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zipcodes.pro — ZIP/78231

78231

ZIP 78231 is in San Antonio, Texas, in Bexar County; area codes 210 and 726; Central time. San Antonio has 83 ZIP codes in all.

Type
Standard
Time zone
America/Chicago
County
Bexar
Population
9,744
Coordinates
29.5810, -98.5425
☼ Live from 78231 — San Antonio, TX

Weather right now

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Local time: —

Where 78231 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 78231
  • 🔢 Type 78231 into a pocket calculator and turn it upside down: IEZBL — not quite a word, sorry.
  • ➕ As a number, 78,231 = 3 × 89 × 293. Its digits add up to 21, a total 2,594 other ZIP codes share.
  • 💾In binary, the way a computer stores it: 10011000110010111
  • 🏠 Its numerical neighbours: 78230 (San Antonio, TX, 3 mi away) and 78232 (San Antonio, TX, 4 mi away).
  • 🔄 Backwards, 78231 becomes 13287, which is not a ZIP code at all.
  • 👥 56 other ZIP codes are made of exactly the same digits (12738, 12783, 12837, 12873, 13782, 13827, …). The farthest-flung twin is 12837 in Hampton, NY, 1,690 miles away.
  • 🧭 Farther south than 94% of all ZIP codes, and farther west than 78%.
  • 🎯708 miles south of the geographic center of the Lower 48, near Lebanon, Kansas.
  • 🌏 Dig straight through the Earth from 78231 and you would come out at 29.58°S, 81.46°E — 1,488 miles from Port-aux-Français, French Southern Territories, the nearest big city to that spot.
  • ☀Longest day of the year: 14h 03m of daylight. Shortest: 10h 15m.
  • 📏 At 4.1 square miles of land, 78231 is bigger than 17% of ZIP codes — room for about 3.1 Central Parks.
🌙 The sky over 78231 today
  • Working out the sun…
🌋 Shake report
  • Checking the USGS…

Source: USGS.

People and housing

Population9,744This ZIP9,744
Households3,978This ZIP3,978
Housing units4,083This ZIP4,083
Median age41.2This ZIP41.2Texas35.6US 38.9
Median household income$109,183This ZIP$109,183Texas$78,476US $80,734
Median home value$401,800This ZIP$401,800Texas$283,800US $332,700
Median gross rent$1,393This ZIP$1,393Texas$1,403US $1,413
Bachelor's degree or higher65.7%This ZIP65.7%
Mean commute20.5 minThis ZIP20.5 min
Population density2,383.0 / sq miThis ZIP2,383.0 / sq mi

Business and tax activity

Business establishments359This ZIP359
Employees4,196This ZIP4,196
Annual payroll$251,033,000This ZIP$251,033,000
Tax returns filed4,440This ZIP4,440
Total adjusted gross income$1,007,722,000This ZIP$1,007,722,000

Land area

Land area4.09 sq miThis ZIP4.09 sq mi
Water area0.01 sq miThis ZIP0.01 sq mi

Other place names in 78231

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

ZIP codes near 78231

ZIPCityDistance
78248 San Antonio, TX 1.2 mi
78230 San Antonio, TX 2.5 mi
78232 San Antonio, TX 4.0 mi
78216 San Antonio, TX 4.2 mi
78249 San Antonio, TX 4.5 mi
78213 San Antonio, TX 4.6 mi
78258 San Antonio, TX 4.9 mi
78257 San Antonio, TX 5.1 mi
78240 San Antonio, TX 5.4 mi
78229 San Antonio, TX 5.6 mi

Find every ZIP code within 10 miles of 78231 →

Questions about this ZIP code

Where is ZIP code 78231?

78231 is in San Antonio, Texas, in Bexar County, part of the San Antonio-New Braunfels, TX metropolitan area. Its published point location is 29.5810, -98.5425.

What county is 78231 in?

78231 lies in Bexar County.

What area code is 78231?

San Antonio uses area codes 210 and 726, from NANPA's telephone records.

What time zone is 78231 in?

78231 uses America/Chicago.

How many people live in 78231?

About 9,744 people live in ZIP code 78231, in 3,978 households, at 2,383.0 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 78231?

$109,183 a year, against $78,476 across Texas.

What ZIP codes are near 78231?

The closest are 78248 (1.2 mi), 78230 (2.5 mi), 78232 (4 mi), 78216 (4.2 mi) and 78249 (4.5 mi).

Is 78231 a PO Box ZIP code?

78231 is a standard ZIP code. A normal ZIP code with street delivery.

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Cite this page

zipcodes.pro. “78231 ZIP Code — San Antonio, Texas (Bexar County).” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/zip/78231

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