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zipcodes.pro — ZIP/18109

18109

ZIP 18109 is in Allentown, Pennsylvania, mostly in Lehigh County; area codes 484, 610 and 835; Eastern time. Allentown has 8 ZIP codes in all.

Type
Standard
Time zone
America/New_York
County
Lehigh +1 more
Population
18,446
Coordinates
40.6355, -75.4419
☼ Live from 18109 — Allentown, PA

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Where 18109 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 18109
  • 🔢 Type 18109 into a pocket calculator and turn it upside down: GOIBI — not quite a word, sorry.
  • ➕ As a number, 18,109 = 7 × 13 × 199. Its digits add up to 19, a total 2,454 other ZIP codes share.
  • 💾In binary, the way a computer stores it: 100011010111101
  • 🏠 Its numerical neighbours: 18106 (Allentown, PA, 8 mi away) and 18195 (Allentown, PA, 10 mi away).
  • 🔄 Backwards, 18109 becomes 90181, which is not a ZIP code at all.
  • 👥 23 other ZIP codes are made of exactly the same digits (09811, 10918, 10981, 11980, 18091, 18901, …). The farthest-flung twin is 09811 in APO AE, a military post office, 6,437 miles away.
  • 🧭 Farther north than 62% of all ZIP codes, and farther east than 86%.
  • 🎯1,218 miles east of the geographic center of the Lower 48, near Lebanon, Kansas.
  • 🌏 Dig straight through the Earth from 18109 and you would come out at 40.64°S, 104.56°E — 868 miles from Perth, Australia, the nearest big city to that spot.
  • ☀Longest day of the year: 15h 05m of daylight. Shortest: 9h 16m.
  • 📏 At 8.2 square miles of land, 18109 is bigger than 25% of ZIP codes — room for about 6.3 Central Parks.
🌙 The sky over 18109 today
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🌋 Shake report
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Source: USGS.

People and housing

Population18,446This ZIP18,446
Households7,030This ZIP7,030
Housing units7,519This ZIP7,519
Median age36.6This ZIP36.6Pennsylvania40.9US 38.9
Median household income$58,031This ZIP$58,031Pennsylvania$77,971US $80,734
Median home value$198,800This ZIP$198,800Pennsylvania$254,500US $332,700
Median gross rent$1,331This ZIP$1,331Pennsylvania$1,209US $1,413
Bachelor's degree or higher16.0%This ZIP16.0%
Mean commute23.3 minThis ZIP23.3 min
Population density2,236.4 / sq miThis ZIP2,236.4 / sq mi

Business and tax activity

Business establishments802This ZIP802
Employees17,337This ZIP17,337
Annual payroll$1,083,731,000This ZIP$1,083,731,000
Tax returns filed9,670This ZIP9,670
Total adjusted gross income$431,270,000This ZIP$431,270,000

Land area

Land area8.25 sq miThis ZIP8.25 sq mi
Water area0.23 sq miThis ZIP0.23 sq mi

Counties 18109 spans

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

CountyShare of this ZIP
Lehigh County 94.9%
Northampton County 5.1%

Other place names in 18109

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

ZIP codes near 18109

ZIPCityDistance
18032 Catasauqua, PA 2.0 mi
18002 Lehigh Valley, PA 2.2 mi
18018 Bethlehem, PA 2.5 mi
18102 Allentown, PA 2.6 mi
18101 Allentown, PA 2.7 mi
18105 Allentown, PA 3.1 mi
18017 Bethlehem, PA 3.3 mi
18052 Whitehall, PA 3.6 mi
18025 Bethlehem, PA 3.8 mi
18001 Lehigh Valley, PA 4.3 mi

Find every ZIP code within 10 miles of 18109 →

Questions about this ZIP code

Where is ZIP code 18109?

18109 is in Allentown, Pennsylvania, in Lehigh County, part of the Allentown-Bethlehem-Easton, PA-NJ metropolitan area. Its published point location is 40.6355, -75.4419.

What county is 18109 in?

18109 spans 2 counties: Lehigh County and Northampton County. Most of it falls in Lehigh 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 18109?

Allentown uses area codes 484, 610 and 835, from NANPA's telephone records.

What time zone is 18109 in?

18109 uses America/New_York.

How many people live in 18109?

About 18,446 people live in ZIP code 18109, in 7,030 households, at 2,236.4 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 18109?

$58,031 a year, against $77,971 across Pennsylvania.

What ZIP codes are near 18109?

The closest are 18032 (2 mi), 18002 (2.2 mi), 18018 (2.5 mi), 18102 (2.6 mi) and 18101 (2.7 mi).

Is 18109 a PO Box ZIP code?

18109 is a standard ZIP code. A normal ZIP code with street delivery.

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Cite this page

zipcodes.pro. “18109 ZIP Code — Allentown, Pennsylvania (Lehigh County).” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/zip/18109

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