US ZIP Code
51003

Alton, IA

Sioux County  ·  Iowa

● Active
👥 1,815 Population ↑ 6% since 2019
💰 $85,909 Median HH Income
▲ 13% above avg ↑ 19% since 2019
🎂 34.7 Median Age ↓ 8% since 2019
🏠 $226,300 Median Home Value
▼ 19% below avg ↑ 49% since 2019
🎓 40.8% College Grads
≈ Avg
📊 1.8% Unemployment
▼ 63% below avg ↓ 35% since 2019
ZIP Code Details
ZIP Code51003
CityAlton
StateIowa (IA)
CountySioux County
Area Code712
Elevation1,343 ft
Latitude42.989594
Longitude-95.985959
TimezoneChicago (DST)
FIPS19167
ZIP TypeStandard
StatusActive
People & Population (ACS 2023)
♂ Male 49.8% (903) Female 50.3% (912) ♀

Race & Ethnicity

White: 87.3%Hispanic: 7.9%Black: 2%Asian: 0.7%Other: 2.2%Race
White87.3%
Hispanic7.9%
Black2.0%
Asian0.7%
Other2.2%

Age Breakdown

Under 5
6%
5–17
19%
18–24
13%
25–44
24%
45–64
22%
65+
7%

Key Indicators

Median Age34.7 yrs ↓ 8% since 2019
Avg Household Size2.56
Below Poverty2.2% ▼ 78% below avg
College Grads40.8% ≈ Avg
Unemployment1.8% ▼ 63% below avg
No HS Diploma3 (0.3%)
HS Graduate381 (35.1%)
Some College81 (7.5%)
Associates177 (16.3%)
Bachelors148 (13.7%)
Graduate Degree294 (27.1%)

Education

No HS: 0.3%HS Grad: 35.1%Some College: 7.5%Associates: 16.3%Bachelors: 13.7%Graduate: 27.1%Edu
No HS0.3%
HS Grad35.1%
Some College7.5%
Associates16.3%
Bachelors13.7%
Graduate27.1%
Housing & Income

Housing Tenure

Owner: 88%Renter: 12%Tenure
Owner88.0%
Renter12.0%

Home Value Distribution

Under $50k
3%
$50k–100k
11%
$100k–150k
12%
$150k–200k
14%
$200k–300k
26%
$300k–500k
31%
Over $500k
3%

Financials

Median HH Income$85,909 ▲ 13% above avg ↑ 19% since 2019
Median Home Value$226,300 ▼ 19% below avg ↑ 49% since 2019
Home/Income Ratio2.6x (nat avg ~3.5x)
Median Rent$750/mo ↓ 2% since 2019
Total Units762
Vacant Units54
Avg HH Size2.56

Income Distribution

Under $25k
6%
$25k–50k
16%
$50k–75k
13%
$75k–100k
21%
$100k–150k
21%
$150k–200k
13%
Over $200k
11%
Employment & Commute

How People Get to Work

Drove Alone
93%
Public Transit
1%
Walked
1%
Work From Home
6%

Commute Time

Under 15 min
55%
15–30 min
40%
30–45 min
3%
Over 45 min
3%
Housing Stock

Year Built

Before 1940
2%
1940s–1950s
12%
1960s–1970s
14%
1980s–1990s
12%
2000+
60%

Summary

Total Units762
Vacant54
Owner Occupied88.0%
Renter Occupied12.0%
Avg HH Size2.56
Frequently Asked Questions
ZIP code 51003 is in Alton, IA, in Sioux County.
ZIP code 51003 is located in Iowa (IA).
ZIP code 51003 is in Sioux County, IA.
ZIP 51003 observes the Chicago timezone. Daylight Saving Time is observed.
The estimated population of ZIP code 51003 is 1,815 people (ACS 2023).
The median household income in ZIP code 51003 is $85,909 (ACS 2023).
The median home value in ZIP 51003 is $226,300 (ACS 2023).
About ZIP Code 51003

ZIP code 51003 is located in Alton, Iowa, within Sioux County. With a population of 1,815, this is a sparsely populated ZIP code with a relatively young community — the median age is 34.7 years. Economically, 51003 is a middle-income ZIP code: the median household income of $85,909 is near the national average.

Real estate in ZIP code 51003 represents an affordable housing market. The median home value of $226,300 is below the national average. Renters can expect to pay around $750 per month in median rent. Homeownership is strong here — 88.0% of occupied units are owner-occupied, suggesting an established, stable residential community. Median home values have increased by 49% since 2019.

The population of 51003 is primarily White (87.33%). Residents are well-educated — 40.8% hold a bachelor's degree or higher, which is near the national average. Poverty affects a relatively small share of residents at 2.2%. Household income has grown by 19% since 2019.

The unemployment rate in 51003 stands at 1.8%, which is well below the national average. As in most parts of the country, driving alone is the dominant commute mode at 86%.

Overall, ZIP code 51003 in Alton, IA is characterized as middle-income, well-educated, a relatively young community, and predominantly owner-occupied. With 1,815 residents, a median household income of $85,909, and a median home value of $226,300, it offers a clear picture of life in this part of Iowa.