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ZIP stands for Zone Improvement Plan. The codes went live on July 1, 1963.The lowest ZIP code is 00501 — the IRS in Holtsville, New York.The highest ZIP code is 99950, in Ketchikan, Alaska.Type 07734 into a calculator and turn it upside down: hELLO. It is Keansburg, New Jersey.12345 belongs to one company: General Electric in Schenectady, New York.The first digit is a region: 0 is New England and New Jersey, 9 is the West Coast, Alaska and Hawaii.Mr. ZIP, the cartoon mailman, was the mascot that sold the idea to America.ZIP+4 arrived in 1983 and can narrow a ZIP down to one side of one block.A ZIP code is a mail route, not a place: plenty of them cross county and even state lines.Play ZIP Hunt: guess the secret ZIP code of the day in six tries.
zipcodes.pro — ZIP/01851

01851

ZIP 01851 is in Lowell, Massachusetts, in Middlesex County; area codes 978 and 351; Eastern time. Lowell has 5 ZIP codes; the others are 01850, 01852, 01853 and 01854.

Type
Standard
Time zone
America/New_York
County
Middlesex
Population
33,403
Coordinates
42.6280, -71.3368
☼ Live from 01851 — Lowell, MA

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Local time: —

Where 01851 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 01851
  • 🔢 Type 01851 into a pocket calculator and turn it upside down: ISBIO — not quite a word, sorry.
  • ➕ As a number, 1,851 = 3 × 617. Its digits add up to 15, a total 1,657 other ZIP codes share.
  • 💾In binary, the way a computer stores it: 11100111011
  • 🏠 Its numerical neighbours: 01850 (Lowell, MA, 3 mi away) and 01852 (Lowell, MA, 2 mi away).
  • 🔄 Backwards, 01851 becomes 15810, which is not a ZIP code at all.
  • 👥 25 other ZIP codes are made of exactly the same digits (01518, 01581, 01815, 08511, 10158, 10185, …). The farthest-flung twin is 85011 in Phoenix, AZ, 2,282 miles away.
  • 🧭 Farther north than 80% of all ZIP codes, and farther east than 95%.
  • 🎯1,423 miles east of the geographic center of the Lower 48, near Lebanon, Kansas.
  • 🌏 Dig straight through the Earth from 01851 and you would come out at 42.63°S, 108.66°E — 836 miles from Perth, Australia, the nearest big city to that spot.
  • ☀Longest day of the year: 15h 19m of daylight. Shortest: 9h 03m.
  • 📏 At 3.2 square miles of land, 01851 is bigger than 15% of ZIP codes — room for about 2.5 Central Parks.
🌙 The sky over 01851 today
  • Working out the sun…
🌋 Shake report
  • Checking the USGS…

Source: USGS.

People and housing

Population33,403This ZIP33,403
Households11,421This ZIP11,421
Housing units11,853This ZIP11,853
Median age36.4This ZIP36.4Massachusetts40.0US 38.9
Median household income$92,401This ZIP$92,401Massachusetts$103,960US $80,734
Median home value$467,000This ZIP$467,000Massachusetts$562,100US $332,700
Median gross rent$1,714This ZIP$1,714Massachusetts$1,762US $1,413
Bachelor's degree or higher30.2%This ZIP30.2%
Mean commute28.8 minThis ZIP28.8 min
Population density10,344.7 / sq miThis ZIP10,344.7 / sq mi

Business and tax activity

Business establishments477This ZIP477
Employees13,356This ZIP13,356
Annual payroll$1,707,284,000This ZIP$1,707,284,000
Tax returns filed16,390This ZIP16,390
Total adjusted gross income$981,829,000This ZIP$981,829,000

Land area

Land area3.23 sq miThis ZIP3.23 sq mi
Water area0.11 sq miThis ZIP0.11 sq mi

Other place names in 01851

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

ZIP codes near 01851

ZIPCityDistance
01853 Lowell, MA 1.1 mi
01854 Lowell, MA 1.6 mi
01852 Lowell, MA 2.1 mi
01850 Lowell, MA 2.6 mi
01824 Chelmsford, MA 2.7 mi
01863 North Chelmsford, MA 3.1 mi
01862 North Billerica, MA 4.0 mi
01826 Dracut, MA 4.0 mi
01879 Tyngsboro, MA 5.4 mi
01876 Tewksbury, MA 5.7 mi

Find every ZIP code within 10 miles of 01851 →

Questions about this ZIP code

Where is ZIP code 01851?

01851 is in Lowell, Massachusetts, in Middlesex County, part of the Boston-Cambridge-Newton, MA-NH metropolitan area. Its published point location is 42.6280, -71.3368.

What county is 01851 in?

01851 lies in Middlesex County.

What area code is 01851?

Lowell uses area codes 978 and 351, from NANPA's telephone records.

What time zone is 01851 in?

01851 uses America/New_York.

How many people live in 01851?

About 33,403 people live in ZIP code 01851, in 11,421 households, at 10,344.7 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 01851?

$92,401 a year, against $103,960 across Massachusetts.

What ZIP codes are near 01851?

The closest are 01853 (1.1 mi), 01854 (1.6 mi), 01852 (2.1 mi), 01850 (2.6 mi) and 01824 (2.7 mi).

Is 01851 a PO Box ZIP code?

01851 is a standard ZIP code. A normal ZIP code with street delivery.

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Cite this page

zipcodes.pro. “01851 ZIP Code — Lowell, Massachusetts (Middlesex County).” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/zip/01851

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