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zipcodes.pro — ZIP/51101

51101

ZIP 51101 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
1,031
Coordinates
42.4937, -96.3942
☼ Live from 51101 — Sioux City, IA

Weather right now

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NEXRAD radar
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Local time: —

Where 51101 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 51101
  • 🔢 Type 51101 into a pocket calculator and turn it upside down: IOIIS — not quite a word, sorry.
  • ➕ As a number, 51,101 = 137 × 373. Its digits add up to 8, a total 251 other ZIP codes share.
  • 💾In binary, the way a computer stores it: 1100011110011101
  • 🏠 Its numerical neighbours: 51063 (Whiting, IA, 27 mi away) and 51102 (Sioux City, IA, 9 mi away).
  • 🔄 Backwards, 51101 becomes 10115 — and that is a real ZIP code: New York, NY, 1,160 miles away.
  • 👥 13 other ZIP codes are made of exactly the same digits (01115, 01151, 10115, 10151, 10511, 11051, …). The farthest-flung twin is 01151 in Indian Orchard, MA, 1,216 miles away.
  • 🧭 Farther north than 79% of all ZIP codes, and farther west than 72%.
  • 🎯216 miles northeast of the geographic center of the Lower 48, near Lebanon, Kansas.
  • 🌏 Dig straight through the Earth from 51101 and you would come out at 42.49°S, 83.61°E — 797 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 1.2 square miles of land, 51101 is bigger than 9% of ZIP codes — about 582 football fields.
🌙 The sky over 51101 today
  • Working out the sun…
🌋 Shake report
  • Checking the USGS…

Source: USGS.

People and housing

Population1,031This ZIP1,031
Households640This ZIP640
Housing units788This ZIP788
Median age40.8This ZIP40.8Iowa38.6US 38.9
Median household income$15,300This ZIP$15,300Iowa$75,059US $80,734
Median gross rent$708This ZIP$708Iowa$972US $1,413
Bachelor's degree or higher10.9%This ZIP10.9%
Mean commute10.8 minThis ZIP10.8 min
Population density857.0 / sq miThis ZIP857.0 / sq mi

Business and tax activity

Business establishments413This ZIP413
Employees9,223This ZIP9,223
Annual payroll$534,335,000This ZIP$534,335,000
Tax returns filed490This ZIP490
Total adjusted gross income$24,668,000This ZIP$24,668,000

Land area

Land area1.20 sq miThis ZIP1.20 sq mi
Water area0.02 sq miThis ZIP0.02 sq mi

Other place names in 51101

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

ZIP codes near 51101

ZIPCityDistance
51105 Sioux City, IA 1.7 mi
51104 Sioux City, IA 2.9 mi
51103 Sioux City, IA 3.3 mi
68776 South Sioux City, NE 3.5 mi
51106 Sioux City, IA 4.6 mi
51111 Sioux City, IA 5.2 mi
51108 Sioux City, IA 5.4 mi
57049 North Sioux City, SD 6.2 mi
68731 Dakota City, NE 7.8 mi
51054 Sergeant Bluff, IA 8.4 mi

Find every ZIP code within 10 miles of 51101 →

Questions about this ZIP code

Where is ZIP code 51101?

51101 is in Sioux City, Iowa, in Woodbury County, part of the Sioux City, IA-NE-SD metropolitan area. Its published point location is 42.4937, -96.3942.

What county is 51101 in?

51101 lies in Woodbury County.

What area code is 51101?

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

What time zone is 51101 in?

51101 uses America/Chicago.

How many people live in 51101?

About 1,031 people live in ZIP code 51101, in 640 households, at 857.0 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 51101?

$15,300 a year, against $75,059 across Iowa.

What ZIP codes are near 51101?

The closest are 51105 (1.7 mi), 51104 (2.9 mi), 51103 (3.3 mi), 68776 (3.5 mi) and 51106 (4.6 mi).

Is 51101 a PO Box ZIP code?

51101 is a standard ZIP code. A normal ZIP code with street delivery.

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zipcodes.pro. “51101 ZIP Code — Sioux City, Iowa (Woodbury County).” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/zip/51101

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