Question: what's the zip code for o'fallon missouri
Answer: 03 km ) Elevation 541 ft ( 165 m ) Population ( 2010 ) City 79,329 Estimate ( 2016 ) 86,274 Density 2,700 / sq mi ( 1,000 / km ) Metro 2,810,056 ( US : 19th ) Time zone CST ( UTC - 6 ) Summer ( DST ) CDT ( UTC - 5 ) ZIP code 63366 , 63368 Area code ( s ) 636 FIPS code 29 - 54074 GNIS feature ID 0756460 Website http://www.