1,065.4/sq mi (411.37/km2)
Time zoneUTC−6 (CST)
 • Summer (DST)UTC−5 (CDT)
ZIP code
62236
Area code618
FIPS code17-15833
GNIS feature ID2393604
Websitewww.columbiaillinois.com

Columbia is a city mainly in Monroe County with a small portion in St. Clair County in the U.S. state of Illinois, about 12 miles (19 km) south of St. Louis, Missouri. The population was 10,999 at the 2020 census.