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zipcodes.pro — ZIP/18631

18631

ZIP 18631 is Mifflinville, Pennsylvania, in Columbia County; area codes 570 and 272; Eastern time.

Type
Standard
Time zone
America/New_York
County
Columbia
Population
1,100
Coordinates
41.0307, -76.3028
☼ Live from 18631 — Mifflinville, PA

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Where 18631 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 18631
  • 🔢 Type 18631 into a pocket calculator and turn it upside down: IEgBI — not quite a word, sorry.
  • ➕ As a number, 18,631 = 31 × 601. Its digits add up to 19, a total 2,454 other ZIP codes share.
  • 💾In binary, the way a computer stores it: 100100011000111
  • 🏠 Its numerical neighbours: 18630 (Meshoppen, PA, 46 mi away) and 18632 (Mildred, PA, 30 mi away).
  • 🔄 Backwards, 18631 becomes 13681 — and that is a real ZIP code: Richville, NY, 239 miles away.
  • 👥 20 other ZIP codes are made of exactly the same digits (11368, 11386, 13618, 13681, 13861, 31816, …). The farthest-flung twin is 83611 in Cascade, ID, 1,955 miles away.
  • 🧭 Farther north than 67% of all ZIP codes, and farther east than 84%.
  • 🎯1,171 miles east of the geographic center of the Lower 48, near Lebanon, Kansas.
  • 🌏 Dig straight through the Earth from 18631 and you would come out at 41.03°S, 103.70°E — 920 miles from Perth, Australia, the nearest big city to that spot.
  • ☀Longest day of the year: 15h 08m of daylight. Shortest: 9h 13m.
  • 📏 At 1.4 square miles of land, 18631 is bigger than 10% of ZIP codes — room for about 1.1 Central Parks.
🌙 The sky over 18631 today
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🌋 Shake report
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Source: USGS.

People and housing

Population1,100This ZIP1,100
Households517This ZIP517
Housing units533This ZIP533
Median age47.0This ZIP47.0Pennsylvania40.9US 38.9
Median household income$46,125This ZIP$46,125Pennsylvania$77,971US $80,734
Median home value$214,100This ZIP$214,100Pennsylvania$254,500US $332,700
Median gross rent$959This ZIP$959Pennsylvania$1,209US $1,413
Bachelor's degree or higher29.6%This ZIP29.6%
Mean commute21.3 minThis ZIP21.3 min
Population density773.6 / sq miThis ZIP773.6 / sq mi

Business and tax activity

Business establishments27This ZIP27
Employees335This ZIP335
Annual payroll$13,435,000This ZIP$13,435,000

Land area

Land area1.42 sq miThis ZIP1.42 sq mi
Water area0.17 sq miThis ZIP0.17 sq mi

Other place names in 18631

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

ZIP codes near 18631

ZIPCityDistance
18603 Berwick, PA 4.6 mi
18635 Nescopeck, PA 5.3 mi
17815 Bloomsburg, PA 6.6 mi
18601 Beach Haven, PA 7.1 mi
18246 Rock Glen, PA 7.6 mi
17859 Orangeville, PA 7.8 mi
17985 Zion Grove, PA 8.4 mi
18241 Nuremberg, PA 9.3 mi
17878 Stillwater, PA 10.1 mi
18249 Sugarloaf, PA 10.2 mi

Find every ZIP code within 10 miles of 18631 →

Questions about this ZIP code

Where is ZIP code 18631?

18631 is in Mifflinville, Pennsylvania, in Columbia County, part of the Bloomsburg-Berwick, PA micropolitan area. Its published point location is 41.0307, -76.3028.

What county is 18631 in?

18631 lies in Columbia County.

What area code is 18631?

Mifflinville uses area codes 570 and 272, from NANPA's telephone records.

What time zone is 18631 in?

18631 uses America/New_York.

How many people live in 18631?

About 1,100 people live in ZIP code 18631, in 517 households, at 773.6 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 18631?

$46,125 a year, against $77,971 across Pennsylvania.

What ZIP codes are near 18631?

The closest are 18603 (4.6 mi), 18635 (5.3 mi), 17815 (6.6 mi), 18601 (7.1 mi) and 18246 (7.6 mi).

Is 18631 a PO Box ZIP code?

18631 is a standard ZIP code. A normal ZIP code with street delivery.

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zipcodes.pro. “18631 ZIP Code — Mifflinville, Pennsylvania (Columbia County).” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/zip/18631

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