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zipcodes.pro — ZIP/78655

78655

ZIP 78655 is Martindale, Texas, mostly in Caldwell County; area codes 737 and 512; Central time.

Type
Standard
Time zone
America/Chicago
County
Caldwell +1 more
Population
3,730
Coordinates
29.8161, -97.8351
☼ Live from 78655 — Martindale, TX

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Local time: —

Where 78655 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 78655
  • 🔢 Type 78655 into a pocket calculator and turn it upside down: SSgBL — not quite a word, sorry.
  • ➕ As a number, 78,655 = 5 × 15731. Its digits add up to 31, a total 799 other ZIP codes share.
  • 💾In binary, the way a computer stores it: 10011001100111111
  • 🏠 Its numerical neighbours: 78654 (Marble Falls, TX, 57 mi away) and 78656 (Maxwell, TX, 6 mi away).
  • 🔄 Backwards, 78655 becomes 55687, which is not a ZIP code at all.
  • 👥 25 other ZIP codes are made of exactly the same digits (55768, 55786, 56578, 56587, 56758, 57568, …). The farthest-flung twin is 58765 in Noonan, ND, 1,345 miles away.
  • 🧭 Farther south than 94% of all ZIP codes, and farther west than 77%.
  • 🎯693 miles south of the geographic center of the Lower 48, near Lebanon, Kansas.
  • 🌏 Dig straight through the Earth from 78655 and you would come out at 29.82°S, 82.16°E — 1,488 miles from Port-aux-Français, French Southern Territories, the nearest big city to that spot.
  • ☀Longest day of the year: 14h 04m of daylight. Shortest: 10h 14m.
  • 📏 At 28.7 square miles of land, 78655 is bigger than 45% of ZIP codes — room for about 22 Central Parks.
🌙 The sky over 78655 today
  • Working out the sun…
🌋 Shake report
  • Checking the USGS…

Source: USGS.

People and housing

Population3,730This ZIP3,730
Households1,388This ZIP1,388
Housing units1,433This ZIP1,433
Median age44.6This ZIP44.6Texas35.6US 38.9
Median household income$55,952This ZIP$55,952Texas$78,476US $80,734
Median home value$269,900This ZIP$269,900Texas$283,800US $332,700
Median gross rent$1,093This ZIP$1,093Texas$1,403US $1,413
Bachelor's degree or higher20.1%This ZIP20.1%
Mean commute33.4 minThis ZIP33.4 min
Population density130.1 / sq miThis ZIP130.1 / sq mi

Business and tax activity

Business establishments44This ZIP44
Employees190This ZIP190
Annual payroll$7,059,000This ZIP$7,059,000
Tax returns filed1,350This ZIP1,350
Total adjusted gross income$93,553,000This ZIP$93,553,000

Land area

Land area28.68 sq miThis ZIP28.68 sq mi
Water area0.24 sq miThis ZIP0.24 sq mi

Counties 78655 spans

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

CountyShare of this ZIP
Caldwell County 60.0%
Guadalupe County 40.0%

Other place names in 78655

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

ZIP codes near 78655

ZIPCityDistance
78670 Staples, TX 3.6 mi
78622 Fentress, TX 4.1 mi
78656 Maxwell, TX 6.3 mi
78661 Prairie Lea, TX 7.9 mi
78666 San Marcos, TX 10.1 mi
78644 Lockhart, TX 10.4 mi
78638 Kingsbury, TX 11.2 mi
78640 Kyle, TX 12.4 mi
78648 Luling, TX 14.5 mi
78156 Seguin, TX 16.3 mi

Find every ZIP code within 10 miles of 78655 →

Questions about this ZIP code

Where is ZIP code 78655?

78655 is in Martindale, Texas, in Caldwell County, part of the Austin-Round Rock-San Marcos, TX metropolitan area. Its published point location is 29.8161, -97.8351.

What county is 78655 in?

78655 spans 2 counties: Caldwell County and Guadalupe County. Most of it falls in Caldwell 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 78655?

Martindale uses area codes 737 and 512, from NANPA's telephone records.

What time zone is 78655 in?

78655 uses America/Chicago.

How many people live in 78655?

About 3,730 people live in ZIP code 78655, in 1,388 households, at 130.1 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 78655?

$55,952 a year, against $78,476 across Texas.

What ZIP codes are near 78655?

The closest are 78670 (3.6 mi), 78622 (4.1 mi), 78656 (6.3 mi), 78661 (7.9 mi) and 78666 (10.1 mi).

Is 78655 a PO Box ZIP code?

78655 is a standard ZIP code. A normal ZIP code with street delivery.

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Cite this page

zipcodes.pro. “78655 ZIP Code — Martindale, Texas (Caldwell County).” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/zip/78655

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