Find the last 4 digits (ZIP+4) for an address in 63303

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ZIP Code 63303 – Saint Charles, MO

Saint Charles, Missouri · St. Charles County · Central time

ZIP code63303
CitySaint Charles
StateMissouri
CountySt. Charles County
Population46,089
Time zoneCentral · local time
ZIP typeStandard (has a Census ZCTA area)
Land area19.75 sq mi
Center (lat, long)38.7398, -90.5437

Area codes in this area

636

These are the area codes that most often serve ZIP 63303 (including overlays). The exact area code depends on the phone number — landlines, mobiles and overlays can differ even on the same street.

Map

Nearby ZIP codes

63346 Flinthill · 0.9 mi63146 Saint Louis · 4.3 mi63302 Saint Charles · 4.5 mi63045 Earth City · 4.8 mi63043 Maryland Heights · 4.8 mi63006 Chesterfield · 5.6 mi63376 Saint Peters · 5.6 mi63017 Chesterfield · 5.8 mi

About ZIP 63303

ZIP code 63303 is assigned to Saint Charles, Missouri. It lies in St. Charles County. Its Census area covers about 19.75 square miles of land. The closest neighboring ZIP is 63346 (Flinthill), about 0.9 miles away.

Every address in 63303 also has a 4-digit add-on code (ZIP+4) that points to a smaller delivery area. Use the box above to find it.

Sources: US Census Bureau (ZCTA, county relationship files), GeoNames (CC BY 4.0), NANPA via NumberResearch.org (CC BY 4.0). Map © OpenStreetMap contributors. ZIP areas are approximate. Population: U.S. Census Bureau, ACS 5-year estimates, 2024 (ZCTA). Data sources