ZIP Code 51231

ZIP code 51231 is classified by USPS as a standard delivery area and covers roughly 72.3 square miles in Archer, O'Brien County, Iowa. The area is home to 282 residents, producing a population density of 4 people per square mile, and falls within the Chicago time zone. These USPS and Census boundary values drive every downstream statistic on this page, including the benchmarks that compare 51231 against Iowa and the nation.

On the economic side, the median household income for ZIP 51231 sits at $108,058 (41% above the Iowa average), while per-capita income is $22,575. The poverty rate stands at 29.7% and the unemployment rate at 0.0%. On housing, the median home value is $189,500 (8% above the state average) with median rent at — per month, and 94.3% of occupied units are owner-occupied, a direct signal of whether 51231 behaves more like a homeowner neighborhood or a renter-heavy ZIP.

Education and household profile round out the picture: 33.5% of adults hold a bachelor's degree or higher, the median age is 15.1, and the average commute is —. We also surface 5 nearby ZIP codes within roughly 10 miles and 6 additional ZIPs sharing O'Brien County, so you can benchmark 51231 against its immediate geography rather than a national average alone. Every figure is sourced from the U.S. Census Bureau American Community Survey 5-Year Estimates, HUD Fair Market Rents, and FHFA Home Price Index data, no estimates, no proprietary scoring. Verify with HUD →