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zipcodes.pro — ZIP/51109

51109

ZIP 51109 is in Sioux City, Iowa, mostly in Plymouth County; area code 712; Central time. Sioux City has 9 ZIP codes in all.

Type
Standard
Time zone
America/Chicago
County
Plymouth +1 more
Metro area
Le Mars, IA
Population
3,606
Coordinates
42.6103, -96.4700
☼ Live from 51109 — Sioux City, IA

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Local time: —

Where 51109 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 51109
  • 🔢 Type 51109 into a pocket calculator and turn it upside down: GOIIS — not quite a word, sorry.
  • ➕ 51109 is a prime number. It cannot be divided by anything except 1 and itself. Its digits add up to 16, a total 1,922 other ZIP codes share.
  • 💾In binary, the way a computer stores it: 1100011110100101
  • 🏠 Its numerical neighbours: 51108 (Sioux City, IA, 7 mi away) and 51111 (Sioux City, IA, 14 mi away).
  • 🔄 Backwards, 51109 becomes 90115, which is not a ZIP code at all.
  • 👥 28 other ZIP codes are made of exactly the same digits (01519, 01915, 01951, 10159, 10519, 10591, …). The farthest-flung twin is 95011 in Campbell, CA, 1,393 miles away.
  • 🧭 Farther north than 80% of all ZIP codes, and farther west than 72%.
  • 🎯221 miles northeast of the geographic center of the Lower 48, near Lebanon, Kansas.
  • 🌏 Dig straight through the Earth from 51109 and you would come out at 42.61°S, 83.53°E — 789 miles from Port-aux-Français, French Southern Territories, the nearest big city to that spot.
  • ☀Longest day of the year: 15h 19m of daylight. Shortest: 9h 03m.
  • 📏 At 17.6 square miles of land, 51109 is bigger than 35% of ZIP codes — room for about 13 Central Parks.
🌙 The sky over 51109 today
  • Working out the sun…
🌋 Shake report
  • Checking the USGS…

Source: USGS.

People and housing

Population3,606This ZIP3,606
Households1,447This ZIP1,447
Housing units1,488This ZIP1,488
Median age39.4This ZIP39.4Iowa38.6US 38.9
Median household income$79,034This ZIP$79,034Iowa$75,059US $80,734
Median home value$130,900This ZIP$130,900Iowa$208,000US $332,700
Median gross rent$627This ZIP$627Iowa$972US $1,413
Bachelor's degree or higher3.4%This ZIP3.4%
Mean commute16.4 minThis ZIP16.4 min
Population density204.8 / sq miThis ZIP204.8 / sq mi

Business and tax activity

Business establishments57This ZIP57
Employees349This ZIP349
Annual payroll$9,468,000This ZIP$9,468,000
Tax returns filed1,440This ZIP1,440
Total adjusted gross income$80,193,000This ZIP$80,193,000

Land area

Land area17.61 sq miThis ZIP17.61 sq mi
Water area0.84 sq miThis ZIP0.84 sq mi

Counties 51109 spans

A ZIP code is a mail route and ignores county lines. Shares are by overlapping land area.

CountyShare of this ZIP
Plymouth County 89.7%
Woodbury County 10.3%

Other place names in 51109

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

ZIP codes near 51109

ZIPCityDistance
57038 Jefferson, SD 5.9 mi
51104 Sioux City, IA 6.2 mi
57049 North Sioux City, SD 6.3 mi
51103 Sioux City, IA 6.3 mi
51108 Sioux City, IA 6.7 mi
51062 Westfield, IA 6.9 mi
51105 Sioux City, IA 8.8 mi
51101 Sioux City, IA 8.9 mi
51038 Merrill, IA 10.1 mi
68776 South Sioux City, NE 10.5 mi

Find every ZIP code within 10 miles of 51109 →

Questions about this ZIP code

Where is ZIP code 51109?

51109 is in Sioux City, Iowa, in Plymouth County, part of the Le Mars, IA micropolitan area. Its published point location is 42.6103, -96.4700.

What county is 51109 in?

51109 spans 2 counties: Plymouth County and Woodbury County. Most of it falls in Plymouth County, measured by overlapping land area — the county holding the most land in a ZIP code is not always the one holding the most residents.

What area code is 51109?

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

What time zone is 51109 in?

51109 uses America/Chicago.

How many people live in 51109?

About 3,606 people live in ZIP code 51109, in 1,447 households, at 204.8 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 51109?

$79,034 a year, against $75,059 across Iowa.

What ZIP codes are near 51109?

The closest are 57038 (5.9 mi), 51104 (6.2 mi), 57049 (6.3 mi), 51103 (6.3 mi) and 51108 (6.7 mi).

Is 51109 a PO Box ZIP code?

51109 is a standard ZIP code. A normal ZIP code with street delivery.

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Cite this page

zipcodes.pro. “51109 ZIP Code — Sioux City, Iowa (Plymouth County).” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/zip/51109

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