ZIP Code 63366

63366 is one of Missouri's ZIP codes, delivering to addresses in O Fallon, St. Charles County.

City: O Fallon
County: St. Charles County
State: Missouri
Prefix: 633xx

Where this code sits

63366 is part of the 633xx range, the group of codes handled by one mail processing centre. O Fallon is served by 2 ZIP codes in total; the full list, with the county each falls in, is on the O Fallon page.

O Fallon Missouri ZIP codes →

Area codes over the same ground

Postal and telephone geography are drawn separately, so these codes cover the area 63366 delivers to without sharing its boundary.

636 Area code 636

ZIP codes nearest 63366

The ZIP codes whose reference points sit closest to 63366.
ZIP code	Distance	Delivers to
ZIP code 63367	3.1 mi	Lake Saint Louis, MO
ZIP code 63368	5.1 mi	O Fallon, MO
ZIP code 63385	6.1 mi	Wentzville, MO
ZIP code 63376	7.1 mi	Saint Peters, MO
ZIP code 63338	7.2 mi	Cottleville, MO
ZIP code 63369	7.9 mi	Old Monroe, MO
ZIP code 63304	8.8 mi	Saint Charles, MO
ZIP code 63365	10 mi	New Melle, MO

Straight-line distance between place reference points, not driving distance. Where a place has no Census Gazetteer point, its postal centroid is used instead.

Each point is the reference point for 63366, plotted from its record coordinates.

Reference points and footprint
Not an official NANPA boundary
Not a USPS delivery area

Scope ZIP code 63366. Source GeoNames US postal codes (2026-07 postal dump) and Census 2024 county Gazetteer (2024 Gazetteer). Updated 15 July 2026. A ZIP code is a set of delivery routes, not an area; the point shown is a record coordinate, not a centre.