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zipcodes.pro — ZIP/83321

83321

ZIP 83321 is Castleford, Idaho, in Twin Falls County; area codes 208 and 986; Mountain time.

Type
Standard
Time zone
America/Boise
County
Twin Falls
Metro area
Twin Falls, ID
Population
482
Coordinates
42.3456, -114.8474
☼ Live from 83321 — Castleford, ID

Weather right now

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Local time: —

Where 83321 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 83321
  • 🔢 Type 83321 into a pocket calculator and turn it upside down: IZEEB — not quite a word, sorry.
  • ➕ As a number, 83,321 = 7 × 11903. Its digits add up to 17, a total 2,133 other ZIP codes share.
  • 💾In binary, the way a computer stores it: 10100010101111001
  • 🏠 Its numerical neighbours: 83320 (Carey, ID, 88 mi away) and 83322 (Corral, ID, 67 mi away).
  • 🔄 Backwards, 83321 becomes 12338, which is not a ZIP code at all.
  • 👥 30 other ZIP codes are made of exactly the same digits (12833, 13328, 13832, 18323, 18332, 23138, …). The farthest-flung twin is 33128 in Miami, FL, 2,267 miles away.
  • 🧭 Farther north than 78% of all ZIP codes, and farther west than 88%.
  • 🎯863 miles west of the geographic center of the Lower 48, near Lebanon, Kansas.
  • 🌏 Dig straight through the Earth from 83321 and you would come out at 42.35°S, 65.15°E — 542 miles from Port-aux-Français, French Southern Territories, the nearest big city to that spot.
  • ☀Longest day of the year: 15h 17m of daylight. Shortest: 9h 04m.
  • 📏 At 181.2 square miles of land, 83321 is bigger than 89% of ZIP codes — room for about 138 Central Parks.
🌙 The sky over 83321 today
  • Working out the sun…
🌋 Shake report
  • Checking the USGS…

Source: USGS.

People and housing

Population482This ZIP482
Households210This ZIP210
Housing units231This ZIP231
Median age46.8This ZIP46.8Idaho37.3US 38.9
Median household income$60,000This ZIP$60,000Idaho$77,800US $80,734
Median gross rent$925This ZIP$925Idaho$1,238US $1,413
Bachelor's degree or higher24.3%This ZIP24.3%
Mean commute21.4 minThis ZIP21.4 min
Population density2.7 / sq miThis ZIP2.7 / sq mi

Business and tax activity

Business establishments11This ZIP11
Employees61This ZIP61
Annual payroll$2,462,000This ZIP$2,462,000
Tax returns filed230This ZIP230
Total adjusted gross income$11,431,000This ZIP$11,431,000

Land area

Land area181.18 sq miThis ZIP181.18 sq mi
Water area0.14 sq miThis ZIP0.14 sq mi

Other place names in 83321

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

ZIP codes near 83321

ZIPCityDistance
83301 Twin Falls, ID 16.9 mi
83316 Buhl, ID 19.4 mi
83328 Filer, ID 19.5 mi
83302 Rogerson, ID 20.3 mi
83303 Twin Falls, ID 24.8 mi
83341 Kimberly, ID 24.9 mi
83334 Hansen, ID 28.8 mi
83355 Wendell, ID 29.2 mi
89825 Jackpot, NV 31.3 mi
83332 Hagerman, ID 31.5 mi

Find every ZIP code within 10 miles of 83321 →

Questions about this ZIP code

Where is ZIP code 83321?

83321 is in Castleford, Idaho, in Twin Falls County, part of the Twin Falls, ID metropolitan area. Its published point location is 42.3456, -114.8474.

What county is 83321 in?

83321 lies in Twin Falls County.

What area code is 83321?

Castleford uses area codes 208 and 986, from NANPA's telephone records.

What time zone is 83321 in?

83321 uses America/Boise.

How many people live in 83321?

About 482 people live in ZIP code 83321, in 210 households, at 2.7 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 83321?

$60,000 a year, against $77,800 across Idaho.

What ZIP codes are near 83321?

The closest are 83301 (16.9 mi), 83316 (19.4 mi), 83328 (19.5 mi), 83302 (20.3 mi) and 83303 (24.8 mi).

Is 83321 a PO Box ZIP code?

83321 is a standard ZIP code. A normal ZIP code with street delivery.

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Cite this page

zipcodes.pro. “83321 ZIP Code — Castleford, Idaho (Twin Falls County).” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/zip/83321

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