Every ZIP code in the United States, with weather, radar, trivia and the numbers behind it. Five digits since 1963!

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/77491

77491

ZIP 77491 is in Katy, Texas, in Harris County; area codes 281, 346 and 832; Central time. Katy has 6 ZIP codes; the others are 77449, 77450, 77492, 77493 and 77494.

Type
No street area
Time zone
America/Chicago
County
Harris
Coordinates
29.7858, -95.8244

The Census map gives this ZIP code no delivery area of its own, which usually means it serves post office boxes, a single organization or a post office rather than streets of homes.

This ZIP code has no Census tabulation area of its own. Its point falls inside ZCTA 77493, whose figures describe that area — not this ZIP code.

☼ Live from 77491 — Katy, TX

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Where 77491 is

This ZIP code has no Census tabulation area, so there is no boundary to draw — the marker is its published point location.

★ Weird and wonderful facts about 77491
  • 🔢 Type 77491 into a pocket calculator and turn it upside down: IGhLL — not quite a word, sorry.
  • ➕ 77491 is a prime number. It cannot be divided by anything except 1 and itself. Its digits add up to 28, a total 1,520 other ZIP codes share.
  • 💾In binary, the way a computer stores it: 10010111010110011
  • 🏠 Its numerical neighbours: 77489 (Missouri City, TX, 23 mi away) and 77492 (Katy, TX, 0 mi away).
  • 🔄 Backwards, 77491 becomes 19477 — and that is a real ZIP code: Spring House, PA, 1,364 miles away.
  • 👥 21 other ZIP codes are made of exactly the same digits (14779, 17749, 17974, 19477, 47719, 47917, …). The farthest-flung twin is 97147 in Wheeler, OR, 1,870 miles away.
  • 🧭 Farther south than 94% of all ZIP codes, and farther west than 71%.
  • 🎯711 miles south of the geographic center of the Lower 48, near Lebanon, Kansas.
  • 🌏 Dig straight through the Earth from 77491 and you would come out at 29.79°S, 84.18°E — 1,463 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.
🌙 The sky over 77491 today
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🌋 Shake report
  • Checking the USGS…

Source: USGS.

Business and tax activity

Business establishments4This ZIP4
Employees14This ZIP14
Annual payroll$478,000This ZIP$478,000

Land area

ZIP codes near 77491

ZIPCityDistance
77492 Katy, TX 0.0 mi
77494 Katy, TX 2.9 mi
77493 Katy, TX 4.7 mi
77450 Katy, TX 5.9 mi
77449 Katy, TX 6.5 mi
77094 Houston, TX 7.6 mi
77441 Fulshear, TX 8.0 mi
77413 Barker, TX 8.4 mi
77406 Richmond, TX 9.8 mi
77084 Houston, TX 10.3 mi

Find every ZIP code within 10 miles of 77491 →

Questions about this ZIP code

Where is ZIP code 77491?

77491 is in Katy, Texas, in Harris County, part of the Houston-Pasadena-The Woodlands, TX metropolitan area. Its published point location is 29.7858, -95.8244.

What county is 77491 in?

77491 lies in Harris County.

What area code is 77491?

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

What time zone is 77491 in?

77491 uses America/Chicago.

What ZIP codes are near 77491?

The closest are 77492 (0 mi), 77494 (2.9 mi), 77493 (4.7 mi), 77450 (5.9 mi) and 77449 (6.5 mi).

Is 77491 a PO Box ZIP code?

Possibly. The Census map gives this ZIP code no delivery area of its own, which usually means it serves post office boxes, a single organization or a post office rather than streets of homes.

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Cite this page

zipcodes.pro. “77491 ZIP Code — Katy, Texas (Harris County).” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/zip/77491

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curl https://zipcodes.pro/zip/77491.json

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