Find the last 4 digits (ZIP+4) for an address in 63121

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ZIP Code 63121 – Saint Louis, MO

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

ZIP code63121
CitySaint Louis
StateMissouri
CountySt. Louis County
Population25,008
Time zoneCentral · local time
ZIP typeStandard (has a Census ZCTA area)
Land area6.77 sq mi
Center (lat, long)38.7081, -90.3006

Area codes in this area

314557

These are the area codes that most often serve ZIP 63121 (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

63133 Saint Louis · 1.8 mi63120 Saint Louis · 2.4 mi63140 Saint Louis · 2.5 mi63135 Saint Louis · 3 mi63130 Saint Louis · 3.3 mi63134 Saint Louis · 3.3 mi63136 Saint Louis · 3.3 mi63114 Saint Louis · 3.4 mi

About ZIP 63121

ZIP code 63121 is assigned to Saint Louis, Missouri. It lies in St. Louis County. Its Census area covers about 6.77 square miles of land. The closest neighboring ZIP is 63133 (Saint Louis), about 1.8 miles away.

Every address in 63121 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