🇺🇸 United States ZIP Code

STANDARD

63366

O Fallon

ZIP Code 63366 is a standard zip code serving O Fallon, O Fallon, Missouri (MO), in Saint Charles County, United States. It has an estimated population of 46,175 with a median household income of $66,352. The area falls within the America/Chicago timezone.

Median Household Income vs. National Average

Location

Country: 🇺🇸 United States
State / Province: Missouri (MO)
County: Saint Charles
City: O Fallon
Timezone: America/Chicago

Coordinates

Latitude: 38.823900
Longitude: -90.742700

Geographic Details

Land Area: 68.75 mi²
Water Area: 1.33 mi²
Population Density: 672.0 people per mi² (75th percentile)
Bounding Box: 38.934235°N, 38.772805°S, -90.618210°E, -90.814293°W

With 46,175 residents spread across 68.75 square miles, this area has a population density of 672.0 people per square mile.

Demographics

46,175

Population

95th percentile

$66,352

Median Income

80th percentile

$180,200

Median Home Value

70th percentile

68.75 mi²

Land Area

The median household income in 63366 is $66,352, and the median home value is $180,200. This places the area in the top 25% nationally for household income.

Housing

17,758

Total Units

17,013

Occupied Units

95.8%

Occupancy Rate

Nearby ZIP Codes

Other zip codes in O Fallon, MO.

63368

O Fallon

Similar ZIP Codes in Missouri

ZIP codes with similar median household income in Missouri.

64063

Lees Summit

$63,065

63303

Saint Charles

$67,179

65255

Hallsville

$63,352

65039

Hartsburg

$67,481

64158

Kansas City

$73,125

63748

Frohna

$63,636

64015

Blue Springs

$64,344

63357

Marthasville

$64,757

Frequently Asked Questions

What information is available for each ZIP code?

Each ZIP code page shows city, state, county, geographic coordinates, timezone, population, median household income, median home value, housing units, land area, population density, commute time, educational attainment, area codes, and ZIP code type (Standard, PO Box, or Unique).

What are the different types of ZIP codes?

There are three types of ZIP codes: Standard (residential and commercial delivery areas), PO Box (assigned to post office box sections), and Unique (assigned to a single high-volume address like a government agency or large company). Standard ZIP codes are the most common.

How often is ZIP code data updated?

ZIP code assignments are updated quarterly by the USPS. Demographic data comes from the US Census Bureau's American Community Survey (ACS), which releases new 5-year estimates annually. ZipFYI updates its data to reflect the latest available information.

What is population density and why does it matter?

Population density measures the number of people per square mile in a ZIP code area. It helps identify urban vs. rural areas, affects real estate values, impacts service availability, and is used in market analysis. Dense urban ZIP codes may have 50,000+ people per square mile.

How are ZIP code boundaries determined?

ZIP code boundaries are determined by the USPS based on mail delivery routes, not political or geographic boundaries. They follow carrier routes and may cross city, county, or even state lines. Boundaries can change when the USPS reorganizes delivery operations.

What does median household income tell me about a ZIP code?

Median household income is the middle value when all household incomes in a ZIP code are sorted. Half of households earn more and half earn less. It is a better indicator of typical earnings than average income, which can be skewed by very high or very low outliers.