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zipcodes.pro — ZIP/51056

51056

ZIP 51056 is Smithland, Iowa, mostly in Woodbury County; area code 712; Central time.

Type
Standard
Time zone
America/Chicago
County
Woodbury +1 more
Population
346
Coordinates
42.2413, -95.9564
☼ Live from 51056 — Smithland, IA

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Local time: —

Where 51056 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 51056
  • 🔢 Type 51056 into a pocket calculator and turn it upside down: gSOIS — not quite a word, sorry.
  • ➕ As a number, 51,056 = 2 × 2 × 2 × 2 × 3191. Its digits add up to 17, a total 2,133 other ZIP codes share.
  • 💾In binary, the way a computer stores it: 1100011101110000
  • 🏠 Its numerical neighbours: 51055 (Sloan, IA, 16 mi away) and 51058 (Sutherland, IA, 57 mi away).
  • 🔄 Backwards, 51056 becomes 65015, which is not a ZIP code at all.
  • 👥 34 other ZIP codes are made of exactly the same digits (01655, 05156, 05651, 06155, 06515, 15056, …). The farthest-flung twin is 01655 in Worcester, MA, 1,225 miles away.
  • 🧭 Farther north than 77% of all ZIP codes, and farther west than 71%.
  • 🎯216 miles northeast of the geographic center of the Lower 48, near Lebanon, Kansas.
  • 🌏 Dig straight through the Earth from 51056 and you would come out at 42.24°S, 84.04°E — 825 miles from Port-aux-Français, French Southern Territories, the nearest big city to that spot.
  • ☀Longest day of the year: 15h 16m of daylight. Shortest: 9h 05m.
  • 📏 At 33.6 square miles of land, 51056 is bigger than 49% of ZIP codes — room for about 26 Central Parks.
🌙 The sky over 51056 today
  • Working out the sun…
🌋 Shake report
  • Checking the USGS…

Source: USGS.

People and housing

Population346This ZIP346
Households173This ZIP173
Housing units190This ZIP190
Median age54.7This ZIP54.7Iowa38.6US 38.9
Median household income$103,313This ZIP$103,313Iowa$75,059US $80,734
Median home value$157,400This ZIP$157,400Iowa$208,000US $332,700
Median gross rent$658This ZIP$658Iowa$972US $1,413
Bachelor's degree or higher22.2%This ZIP22.2%
Mean commute37.9 minThis ZIP37.9 min
Population density10.3 / sq miThis ZIP10.3 / sq mi

Business and tax activity

Business establishments8This ZIP8
Employees42This ZIP42
Annual payroll$1,870,000This ZIP$1,870,000
Tax returns filed200This ZIP200
Total adjusted gross income$14,723,000This ZIP$14,723,000

Land area

Land area33.59 sq miThis ZIP33.59 sq mi
Water area0.12 sq miThis ZIP0.12 sq mi

Counties 51056 spans

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

CountyShare of this ZIP
Woodbury County 85.3%
Monona County 14.7%

Other place names in 51056

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

ZIP codes near 51056

ZIPCityDistance
51051 Rodney, IA 2.5 mi
51044 Oto, IA 4.9 mi
51026 Hornick, IA 5.8 mi
51015 Climbing Hill, IA 9.3 mi
51004 Anthon, IA 9.8 mi
51010 Castana, IA 10.0 mi
51034 Mapleton, IA 10.1 mi
51019 Danbury, IA 12.3 mi
51063 Whiting, IA 14.1 mi
51039 Moville, IA 15.1 mi

Find every ZIP code within 10 miles of 51056 →

Questions about this ZIP code

Where is ZIP code 51056?

51056 is in Smithland, Iowa, in Woodbury County, part of the Sioux City, IA-NE-SD metropolitan area. Its published point location is 42.2413, -95.9564.

What county is 51056 in?

51056 spans 2 counties: Woodbury County and Monona County. Most of it falls in Woodbury 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 51056?

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

What time zone is 51056 in?

51056 uses America/Chicago.

How many people live in 51056?

About 346 people live in ZIP code 51056, in 173 households, at 10.3 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 51056?

$103,313 a year, against $75,059 across Iowa.

What ZIP codes are near 51056?

The closest are 51051 (2.5 mi), 51044 (4.9 mi), 51026 (5.8 mi), 51015 (9.3 mi) and 51004 (9.8 mi).

Is 51056 a PO Box ZIP code?

51056 is a standard ZIP code. A normal ZIP code with street delivery.

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Cite this page

zipcodes.pro. “51056 ZIP Code — Smithland, Iowa (Woodbury County).” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/zip/51056

Machine-readable version of these facts:

curl https://zipcodes.pro/zip/51056.json

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