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zipcodes.pro — CITY/MO/O-FALLON

O Fallon ZIP codes, Missouri

O Fallon, MO has 2 ZIP codes (63366 and 63368) and area code 636. The largest is 63366.

USPS city name
2 ZIP codes
Overlapping the city
4 more
Population
93,801
Area code
636

Mail addressed to O Fallon uses the ZIP codes above. 4 more ZIP codes cover part of the city but are addressed as somewhere else; they are listed separately below.

O Fallon in numbers

About 93,801 people live in O Fallon, in 35,471 households, the 7th-largest of Missouri's 1,062 census places. The median household income is $110,443 a year, 56% above the Missouri median of $70,702 (US: $80,734). The median owner-occupied home is valued at $326,200 (42% above the Missouri median), and median gross rent is $1,443 a month. The median age is 38.4; 43.3% of adults 25 and over hold a bachelor's degree or higher (32.4% across Missouri); the average commute takes 26 minutes.

Population93,801O Fallon93,801
Households35,471O Fallon35,471
Median age38.4O Fallon38.4Missouri39.0US 38.9
Median household income$110,443O Fallon$110,443Missouri$70,702US $80,734
Median home value$326,200O Fallon$326,200Missouri$230,300US $332,700
Median gross rent$1,443O Fallon$1,443Missouri$1,033US $1,413
Bachelor's degree or higher43.3%O Fallon43.3%Missouri32.4%US 35.7%
Mean commute25.5 minO Fallon25.5 minMissouri23.5 minUS 26.4 min
Population density3,070 / sq miO Fallon3,070 / sq mi

U.S. Census Bureau, American Community Survey 2020–2024 5-year estimates, for the census place O'Fallon city. Survey estimates carry margins of error, wider for small places. Sources and methods.

ZIP codes addressed as O Fallon

ZIP codes with the USPS city name O Fallon
ZIP City Type Population Median income Median home
63366 O Fallon , MO Standard 54,769 $100,621 $304,500
63368 O Fallon , MO Standard 46,966 $124,297 $349,200

Other ZIP codes overlapping O Fallon

These ZIP codes cover part of O Fallon but are addressed as somewhere else.

ZIP codes overlapping O Fallon
ZIP City Type Population Median income Median home
63304 Saint Charles , MO Standard 43,195 $114,442 $351,000
63367 Lake Saint Louis , MO Standard 29,725 $137,648 $409,100
63376 Saint Peters , MO Standard 74,962 $96,393 $275,400
63385 Wentzville , MO Standard 51,330 $112,199 $347,200

Map of O Fallon ZIP codes

6336663368

The ZIP codes of O Fallon, MO, shaded. Outlines are Census ZIP Code Tabulation Areas (2020), which approximate the mail routes; PO-box and single-address codes have no area and are not drawn. Click any area to open its ZIP code.

Towns near O Fallon

The nearest larger towns are St. Louis (288,512 people, 28 mi), Columbia (128,548 people, 87 mi) and Springfield, IL (113,330 people, 90 mi).

Towns near O Fallon
TownPopulationDistance
Dardenne Prairie 13,503 3.0 mi
Lake St. Louis 18,066 3.5 mi
Cottleville 5,937 4.1 mi
St. Paul 3,456 4.6 mi
St. Peters 59,092 6.2 mi
Weldon Spring 5,310 6.4 mi
Wentzville 47,061 8.4 mi
St. Charles 71,508 11.1 mi
Chesterfield 49,574 11.7 mi
Clarkson Valley 2,584 13.0 mi
Maryland Heights 27,880 14.2 mi
Wildwood 35,133 14.6 mi
Ellisville 10,002 15.3 mi
Moscow Mills 3,823 15.5 mi

More nearby: every ZIP code in St. Charles County · Missouri ZIP codes

Cite this page

zipcodes.pro. “O Fallon, MO ZIP codes.” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/city/mo/o-fallon

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