🇺🇸 United States ZIP Code

STANDARD

91108

San Marino

ZIP Code 91108 is a standard zip code serving San Marino, San Marino, California (CA), in Los Angeles County, United States. It has an estimated population of 13,361 with a median household income of $140,703. The area falls within the America/Los_Angeles timezone.

Median Household Income vs. National Average

Location

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

Coordinates

Latitude: 34.120700
Longitude: -118.111700

Geographic Details

Land Area: 3.81 mi²
Water Area: 0.01 mi²
Population Density: 3505.0 people per mi² (90th percentile)
Bounding Box: 34.137360°N, 34.104976°S, -118.087946°E, -118.142213°W

With 13,361 residents spread across 3.81 square miles, this area has a population density of 3505.0 people per square mile.

Demographics

13,361

Population

70th percentile

$140,703

Median Income

95th percentile

$1,000,001

Median Home Value

95th percentile

3.81 mi²

Land Area

The median household income in 91108 is $140,703, and the median home value is $1,000,001. This places the area in the top 25% nationally for household income.

Housing

4,562

Total Units

4,415

Occupied Units

96.8%

Occupancy Rate

Nearby ZIP Codes

Other zip codes in San Marino, CA.

91118

San Marino

Similar ZIP Codes in California

ZIP codes with similar median household income in California.

94028

Portola Valley

$161,205

94301

Palo Alto

$122,473

94062

Redwood City

$125,060

94707

Berkeley

$138,144

94583

San Ramon

$119,623

94708

Berkeley

$140,611

94065

Redwood City

$132,337

95138

San Jose

$143,261

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.