Zip Code 51101 — Sioux City, IA

ZIP Code 51101 is associated with Sioux City, IA, in Woodbury County. The listed population estimate is 1,031; estimated density is 330.8 people per square mile. Among records with population estimates, it ranks #11 of 20 in Woodbury County and #459 of 969 in IA.
Page generated: 2026-10-08. This is not the source data release date.

📍 View location on OpenStreetMap (42.494130, -96.393610)

Data MetricLocal Statistic
Postal / Zip Code51101
Primary CitySioux City
State / ProvinceIA
CountyWoodbury
Total Population1,031
Population Density330.8 people/sq mi
TimezoneAmerica/Chicago

How 51101 Compares

MetricZIP 51101Woodbury County recordsIA records
Population estimate1,03197,439 (sum)3,210,984 (sum)
Population Density330.8 /sq mi----
County population rank#11 of 20----
State population rank#459 of 969----

Regional sums combine the population estimates in the listed ZIP records; they are not official county or state population totals.

Explore More ZIP Codes

Nearby ZIP Codes in IA

ZIP CodeCityDistancePopulation estimate
ZIP 51105Sioux City1.7 mi10,415
ZIP 51104Sioux City2.9 mi23,197
ZIP 51103Sioux City3.3 mi16,895
ZIP 51106Sioux City4.3 mi28,592
ZIP 51108Sioux City5.5 mi5,960

Data Sources & Methodology: Geographic coordinates and ZIP Code assignments are derived from underlying geographic and postal datasets. Note that ZIP Codes are USPS postal delivery areas, while Census ZCTAs are statistical approximation areas. Read full methodology →