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zipcodes.pro — CITY/IA/ALTON

Alton ZIP code, Iowa

The ZIP code for Alton, IA is 51003, and its area code is 712.

USPS city name
1 ZIP code
Population
1,459
Area code
712
State
Iowa

Alton in numbers

About 1,459 people live in Alton, in 592 households. The median household income is $98,036 a year, 31% above the Iowa median of $75,059 (US: $80,734). The median owner-occupied home is valued at $218,900 (5% above the Iowa median), and median gross rent is $813 a month. The median age is 38.1; 24.3% of adults 25 and over hold a bachelor's degree or higher (31.4% across Iowa); the average commute takes 15 minutes.

Population1,459Alton1,459
Households592Alton592
Median age38.1Alton38.1Iowa38.6US 38.9
Median household income$98,036Alton$98,036Iowa$75,059US $80,734
Median home value$218,900Alton$218,900Iowa$208,000US $332,700
Median gross rent$813Alton$813Iowa$972US $1,413
Bachelor's degree or higher24.3%Alton24.3%Iowa31.4%US 35.7%
Mean commute14.7 minAlton14.7 minIowa19.8 minUS 26.4 min
Population density764 / sq miAlton764 / sq mi

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

ZIP codes addressed as Alton

ZIP codes with the USPS city name Alton
ZIP City Type Population Median income Median home
51003 Alton , IA Standard 1,938 $101,250 $232,700

Map of Alton ZIP codes

51003

The ZIP codes of Alton, IA, 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 Alton

The nearest larger towns are Orange City (6,426 people, 2.5 mi), Sioux Center (8,454 people, 10 mi) and Remsen (1,823 people, 12 mi).

Towns near Alton
TownPopulationDistance
Orange City 6,426 2.5 mi
Sioux Center 8,454 10.1 mi
Sheldon 5,474 15.7 mi
Le Mars 10,640 16.5 mi
Rock Valley 4,059 20.5 mi
Hawarden 2,658 23.9 mi
Cherokee 5,154 28.4 mi

More nearby: every ZIP code in Sioux County · Iowa ZIP codes

Cite this page

zipcodes.pro. “Alton, IA ZIP codes.” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/city/ia/alton

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