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zipcodes.pro — ZIP/02139

02139

ZIP 02139 is in Cambridge, Massachusetts, in Middlesex County; area codes 617 and 857; Eastern time. Cambridge has 6 ZIP codes; the others are 02138, 02140, 02141, 02142 and 02238.

Type
Standard
Time zone
America/New_York
County
Middlesex
Population
40,033
Coordinates
42.3624, -71.1023
☼ Live from 02139 — Cambridge, MA

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Where 02139 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 02139
  • 🔢 Type 02139 into a pocket calculator and turn it upside down: GEIZO — not quite a word, sorry.
  • ➕ As a number, 2,139 = 3 × 23 × 31. Its digits add up to 15, a total 1,657 other ZIP codes share.
  • 💾In binary, the way a computer stores it: 100001011011
  • 🏠 Its numerical neighbours: 02138 (Cambridge, MA, 2 mi away) and 02140 (Cambridge, MA, 3 mi away).
  • 🔄 Backwards, 02139 becomes 93120 — and that is a real ZIP code: Santa Barbara, CA, 2,651 miles away.
  • 👥 65 other ZIP codes are made of exactly the same digits (01923, 03291, 09123, 09132, 09213, 10923, …). The farthest-flung twin is 09213 in APO AE, a military post office, 3,666 miles away.
  • 🧭 Farther north than 78% of all ZIP codes, and farther east than 96%.
  • 🎯1,435 miles east of the geographic center of the Lower 48, near Lebanon, Kansas.
  • 🌏 Dig straight through the Earth from 02139 and you would come out at 42.36°S, 108.90°E — 814 miles from Perth, Australia, the nearest big city to that spot.
  • ☀Longest day of the year: 15h 17m of daylight. Shortest: 9h 04m.
  • 📏 At 1.6 square miles of land, 02139 is bigger than 10% of ZIP codes — room for about 1.2 Central Parks.
🌙 The sky over 02139 today
  • Working out the sun…
🌋 Shake report
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Source: USGS.

People and housing

Population40,033This ZIP40,033
Households16,012This ZIP16,012
Housing units17,034This ZIP17,034
Median age30.0This ZIP30.0Massachusetts40.0US 38.9
Median household income$134,586This ZIP$134,586Massachusetts$103,960US $80,734
Median home value$1,087,500This ZIP$1,087,500Massachusetts$562,100US $332,700
Median gross rent$2,691This ZIP$2,691Massachusetts$1,762US $1,413
Bachelor's degree or higher79.5%This ZIP79.5%
Mean commute24.4 minThis ZIP24.4 min
Population density25,794.5 / sq miThis ZIP25,794.5 / sq mi

Business and tax activity

Business establishments1,118This ZIP1,118
Employees57,246This ZIP57,246
Annual payroll$7,655,080,000This ZIP$7,655,080,000
Tax returns filed18,550This ZIP18,550
Total adjusted gross income$2,348,476,000This ZIP$2,348,476,000

Land area

Land area1.55 sq miThis ZIP1.55 sq mi
Water area0.21 sq miThis ZIP0.21 sq mi

Other place names in 02139

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

ZIP codes near 02139

ZIPCityDistance
02238 Cambridge, MA 0.9 mi
02215 Boston, MA 1.0 mi
02142 Cambridge, MA 1.1 mi
02141 Cambridge, MA 1.1 mi
02163 Boston, MA 1.2 mi
02143 Somerville, MA 1.3 mi
02134 Allston, MA 1.4 mi
02199 Boston, MA 1.5 mi
02116 Boston, MA 1.5 mi
02115 Boston, MA 1.6 mi

Find every ZIP code within 10 miles of 02139 →

Questions about this ZIP code

Where is ZIP code 02139?

02139 is in Cambridge, Massachusetts, in Middlesex County, part of the Boston-Cambridge-Newton, MA-NH metropolitan area. Its published point location is 42.3624, -71.1023.

What county is 02139 in?

02139 lies in Middlesex County.

What area code is 02139?

Cambridge uses area codes 617 and 857, from NANPA's telephone records.

What time zone is 02139 in?

02139 uses America/New_York.

How many people live in 02139?

About 40,033 people live in ZIP code 02139, in 16,012 households, at 25,794.5 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 02139?

$134,586 a year, against $103,960 across Massachusetts.

What ZIP codes are near 02139?

The closest are 02238 (0.9 mi), 02215 (1 mi), 02142 (1.1 mi), 02141 (1.1 mi) and 02163 (1.2 mi).

Is 02139 a PO Box ZIP code?

02139 is a standard ZIP code. A normal ZIP code with street delivery.

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Cite this page

zipcodes.pro. “02139 ZIP Code — Cambridge, Massachusetts (Middlesex County).” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/zip/02139

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