Zip Code 51104 — Sioux City, IA

ZIP Code 51104 is associated with Sioux City, IA, in Woodbury County. The listed population estimate is 23,197; estimated density is 1,198.1 people per square mile. Among records with population estimates, it ranks #2 of 20 in Woodbury County and #36 of 969 in IA.
Page generated: 2026-10-08. This is not the source data release date.

📍 View location on OpenStreetMap (42.535180, -96.403890)

Data MetricLocal Statistic
Postal / Zip Code51104
Primary CitySioux City
State / ProvinceIA
CountyWoodbury
Total Population23,197
Population Density1,198.1 people/sq mi
TimezoneAmerica/Chicago

How 51104 Compares

MetricZIP 51104Woodbury County recordsIA records
Population estimate23,19797,439 (sum)3,210,984 (sum)
Population Density1,198.1 /sq mi----
County population rank#2 of 20----
State population rank#36 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 51103Sioux City2.4 mi16,895
ZIP 51105Sioux City2.6 mi10,415
ZIP 51101Sioux City2.9 mi1,031
ZIP 51108Sioux City3.5 mi5,960
ZIP 51109Sioux City5.8 mi3,606

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 →