Greater St. Louis

Combined statistical area in the United StatesGreater St. LouisCombined statistical areaSt. Louis, MO–IL metropolitan statistical areaA NASA image of the Greater St. Louis area at night in December 2013Interactive map of St. Louis–St. Charles–Farmington, MO–IL CSA St. Louis, MO–IL MSA City of St. Louis Greater St. Louis (Missouri) Metro East (Illinois) Other statistical areas in the St. Louis CSA Farmington, MO µSA Centralia, IL µSA Country United StatesState Missouri IllinoisLargest city St. LouisOther cities - O'Fallon, MO - St. Charles, MO - St. Peters, MO - Florissant, MO - Chesterfield, MO - Belleville, IL - O'Fallon, IL - Granite City, IL - Edwardsville, IL - Alton, IL - East St. Louis, IL - Fenton, MO Area • Total8,458 sq mi (21,910 km2) • Land8,261 sq mi (21,400 km2) • Water197 sq mi (510 km2) 2.3%Elevation466–1,280 ft (142–390 m)Population (2020) • Metro density339.8/sq mi (131.2/km2) • MSA2,805,473 (20th) • CSA2,909,003 (20th) MSA/CSA = 2020GDP • MSA$209.9 billion (2022)Time zoneUTC−6 (CST) • Summer (DST)UTC−5 (CDT)Area codes217, 235, 314, 447, 557, 573, 618, 636, 730 Greater St. Louis is the 23rd-largest metropolitan statistical area (