🇺🇸 United States ZIP Code

STANDARD

94531

Antioch

ZIP Code 94531 is a standard zip code serving Antioch, Antioch, California (CA), in Contra Costa County, United States. It has an estimated population of 40,290 with a median household income of $87,927. The area falls within the America/Los_Angeles timezone.

Median Household Income vs. National Average

Location

Country: 🇺🇸 United States
State / Province: California (CA)
County: Contra Costa
City: Antioch
Timezone: America/Los_Angeles

Coordinates

Latitude: 37.965800
Longitude: -121.775800

Geographic Details

Land Area: 10.96 mi²
Population Density: 3678.0 people per mi² (90th percentile)
Bounding Box: 37.998152°N, 37.939387°S, -121.732538°E, -121.824053°W

With 40,290 residents spread across 10.96 square miles, this area has a population density of 3678.0 people per square mile.

Demographics

40,290

Population

95th percentile

$87,927

Median Income

90th percentile

$272,700

Median Home Value

85th percentile

10.96 mi²

Land Area

The median household income in 94531 is $87,927, and the median home value is $272,700. This places the area in the top 25% nationally for household income.

Housing

12,494

Total Units

11,639

Occupied Units

93.2%

Occupancy Rate

Nearby ZIP Codes

Other zip codes in Antioch, CA.

94509

Antioch

Similar ZIP Codes in California

ZIP codes with similar median household income in California.

92845

Garden Grove

$89,693

91344

Granada Hills

$77,604

91724

Covina

$77,198

95304

Tracy

$79,029

92860

Norco

$84,905

94542

Hayward

$84,817

90503

Torrance

$76,082

93720

Fresno

$75,200

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.