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/63303

63303

ZIP 63303 is in Saint Charles, Missouri, in St. Charles County; area code 636; Central time. Saint Charles has 4 ZIP codes; the others are 63301, 63302 and 63304.

Type
Standard
Time zone
America/Chicago
County
St. Charles
Metro area
St. Louis, MO-IL
Population
46,089
Coordinates
38.7398, -90.5437
☼ Live from 63303 — Saint Charles, MO

Weather right now

Asking the National Weather Service…

NEXRAD radar
Finding the nearest radar…
Local time: —

Where 63303 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 63303
  • 🔢 Type 63303 into a pocket calculator and turn it upside down: EOEEg — not quite a word, sorry.
  • ➕ As a number, 63,303 = 3 × 21101. Its digits add up to 15, a total 1,657 other ZIP codes share.
  • 💾In binary, the way a computer stores it: 1111011101000111
  • 🏠 Its numerical neighbours: 63302 (Saint Charles, MO, 5 mi away) and 63304 (Saint Charles, MO, 8 mi away).
  • 🔄 Backwards, 63303 becomes 30336 — and that is a real ZIP code: Atlanta, GA, 480 miles away.
  • 👥 14 other ZIP codes are made of exactly the same digits (06333, 30336, 30363, 30633, 33036, 33063, …). The farthest-flung twin is 33036 in Islamorada, FL, 1,116 miles away.
  • 🧭 Farther south than 53% of all ZIP codes, and farther west than 58%.
  • 🎯436 miles east of the geographic center of the Lower 48, near Lebanon, Kansas.
  • 🌏 Dig straight through the Earth from 63303 and you would come out at 38.74°S, 89.46°E — 1,198 miles from Port-aux-Français, French Southern Territories, the nearest big city to that spot.
  • ☀Longest day of the year: 14h 53m of daylight. Shortest: 9h 27m.
  • 📏 At 19.8 square miles of land, 63303 is bigger than 37% of ZIP codes — room for about 15 Central Parks.
🌙 The sky over 63303 today
  • Working out the sun…
🌋 Shake report
  • Checking the USGS…

Source: USGS.

People and housing

Population46,089This ZIP46,089
Households20,690This ZIP20,690
Housing units21,538This ZIP21,538
Median age41.4This ZIP41.4Missouri39.0US 38.9
Median household income$99,138This ZIP$99,138Missouri$70,702US $80,734
Median home value$321,100This ZIP$321,100Missouri$230,300US $332,700
Median gross rent$1,374This ZIP$1,374Missouri$1,033US $1,413
Bachelor's degree or higher48.8%This ZIP48.8%
Mean commute21.9 minThis ZIP21.9 min
Population density2,333.1 / sq miThis ZIP2,333.1 / sq mi

Business and tax activity

Business establishments950This ZIP950
Employees11,331This ZIP11,331
Annual payroll$483,780,000This ZIP$483,780,000
Tax returns filed23,940This ZIP23,940
Total adjusted gross income$2,237,527,000This ZIP$2,237,527,000

Land area

Land area19.75 sq miThis ZIP19.75 sq mi
Water area1.49 sq miThis ZIP1.49 sq mi

Other place names in 63303

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

ZIP codes near 63303

ZIPCityDistance
63346 Flinthill, MO 0.9 mi
63146 Saint Louis, MO 4.3 mi
63302 Saint Charles, MO 4.5 mi
63045 Earth City, MO 4.8 mi
63043 Maryland Heights, MO 4.8 mi
63006 Chesterfield, MO 5.6 mi
63376 Saint Peters, MO 5.6 mi
63017 Chesterfield, MO 5.8 mi
63338 Cottleville, MO 6.0 mi
63044 Bridgeton, MO 6.5 mi

Find every ZIP code within 10 miles of 63303 →

Questions about this ZIP code

Where is ZIP code 63303?

63303 is in Saint Charles, Missouri, in St. Charles County, part of the St. Louis, MO-IL metropolitan area. Its published point location is 38.7398, -90.5437.

What county is 63303 in?

63303 lies in St. Charles County.

What area code is 63303?

Saint Charles uses area code 636, from NANPA's telephone records.

What time zone is 63303 in?

63303 uses America/Chicago.

How many people live in 63303?

About 46,089 people live in ZIP code 63303, in 20,690 households, at 2,333.1 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 63303?

$99,138 a year, against $70,702 across Missouri.

What ZIP codes are near 63303?

The closest are 63346 (0.9 mi), 63146 (4.3 mi), 63302 (4.5 mi), 63045 (4.8 mi) and 63043 (4.8 mi).

Is 63303 a PO Box ZIP code?

63303 is a standard ZIP code. A normal ZIP code with street delivery.

Download or cite

Cite this page

zipcodes.pro. “63303 ZIP Code — Saint Charles, Missouri (St. Charles County).” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/zip/63303

Machine-readable version of these facts:

curl https://zipcodes.pro/zip/63303.json

Underlying data is public domain or openly licensed — sources, vintages and licences.