O'Fallon, Missouri

O'Fallon, Missouri
City
Fort Zumwalt Park
Flag Seal
Motto:  Tradition with Vision
Location in the state of Missouri
Coordinates: 38°45′54″N 90°45′29″W / 38.76500°N 90.75806°W / 38.76500; -90.75806
Country	United States
State	Missouri
County	St. Charles
Metro	Greater St. Louis
First Settled	1856
Incorporated	September 25, 1912
Government [1]
• Type	Mayor-council government
Area [2]
• City	30.51 sq mi (79.01 km2)
• Land	30.50 sq mi (79.00 km2)
• Water	0.00 sq mi (0.01 km2)
Elevation [3]	614 ft (187 m)
Population  (2020)
• City	91,316
• Density	2,993.67/sq mi (1,155.87/km2)
• Metro	2,810,056 (US: 19th)
Time zone	UTC−6 (CST)
• Summer (DST)	UTC−5 (CDT)
ZIP code	63366, 63368
Area code	636
FIPS code	29-54074
GNIS feature ID	2395303[3]
Website	www.ofallon.mo.us

O'Fallon (/oʊˈfælən/ oh-FAL-ən) is a city in St. Charles County, Missouri, United States. It is part of the St. Louis metropolitan statistical area, located along Interstates 64 and 70 between Lake St. Louis and St. Peters. As of the 2020 census, O'Fallon had a population of 91,316, making it the most populous suburb of St. Louis, as well as the most populous municipality in St. Charles County and the 7th most populous in Missouri. O'Fallon's namesake in St. Clair County, Illinois, is also part of the St. Louis region. The two cities are one of the few pairs of same-named municipalities to be part of the same metro area.