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zipcodes.pro — ZIP/91731

91731

ZIP 91731 is in El Monte, California, in Los Angeles County; area code 626; Pacific time. El Monte has 4 ZIP codes; the others are 91732, 91734 and 91735.

Type
Standard
Time zone
America/Los_Angeles
County
Los Angeles
Population
27,620
Coordinates
34.0786, -118.0435
☼ Live from 91731 — El Monte, CA

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Local time: —

Where 91731 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 91731
  • 🔢 Type 91731 into a pocket calculator and turn it upside down: IELIG — not quite a word, sorry.
  • ➕ As a number, 91,731 = 3 × 30577. Its digits add up to 21, a total 2,594 other ZIP codes share.
  • 💾In binary, the way a computer stores it: 10110011001010011
  • 🏠 Its numerical neighbours: 91730 (Rancho Cucamonga, CA, 26 mi away) and 91732 (El Monte, CA, 2 mi away).
  • 🔄 Backwards, 91731 becomes 13719, which is not a ZIP code at all.
  • 👥 29 other ZIP codes are made of exactly the same digits (11379, 11739, 11793, 11937, 11973, 17319, …). The farthest-flung twin is 11937 in East Hampton, NY, 2,527 miles away.
  • 🧭 Farther south than 78% of all ZIP codes, and farther west than 91%.
  • 🎯1,143 miles west of the geographic center of the Lower 48, near Lebanon, Kansas.
  • 🌏 Dig straight through the Earth from 91731 and you would come out at 34.08°S, 61.96°E — 995 miles from Saint-Denis, Reunion, the nearest big city to that spot.
  • ☀Longest day of the year: 14h 26m of daylight. Shortest: 9h 53m.
  • 📏 At 3.8 square miles of land, 91731 is bigger than 16% of ZIP codes — room for about 2.9 Central Parks.
🌙 The sky over 91731 today
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🌋 Shake report
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Source: USGS.

People and housing

Population27,620This ZIP27,620
Households8,293This ZIP8,293
Housing units8,648This ZIP8,648
Median age36.6This ZIP36.6California37.9US 38.9
Median household income$62,215This ZIP$62,215California$99,122US $80,734
Median home value$635,600This ZIP$635,600California$734,700US $332,700
Median gross rent$1,669This ZIP$1,669California$2,036US $1,413
Bachelor's degree or higher15.2%This ZIP15.2%
Mean commute29.3 minThis ZIP29.3 min
Population density7,278.0 / sq miThis ZIP7,278.0 / sq mi

Business and tax activity

Business establishments1,102This ZIP1,102
Employees15,623This ZIP15,623
Annual payroll$945,858,000This ZIP$945,858,000
Tax returns filed12,130This ZIP12,130
Total adjusted gross income$583,210,000This ZIP$583,210,000

Land area

Land area3.80 sq miThis ZIP3.80 sq mi
Water area0.06 sq miThis ZIP0.06 sq mi

Other place names in 91731

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

ZIP codes near 91731

ZIPCityDistance
91734 El Monte, CA 1.1 mi
91735 El Monte, CA 1.1 mi
91771 Rosemead, CA 1.7 mi
91772 Rosemead, CA 1.7 mi
91732 El Monte, CA 1.7 mi
91780 Temple City, CA 1.7 mi
91733 South El Monte, CA 2.3 mi
91770 Rosemead, CA 2.4 mi
91776 San Gabriel, CA 3.0 mi
91007 Arcadia, CA 3.4 mi

Find every ZIP code within 10 miles of 91731 →

Questions about this ZIP code

Where is ZIP code 91731?

91731 is in El Monte, California, in Los Angeles County, part of the Los Angeles-Long Beach-Anaheim, CA metropolitan area. Its published point location is 34.0786, -118.0435.

What county is 91731 in?

91731 lies in Los Angeles County.

What area code is 91731?

El Monte uses area code 626, from NANPA's telephone records.

What time zone is 91731 in?

91731 uses America/Los_Angeles.

How many people live in 91731?

About 27,620 people live in ZIP code 91731, in 8,293 households, at 7,278.0 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 91731?

$62,215 a year, against $99,122 across California.

What ZIP codes are near 91731?

The closest are 91734 (1.1 mi), 91735 (1.1 mi), 91771 (1.7 mi), 91772 (1.7 mi) and 91732 (1.7 mi).

Is 91731 a PO Box ZIP code?

91731 is a standard ZIP code. A normal ZIP code with street delivery.

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zipcodes.pro. “91731 ZIP Code — El Monte, California (Los Angeles County).” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/zip/91731

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