2024 presidential election
San Mateo
HarrisD+52.3
Constituent county margins for San Mateo, CAOne cell per constituent county, colored by 2024 presidential margin from deep red (Republican) through neutral to deep blue (Democratic), ordered bluest first.
How it voted
Share of the 2024 vote
| Kamala Harris ✓Democratic | 74.6% | 33,553 |
|---|---|---|
| Donald TrumpRepublican | 22.2% | 10,005 |
| OtherAll other candidates | 3.2% | 1,447 |
D+60R+60
1 counties, each filled by 2024 D-vs-R margin.
presidential history
Presidential margin, 2008–2024
Democratic minus Republican, by election
| Year | Margin (D minus R) |
|---|---|
| 2008 | +46.6% |
| 2012 | +47.8% |
| 2016 | +57.2% |
| 2020 | +57.8% |
| 2024 | +52.3% |
DemocraticRepublican
5 presidential elections
| Year | Won | Margin | Democratic | Republican | Total |
|---|---|---|---|---|---|
| D | 33,553 | 10,005 | 45,005 | ||
| D | 39,303 | 10,179 | 50,419 | ||
| D | 32,917 | 8,202 | 43,209 | ||
| D | 28,043 | 9,897 | 37,940 | ||
| D | 27,883 | 10,121 | 38,117 |
Demographics
Demographic profile
Demographic Profile
Key indicators compared across containing geographies
| Indicator | San MateoCity | CaliforniaState | United StatesNation |
|---|---|---|---|
| Race & Ethnicity | |||
| White | 37.9% | 39.7% | 61.0% |
| Black | 1.4% | 5.4% | 12.2% |
| Asian | 28.3% | 15.5% | 6.0% |
| Two or more races | 15.9% | 19.2% | 12.6% |
| Other race | 15.0% | 20.1% | 8.2% |
| Hispanic or Latino | 27.6% | 40.1% | 19.3% |
| Income & Age | |||
| Median household income | $153,504 | $99,122 | $84,427 |
| Poverty rate | 8.2% | 12.0% | 12.5% |
| Median age | 38.3 | 37.9 | 39.1 |
| Age 18–24 | 7.3% | 9.1% | 9.2% |
| Age 65 and older | 17.7% | 15.6% | 17.2% |
| Education & Language | |||
| Bachelor's degree or higher (25+) | 57.8% | 37.1% | 35.7% |
| Speaks a non-English language at home | 46.6% | 44.4% | 22.3% |
| Spanish | 20.5% | 28.3% | 13.6% |
| Chinese (incl. Mandarin & Cantonese) | 9.4% | 3.5% | 1.1% |
| Other Indo-European | 5.6% | 3.5% | 2.0% |
| Other Asian & Pacific Island | 3.2% | 2.0% | 1.1% |
| Ancestry | |||
| Largest ancestry | Irish 6.6% | German 6.8% | German 12.5% |
| 2nd-largest ancestry | German 6.0% | English 6.3% | English 9.5% |
| 3rd-largest ancestry | English 6.0% | Irish 5.9% | Irish 9.4% |
| Religion | |||
| Catholic | 21.1%County context | 26.2% | 18.6% |
| Evangelical Protestant | 3.5%County context | 9.0% | 16.5% |
| Unaffiliated or unclaimed | 66.6%County context | 55.2% | 51.5% |
ACS values are survey estimates and may include margins of error.
Religion data may be available only at county or larger geographies. Sub-county values are labeled when inherited, modeled, or contextual.
2024 ACS
Race, ethnicity, and ancestry
Click any group to see the ancestries typically reported within it.
Irish
6.6%
German
6.0%
English
6.0%
Italian
5.0%
American
2.8%
French
1.7%
Scottish
1.3%
Source · American Community Survey 5-year estimates, 2024 release. Hispanic/Latino is an ethnicity that overlaps the race categories, so these shares can total more than 100%. Ancestry is a self-reported, multiple-response item; ancestry percentages do not sum to the parent race percentage.
2024 ACS
Age distribution by sex
Median age: 38.3 in this county, 39.1 nationally
Male
Age
Female
85+
75–84
65–74
55–64
45–54
35–44
25–34
18–24
5–17
<5
Source · American Community Survey 5-year estimates, 2024 release.
2024 ACS
Median household income
Inflation-adjusted dollars
$153,504
San Mateo$153,504
California$99,122
United States$80,734
Source · American Community Survey 5-year estimates, 2024 release.
2024 ACS
Poverty rate
All persons below federal poverty line
8.2%
Child poverty is below the national average.
Children under 186.2%
Working age (18–64)6.4%
Seniors (65+)10.7%
Source · American Community Survey 5-year estimates, 2024 release.
2024 ACS
Language at home
Population aged 5 and older
53.4%
speak English only
Spanish20.5%
Chinese (incl. Mandarin & Cantonese)9.4%
Other Indo-European5.6%
Other Asian & Pacific Island3.2%
Tagalog (incl. Filipino)2.9%
Russian, Polish, or other Slavic1.5%
French (incl. Cajun & Haitian)1.0%
Korean0.7%
Arabic0.7%
German or other West Germanic0.4%
Other languages0.3%
Vietnamese0.2%
Source · ACS 5-year estimates, 2024.
2020 religion census
Religious adherents
Adherents per capita by tradition
Unaffiliated or not counted66.6%
Source · 2020 US Religion Census. The unaffiliated-or-not-counted share is everyone not claimed as an adherent by any reporting body — uncounted congregations as well as the religiously unaffiliated.
San Mateo sits in the Pacific Coast. In 2024 it voted Democratic.
Across the recorded series it reached a Democratic high of 57.8 points in 2020. Between 2020 and 2024 the city moved 5.4 points toward the Republican candidate; the 2024 margin was 52.3 points.
A population of 103,105, a 38% non-Hispanic-white share, and a median household income of $153,504 describe the city.
Compare two places, side by side
Twelve curated comparisons line up election history, demographics, and the divergence story for two places at a glance. Browse all comparisons →
Cite this page
All citations released under CC BY 4.0. Attribution: Akashic Intelligence.
San Mateo, California. Akashic. https://akashic.app/city/0668252/. Accessed May 20, 2026. License: CC BY 4.0.
License: CC BY 4.0
Frequently asked questions
How did San Mateo, California vote in 2024?
In 2024, San Mateo, California voted Democratic by 52.3 points (D+52.3), carried by the Democratic candidate. Out of 45,005 votes cast, 33,553 went Democratic and 10,005 went Republican.
What is San Mateo, California's political typology?
Akashic places San Mateo, California in the "" typology. The typology is a data-driven cluster built from vote share, vote swing, race and ethnicity, income, language spoken at home, religion, and ancestry. Across 5 elections in the dataset, the city has voted Democratic 5 times, Republican 0 times, and other 0 times.
How many people live in San Mateo, California?
San Mateo, California has a population of 103,105 according to the 2024 American Community Survey 5-year estimates from the US Census Bureau.
What is the median household income in San Mateo, California?
Median household income in San Mateo, California is $153,504 — above the national median of $80,734. The California state median is $99,122.
What is the political history of San Mateo, California?
Akashic tracks 5 presidential elections in San Mateo, California from 2008 to 2024. Of those, 5 went Democratic and 0 went Republican. The city's typology — "" — captures where that record, its demographics, and its recent swing place it among American communities.