San Mateo County is a county of 742,340 people in California. The typical home is worth $1,559,600, having roughly tripled since 2000. Households here earn about 60% more than in California as a whole. The foreign-born share is 36%. The median household earns $158,855, about 93% above the national median. Median rent is $2,922 a month.
At a glance
Wealthier
median household income $158,855, above the US median
US median: $82,259
Mid-age
median age 40.9
US median: 38.9
More educated
54% hold a bachelor's degree
US average: 36%
Less affordable
home values up 90%, inflation adjusted
US median home: $376,019
Unique to this place
What stands out about San Mateo County
What changed most since 1990
Asian share16.3% → 31.0%(+14.7 pts)US over the same years: +3.1 pts
White share60.6% → 34.7%(−25.9 pts)US over the same years: −17.8 pts
Adults with a bachelor's degree31.3% → 53.7%(+22.3 pts)US over the same years: +15.3 pts
Shares are "alone or in combination": a person with both Medicare and Medicaid counts in each, so categories overlap and do not sum to 100%.
Section 09 · Service history
Veterans
Veterans by period of service, 2024
Gulf War (2001 or later)17.6%(3,060)
US avg: 26.4%
Gulf War (1990s)14.5%(2,523)
US avg: 24.3%
Vietnam era37.6%(6,539)
US avg: 33.1%
Korean War9.9%(1,722)
US avg: 4.5%
World War II2.1%(359)
US avg: 1%
Share of the 17,374 veterans here. A veteran who served across eras counts in each, so shares can total more than 100%. Peacetime-only service is included in the total but not shown as an era.
BAR + DOT: THIS PLACE · TICK: US AVERAGE
Over time
San Mateo County, decade by decade
San Mateo County population, inflation-adjusted income and home value, education, and diversity by year
Year
Population
Median household income
Median home value
Bachelor's degree+
Diversity score
1990
649,623
$111,452
$817,943
31.3%
71.7
2000
707,161
$129,008
$819,563
39.0%
82.6
2010
718,451
$123,211
$1,128,990
44.0%
86.7
2020
764,442
$155,251
$1,409,722
52.1%
89.3
2024
742,340
$158,855
$1,559,600
53.7%
89.4
Census years come from the decennial census and the latest year from the American Community Survey, so part of any change between those two rows can reflect the different surveys. Dollar figures are adjusted for inflation to 2024 dollars; a figure ending in "+" was at the Census Bureau's reporting cap that year. The diversity score runs from 0 to 100; see how it's calculated.
How many people live in San Mateo County, California?
San Mateo County, California has about 742,340 residents according to the 2024 American Community Survey.
What is the median household income in San Mateo County, California?
The typical household in San Mateo County, California earns about $158,855 a year. Half of households make more than that, and half make less.
Is San Mateo County, California expensive?
In San Mateo County, California, the median home is worth about $1,559,600, and the typical rent is about $2,922 a month.
How educated are people in San Mateo County, California?
About 53.7% of adults age 25 and over in San Mateo County, California hold a bachelor's degree or higher.
What is the poverty rate in San Mateo County, California?
About 6.7% of people in San Mateo County, California live below the federal poverty line.
Has San Mateo County, California grown since 1990?
Yes, San Mateo County, California has grown since 1990. The population has added about 92,717 residents, a change of about 14 percent over that period.