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zipcodes.pro — ZIP/51104

51104

ZIP 51104 is in Sioux City, Iowa, in Woodbury County; area code 712; Central time. Sioux City has 9 ZIP codes in all.

Type
Standard
Time zone
America/Chicago
County
Woodbury
Population
23,197
Coordinates
42.5345, -96.4032
☼ Live from 51104 — Sioux City, IA

Weather right now

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NEXRAD radar
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Local time: —

Where 51104 is

Approximate ZIP boundary (Census ZCTA 2020). ZIP codes are mail routes, not areas, so the shape shown is the Census tabulation area that approximates it.

★ Weird and wonderful facts about 51104
  • 🔢 Type 51104 into a pocket calculator and turn it upside down: hOIIS — not quite a word, sorry.
  • ➕ As a number, 51,104 = 2 × 2 × 2 × 2 × 2 × 1597. Its digits add up to 11, a total 714 other ZIP codes share.
  • 💾In binary, the way a computer stores it: 1100011110100000
  • 🏠 Its numerical neighbours: 51103 (Sioux City, IA, 3 mi away) and 51105 (Sioux City, IA, 3 mi away).
  • 🔄 Backwards, 51104 becomes 40115 — and that is a real ZIP code: Custer, KY, 630 miles away.
  • 👥 33 other ZIP codes are made of exactly the same digits (01451, 01541, 05141, 10154, 10451, 10514, …). The farthest-flung twin is 01451 in Harvard, MA, 1,260 miles away.
  • 🧭 Farther north than 79% of all ZIP codes, and farther west than 72%.
  • 🎯219 miles northeast of the geographic center of the Lower 48, near Lebanon, Kansas.
  • 🌏 Dig straight through the Earth from 51104 and you would come out at 42.53°S, 83.60°E — 795 miles from Port-aux-Français, French Southern Territories, the nearest big city to that spot.
  • ☀Longest day of the year: 15h 18m of daylight. Shortest: 9h 03m.
  • 📏 At 7.5 square miles of land, 51104 is bigger than 23% of ZIP codes — room for about 5.7 Central Parks.
🌙 The sky over 51104 today
  • Working out the sun…
🌋 Shake report
  • Checking the USGS…

Source: USGS.

People and housing

Population23,197This ZIP23,197
Households8,729This ZIP8,729
Housing units9,118This ZIP9,118
Median age37.5This ZIP37.5Iowa38.6US 38.9
Median household income$75,362This ZIP$75,362Iowa$75,059US $80,734
Median home value$211,100This ZIP$211,100Iowa$208,000US $332,700
Median gross rent$998This ZIP$998Iowa$972US $1,413
Bachelor's degree or higher28.9%This ZIP28.9%
Mean commute18.5 minThis ZIP18.5 min
Population density3,103.3 / sq miThis ZIP3,103.3 / sq mi

Business and tax activity

Business establishments295This ZIP295
Employees4,147This ZIP4,147
Annual payroll$200,225,000This ZIP$200,225,000
Tax returns filed10,360This ZIP10,360
Total adjusted gross income$717,105,000This ZIP$717,105,000

Land area

Land area7.48 sq miThis ZIP7.48 sq mi
Water area0.00 sq miThis ZIP0.00 sq mi

Other place names in 51104

Census places whose land this ZIP code overlaps. The Postal Service may accept other city names in an address, too.

ZIP codes near 51104

ZIPCityDistance
51103 Sioux City, IA 2.6 mi
51105 Sioux City, IA 2.6 mi
51101 Sioux City, IA 2.9 mi
51108 Sioux City, IA 3.4 mi
57049 North Sioux City, SD 5.5 mi
68776 South Sioux City, NE 5.6 mi
51109 Sioux City, IA 6.2 mi
51106 Sioux City, IA 6.7 mi
51111 Sioux City, IA 8.0 mi
57038 Jefferson, SD 9.3 mi

Find every ZIP code within 10 miles of 51104 →

Questions about this ZIP code

Where is ZIP code 51104?

51104 is in Sioux City, Iowa, in Woodbury County, part of the Sioux City, IA-NE-SD metropolitan area. Its published point location is 42.5345, -96.4032.

What county is 51104 in?

51104 lies in Woodbury County.

What area code is 51104?

Sioux City uses area code 712, from NANPA's telephone records.

What time zone is 51104 in?

51104 uses America/Chicago.

How many people live in 51104?

About 23,197 people live in ZIP code 51104, in 8,729 households, at 3,103.3 people per square mile. These are American Community Survey 5-year estimates for the ZIP Code Tabulation Area, not a headcount.

What is the median household income in 51104?

$75,362 a year, against $75,059 across Iowa.

What ZIP codes are near 51104?

The closest are 51103 (2.6 mi), 51105 (2.6 mi), 51101 (2.9 mi), 51108 (3.4 mi) and 57049 (5.5 mi).

Is 51104 a PO Box ZIP code?

51104 is a standard ZIP code. A normal ZIP code with street delivery.

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Cite this page

zipcodes.pro. “51104 ZIP Code — Sioux City, Iowa (Woodbury County).” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/zip/51104

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