What is the main zip code for Palo Alto, California?

94303 is the most populous Palo Alto ZIP code in Census data with about 47,989 residents.

What is the area code for Palo Alto, California?

Palo Alto, California uses area code 650.

What time zone is Palo Alto, California in?

Palo Alto, California is in the Pacific Time Zone.

Palo Alto, California Zip Codes

Q: How many zip codes does Palo Alto, California have?

Palo Alto, California has 9 zip codes in this directory: 4 standard delivery ZIPs and 5 PO Box or unique ZIPs.

Q: What county is Palo Alto, California in?

Palo Alto is in Santa Clara County, California.

📍 Palo Alto is in Santa Clara County, California with 9 zip codes; the most populous is 94303.

City

Palo Alto

County

Santa Clara

Zip Codes

Area Code

650

Palo Alto is a USPS city name in Santa Clara County, California with a Census population of approximately 97,522 across its ZIP codes. Santa Clara County as a whole has 115 ZIP codes in this directory. Below you'll find every zip code serving Palo Alto with population, income and home value, a map, and the city's affordability profile.

Population and demographic data sourced from the U.S. Census Bureau American Community Survey (ACS) 5-Year Estimates. ZIP code routing data sourced from the United States Postal Service (USPS).

All Palo Alto Zip Codes

ZIP Code	City	County	Population	Median Income	Median Home	Details
94301	Palo Alto	Santa Clara	17,259	$217,611	$2,000,001	View →
94302	Palo Alto	PO Box ZIP	—	—	—	View →
94303	Palo Alto	Santa Clara	47,989	$144,259	$1,670,900	View →
94304	Palo Alto	Santa Clara	4,489	$159,637	$2,000,001	View →
94306	Palo Alto	Santa Clara	27,785	$199,800	$2,000,001	View →
94307	Palo Alto	PO Box ZIP	—	—	—	View →
94308	Palo Alto	PO Box ZIP	—	—	—	View →
94309	Palo Alto	PO Box ZIP	—	—	—	View →
94310	Palo Alto	PO Box ZIP	—	—	—	View →

Palo Alto at a Glance

Residents (ZIPs with data)

97,522

Median household income

$179,719

Median home value

$2,000,000+

Price-to-income ratio

10.8

Median rent

$2,907

Owner-occupied

55%

Bachelor's degree+

81%

Poverty rate

6.6%

Palo Alto has 9 ZIP codes in this directory: 4 standard delivery ZIPs and 5 PO Box or unique ZIPs that carry no resident population in Census data. The 4 ZIPs with published Census housing data cover 97,522 residents, the largest being 94303 with 47,989 people.

The median ZIP in Palo Alto has a household income of $179,719 and a home value of more than $2,000,000, a price-to-income ratio of at least 10.8, far above the 6.7 California ZIP median. The highest median income is in 94301 at $217,611. Median rent across these ZIPs is $2,907 a month.

55% of households in the typical Palo Alto ZIP own their home (statewide ZIP median 64%). 81% of adults hold a bachelor's degree, far above the 31% statewide median. The median poverty rate is 6.6%, below the 10.8% statewide ZIP median. Overall density is about 4,950 residents per square mile across 20 square miles of ZIP land area.

Medians are taken across the ZIP codes listed below (each ZIP weighted equally); PO Box and no-data ZIPs are excluded. Definitions on the methodology page; statewide comparisons in the 2026 California ZIP Code Affordability Report.