Find the last 4 digits (ZIP+4) for an address in 51003

ZIP 51003, Alton, IA is filled in. Just type the street address.

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ZIP Code 51003 – Alton, IA

Alton, Iowa · Sioux County · Central time

ZIP code51003
CityAlton
StateIowa
CountySioux County
Population1,938
Time zoneCentral · local time
ZIP typeStandard (has a Census ZCTA area)
Land area54.35 sq mi
Center (lat, long)42.9896, -95.9860

Area codes in this area

712

These are the area codes that most often serve ZIP 51003 (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

51041 Orange City · 5.2 mi51022 Granville · 7 mi51238 Hospers · 7.5 mi51036 Maurice · 10.4 mi51045 Oyens · 12.2 mi51250 Sioux Center · 13.1 mi51050 Remsen · 13.2 mi51234 Boyden · 14.1 mi

About ZIP 51003

ZIP code 51003 is assigned to Alton, Iowa. It lies in Sioux County. Its Census area covers about 54.35 square miles of land. The closest neighboring ZIP is 51041 (Orange City), about 5.2 miles away.

Every address in 51003 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