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zipcodes.pro — ZIP/63123

63123

ZIP 63123 is in Saint Louis, Missouri, mostly in St. Louis County; area codes 314 and 557; Central time. Saint Louis has 68 ZIP codes in all.

Type
Standard
Time zone
America/Chicago
County
St. Louis +1 more
Metro area
St. Louis, MO-IL
Population
49,077
Coordinates
38.5474, -90.3281
☼ Live from 63123 — Saint Louis, MO

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Where 63123 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 63123
  • 🔢 Type 63123 into a pocket calculator and turn it upside down: EZIEg — not quite a word, sorry.
  • ➕ As a number, 63,123 = 3 × 53 × 397. Its digits add up to 15, a total 1,657 other ZIP codes share.
  • 💾In binary, the way a computer stores it: 1111011010010011
  • 🏠 Its numerical neighbours: 63122 (Saint Louis, MO, 5 mi away) and 63124 (Saint Louis, MO, 7 mi away).
  • 🔄 Backwards, 63123 becomes 32136 — and that is a real ZIP code: Flagler Beach, FL, 818 miles away.
  • 👥 32 other ZIP codes are made of exactly the same digits (13326, 13362, 13623, 13632, 16233, 16323, …). The farthest-flung twin is 33261 in Miami, FL, 1,062 miles away.
  • 🧭 Farther south than 55% of all ZIP codes, and farther west than 57%.
  • 🎯450 miles east of the geographic center of the Lower 48, near Lebanon, Kansas.
  • 🌏 Dig straight through the Earth from 63123 and you would come out at 38.55°S, 89.67°E — 1,216 miles from Port-aux-Français, French Southern Territories, the nearest big city to that spot.
  • ☀Longest day of the year: 14h 52m of daylight. Shortest: 9h 28m.
  • 📏 At 12.5 square miles of land, 63123 is bigger than 30% of ZIP codes — room for about 9.5 Central Parks.
🌙 The sky over 63123 today
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🌋 Shake report
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Source: USGS.

People and housing

Population49,077This ZIP49,077
Households21,755This ZIP21,755
Housing units23,178This ZIP23,178
Median age40.9This ZIP40.9Missouri39.0US 38.9
Median household income$77,055This ZIP$77,055Missouri$70,702US $80,734
Median home value$219,400This ZIP$219,400Missouri$230,300US $332,700
Median gross rent$1,006This ZIP$1,006Missouri$1,033US $1,413
Bachelor's degree or higher37.6%This ZIP37.6%
Mean commute23.7 minThis ZIP23.7 min
Population density3,940.7 / sq miThis ZIP3,940.7 / sq mi

Business and tax activity

Business establishments915This ZIP915
Employees13,475This ZIP13,475
Annual payroll$767,582,000This ZIP$767,582,000
Tax returns filed26,750This ZIP26,750
Total adjusted gross income$1,860,495,000This ZIP$1,860,495,000

Land area

Land area12.45 sq miThis ZIP12.45 sq mi
Water area0.10 sq miThis ZIP0.10 sq mi

Counties 63123 spans

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

CountyShare of this ZIP
St. Louis County 95.0%
St. Louis city 5.0%

Other place names in 63123

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

ZIP codes near 63123

ZIPCityDistance
63125 Saint Louis, MO 2.7 mi
63126 Saint Louis, MO 2.7 mi
63109 Saint Louis, MO 3.1 mi
63119 Saint Louis, MO 3.2 mi
63116 Saint Louis, MO 4.1 mi
63111 Saint Louis, MO 4.3 mi
63143 Saint Louis, MO 4.5 mi
63139 Saint Louis, MO 4.8 mi
63127 Saint Louis, MO 4.9 mi
63128 Saint Louis, MO 5.0 mi

Find every ZIP code within 10 miles of 63123 →

Questions about this ZIP code

Where is ZIP code 63123?

63123 is in Saint Louis, Missouri, in St. Louis County, part of the St. Louis, MO-IL metropolitan area. Its published point location is 38.5474, -90.3281.

What county is 63123 in?

63123 spans 2 counties: St. Louis County and St. Louis city. Most of it falls in St. Louis 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 63123?

Saint Louis uses area codes 314 and 557, from NANPA's telephone records.

What time zone is 63123 in?

63123 uses America/Chicago.

How many people live in 63123?

About 49,077 people live in ZIP code 63123, in 21,755 households, at 3,940.7 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 63123?

$77,055 a year, against $70,702 across Missouri.

What ZIP codes are near 63123?

The closest are 63125 (2.7 mi), 63126 (2.7 mi), 63109 (3.1 mi), 63119 (3.2 mi) and 63116 (4.1 mi).

Is 63123 a PO Box ZIP code?

63123 is a standard ZIP code. A normal ZIP code with street delivery.

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Cite this page

zipcodes.pro. “63123 ZIP Code — Saint Louis, Missouri (St. Louis County).” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/zip/63123

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