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zipcodes.pro — ZIP/77521

77521

ZIP 77521 is in Baytown, Texas, mostly in Harris County; area codes 281, 346, 832 and 713; Central time. Baytown has 4 ZIP codes; the others are 77520, 77522 and 77523.

Type
Standard
Time zone
America/Chicago
County
Harris +1 more
Population
69,038
Coordinates
29.8119, -94.9633
☼ Live from 77521 — Baytown, TX

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Local time: —

Where 77521 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 77521
  • 🔢 Type 77521 into a pocket calculator and turn it upside down: IZSLL — not quite a word, sorry.
  • ➕ 77521 is a prime number. It cannot be divided by anything except 1 and itself. Its digits add up to 22, a total 2,607 other ZIP codes share.
  • 💾In binary, the way a computer stores it: 10010111011010001
  • 🏠 Its numerical neighbours: 77520 (Baytown, TX, 6 mi away) and 77522 (Baytown, TX, 5 mi away).
  • 🔄 Backwards, 77521 becomes 12577 — and that is a real ZIP code: Salisbury Mills, NY, 1,413 miles away.
  • 👥 37 other ZIP codes are made of exactly the same digits (12577, 12775, 15277, 15727, 15772, 17257, …). The farthest-flung twin is 12577 in Salisbury Mills, NY, 1,413 miles away.
  • 🧭 Farther south than 94% of all ZIP codes, and farther west than 68%.
  • 🎯722 miles south of the geographic center of the Lower 48, near Lebanon, Kansas.
  • 🌏 Dig straight through the Earth from 77521 and you would come out at 29.81°S, 85.04°E — 1,435 miles from West Island, Cocos Islands, the nearest big city to that spot.
  • ☀Longest day of the year: 14h 04m of daylight. Shortest: 10h 14m.
  • 📏 At 49.3 square miles of land, 77521 is bigger than 59% of ZIP codes — room for about 37 Central Parks.
🌙 The sky over 77521 today
  • Working out the sun…
🌋 Shake report
  • Checking the USGS…

Source: USGS.

People and housing

Population69,038This ZIP69,038
Households24,321This ZIP24,321
Housing units25,879This ZIP25,879
Median age32.9This ZIP32.9Texas35.6US 38.9
Median household income$73,629This ZIP$73,629Texas$78,476US $80,734
Median home value$231,400This ZIP$231,400Texas$283,800US $332,700
Median gross rent$1,390This ZIP$1,390Texas$1,403US $1,413
Bachelor's degree or higher16.9%This ZIP16.9%
Mean commute25.2 minThis ZIP25.2 min
Population density1,401.2 / sq miThis ZIP1,401.2 / sq mi

Business and tax activity

Business establishments908This ZIP908
Employees17,772This ZIP17,772
Annual payroll$966,801,000This ZIP$966,801,000
Tax returns filed29,110This ZIP29,110
Total adjusted gross income$1,855,618,000This ZIP$1,855,618,000

Land area

Land area49.27 sq miThis ZIP49.27 sq mi
Water area0.93 sq miThis ZIP0.93 sq mi

Counties 77521 spans

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

CountyShare of this ZIP
Harris County 77.3%
Chambers County 22.7%

Other place names in 77521

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

ZIP codes near 77521

ZIPCityDistance
77522 Baytown, TX 5.3 mi
77562 Highlands, TX 5.6 mi
77520 Baytown, TX 5.7 mi
77580 Mont Belvieu, TX 6.0 mi
77523 Baytown, TX 6.6 mi
77530 Channelview, TX 9.2 mi
77532 Crosby, TX 10.1 mi
77571 La Porte, TX 10.2 mi
77572 La Porte, TX 10.6 mi
77049 Houston, TX 11.2 mi

Find every ZIP code within 10 miles of 77521 →

Questions about this ZIP code

Where is ZIP code 77521?

77521 is in Baytown, Texas, in Harris County, part of the Houston-Pasadena-The Woodlands, TX metropolitan area. Its published point location is 29.8119, -94.9633.

What county is 77521 in?

77521 spans 2 counties: Harris County and Chambers County. Most of it falls in Harris 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 77521?

Baytown uses area codes 281, 346, 832 and 713, from NANPA's telephone records.

What time zone is 77521 in?

77521 uses America/Chicago.

How many people live in 77521?

About 69,038 people live in ZIP code 77521, in 24,321 households, at 1,401.2 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 77521?

$73,629 a year, against $78,476 across Texas.

What ZIP codes are near 77521?

The closest are 77522 (5.3 mi), 77562 (5.6 mi), 77520 (5.7 mi), 77580 (6 mi) and 77523 (6.6 mi).

Is 77521 a PO Box ZIP code?

77521 is a standard ZIP code. A normal ZIP code with street delivery.

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Cite this page

zipcodes.pro. “77521 ZIP Code — Baytown, Texas (Harris County).” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/zip/77521

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