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zipcodes.pro — ZIP/02138

02138

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

Type
Standard
Time zone
America/New_York
County
Middlesex
Population
38,509
Coordinates
42.3796, -71.1352
☼ Live from 02138 — Cambridge, MA

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Where 02138 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 02138
  • 🔢 Type 02138 into a pocket calculator and turn it upside down: BEIZO — not quite a word, sorry.
  • ➕ As a number, 2,138 = 2 × 1069. Its digits add up to 14, a total 1,416 other ZIP codes share.
  • 💾In binary, the way a computer stores it: 100001011010
  • 🏠 Its numerical neighbours: 02137 (Readville, MA, 10 mi away) and 02139 (Cambridge, MA, 2 mi away).
  • 🔄 Backwards, 02138 becomes 83120 — and that is a real ZIP code: Freedom, WY, 2,011 miles away.
  • 👥 70 other ZIP codes are made of exactly the same digits (01238, 01832, 02381, 02813, 02831, 03218, …). The farthest-flung twin is 83210 in Aberdeen, ID, 2,097 miles away.
  • 🧭 Farther north than 78% of all ZIP codes, and farther east than 96%.
  • 🎯1,433 miles east of the geographic center of the Lower 48, near Lebanon, Kansas.
  • 🌏 Dig straight through the Earth from 02138 and you would come out at 42.38°S, 108.86°E — 816 miles from Perth, Australia, the nearest big city to that spot.
  • ☀Longest day of the year: 15h 17m of daylight. Shortest: 9h 04m.
  • 📏 At 2.7 square miles of land, 02138 is bigger than 14% of ZIP codes — room for about 2.1 Central Parks.
🌙 The sky over 02138 today
  • Working out the sun…
🌋 Shake report
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Source: USGS.

People and housing

Population38,509This ZIP38,509
Households14,169This ZIP14,169
Housing units16,043This ZIP16,043
Median age28.3This ZIP28.3Massachusetts40.0US 38.9
Median household income$119,967This ZIP$119,967Massachusetts$103,960US $80,734
Median home value$1,212,400This ZIP$1,212,400Massachusetts$562,100US $332,700
Median gross rent$2,772This ZIP$2,772Massachusetts$1,762US $1,413
Bachelor's degree or higher85.6%This ZIP85.6%
Mean commute23.6 minThis ZIP23.6 min
Population density14,064.6 / sq miThis ZIP14,064.6 / sq mi

Business and tax activity

Business establishments1,072This ZIP1,072
Employees46,771This ZIP46,771
Annual payroll$3,706,071,000This ZIP$3,706,071,000
Tax returns filed14,470This ZIP14,470
Total adjusted gross income$4,058,990,000This ZIP$4,058,990,000

Land area

Land area2.74 sq miThis ZIP2.74 sq mi
Water area0.33 sq miThis ZIP0.33 sq mi

Other place names in 02138

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

ZIP codes near 02138

ZIPCityDistance
02140 Cambridge, MA 0.9 mi
02163 Boston, MA 1.0 mi
02134 Allston, MA 1.5 mi
02238 Cambridge, MA 1.5 mi
02144 Somerville, MA 1.5 mi
02143 Somerville, MA 2.0 mi
02139 Cambridge, MA 2.1 mi
02135 Brighton, MA 2.3 mi
02472 Watertown, MA 2.3 mi
02145 Somerville, MA 2.5 mi

Find every ZIP code within 10 miles of 02138 →

Questions about this ZIP code

Where is ZIP code 02138?

02138 is in Cambridge, Massachusetts, in Middlesex County, part of the Boston-Cambridge-Newton, MA-NH metropolitan area. Its published point location is 42.3796, -71.1352.

What county is 02138 in?

02138 lies in Middlesex County.

What area code is 02138?

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

What time zone is 02138 in?

02138 uses America/New_York.

How many people live in 02138?

About 38,509 people live in ZIP code 02138, in 14,169 households, at 14,064.6 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 02138?

$119,967 a year, against $103,960 across Massachusetts.

What ZIP codes are near 02138?

The closest are 02140 (0.9 mi), 02163 (1 mi), 02134 (1.5 mi), 02238 (1.5 mi) and 02144 (1.5 mi).

Is 02138 a PO Box ZIP code?

02138 is a standard ZIP code. A normal ZIP code with street delivery.

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Cite this page

zipcodes.pro. “02138 ZIP Code — Cambridge, Massachusetts (Middlesex County).” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/zip/02138

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