🇺🇸 United States ZIP Code

STANDARD

94403

San Mateo

ZIP Code 94403 is a standard zip code serving San Mateo, San Mateo, California (CA), in San Mateo County, United States. It has an estimated population of 39,642 with a median household income of $90,764. The area falls within the America/Los_Angeles timezone.

Median Household Income vs. National Average

Location

Country: 🇺🇸 United States
State / Province: California (CA)
County: San Mateo
City: San Mateo
Timezone: America/Los_Angeles

Coordinates

Latitude: 37.539500
Longitude: -122.299800

Geographic Details

Land Area: 5.63 mi²
Water Area: 0.17 mi²
Population Density: 7040.0 people per mi² (95th percentile)
Bounding Box: 37.568005°N, 37.511739°S, -122.274974°E, -122.332738°W

With 39,642 residents spread across 5.63 square miles, this area has a population density of 7040.0 people per square mile.

Demographics

39,642

Population

95th percentile

$90,764

Median Income

90th percentile

$755,400

Median Home Value

95th percentile

5.63 mi²

Land Area

The median household income in 94403 is $90,764, and the median home value is $755,400. This places the area in the top 25% nationally for household income.

Housing

16,371

Total Units

15,729

Occupied Units

96.1%

Occupancy Rate

Nearby ZIP Codes

Other zip codes in San Mateo, CA.

94401

San Mateo

94402

San Mateo

94404

San Mateo

94497

San Mateo

Similar ZIP Codes in California

ZIP codes with similar median household income in California.

95123

San Jose

$87,180

93314

Bakersfield

$95,830

94020

La Honda

$99,716

92124

San Diego

$80,463

92688

Rancho Santa Margarita

$98,821

92807

Anaheim

$98,027

92010

Carlsbad

$90,417

94118

San Francisco

$82,857

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.