† Citizen voting-age population estimated for prior cycles; 2004 predates the ACS and is extrapolated. Source: ACS 5-year, table B05003.
——
D+60R+60
20042024
Boundary by 2024 margin · Precinct returns · VEST · MIT Election Lab
People and households
Who lives here
Exact values for this place, its state, and the United States.
Race · ethnicity · ancestry
Communities and origins
GroupAltadenaCaliforniaUnited States
German7.5%6.8%12.5%
Irish6.6%5.9%9.4%
English6.6%6.3%9.5%
American5.4%2.8%5.3%
Italian4.4%3.4%4.8%
Armenian3.5%——
Polish1.9%0.9%2.2%
French1.7%1.3%1.6%
Mexican19.5%32.3%11.3%
Salvadoran2.5%2.0%0.7%
Guatemalan1.7%1.3%0.5%
Honduran0.3%—0.3%
Puerto Rican0.3%0.6%1.8%
Cuban0.2%—0.7%
Nicaraguan0.2%0.3%—
Colombian0.2%0.3%0.4%
African American†15.1%4.4%9.9%
African0.9%0.3%0.5%
Nigerian0.5%—0.2%
Jamaican0.5%—0.4%
Chinese1.9%3.9%1.3%
Filipino1.5%3.3%0.9%
Korean0.9%1.2%0.4%
Asian Indian0.4%2.3%1.4%
Vietnamese0.4%1.7%0.6%
Japanese0.4%0.6%0.2%
Taiwanese0.2%0.3%—
Aztec7.1%0.3%—
Maya4.2%——
Samoan1.4%——
Hispanic or Latino counts residents of any race; the race groups count only their non-Hispanic residents, so the groups are mutually exclusive and sum to 100%. Expand a row to see ancestries reported within that group.
Age and life stage
Measure
Altadena
California
United States
Median age
46.4
37.9
39.1
Age 18–24
5.6%
9.1%
9.2%
Age 65 and older
21.9%
15.6%
17.2%
Household economy
Measure
Altadena
California
United States
Median household income
$128,720
$99,122
$84,427
Poverty rate
7.9%
12.0%
12.5%
Bachelor's degree or higher (25+)
53.3%
36.6%
35.6%
Languages at home
Measure
Altadena
California
United States
Speaks a non-English language at home
34.1%
44.4%
22.3%
Spanish
21.3%
28.4%
13.6%
Other Indo-European
6.7%
3.4%
2.0%
Chinese (incl. Mandarin & Cantonese)
1.7%
3.5%
1.1%
Religious landscape
Measure
Altadena
California
United States
Catholic
—
26.2%
18.6%
Evangelical Protestant
—
9.0%
16.5%
Unclaimed / not counted
—
55.2%
51.5%
American Community Survey 2024 5-year (CVAP, income, age, poverty, education, language, race, ancestry) · presidential returns from MIT Election Lab through 2024 · 2020 U.S. Religion Census (ASARB) — congregational adherents; unclaimed is the residual not counted by congregations.
Altadena, California
presidential history
Presidential margin, 2004–2024
Democratic minus Republican, by election
Presidential margin over time
Year
Margin (D minus R)
2004
+49.7%
2008
+60.2%
2012
+57.3%
2016
+61.2%
2020
+61.3%
2024
+58.3%
DemocraticRepublican
6 presidential elections
Third column names the leading third-party or independent finisher. Source · MIT Election Lab · ICPSR · VEST (precinct-level 2024). Swing · margin change from the prior cycle. vs U.S. · margin relative to the national result that year. Third-party votes in 2012 are allocated from certified county totals by this place's share of each county's two-party vote — that cycle's precinct source records two-party splits. † 2004, 2012, 2024 sub-county results are estimated: the source's block-level detail for these cycles was unreliable — either county/municipality-level consolidated reporting (COVID-era) or a precinct-to-block allocation that misplaced votes — so the figures are allocated from the constituent county totals in proportion to the place and scaled to certified totals.
Year
Won
Democratic
Republican
Other
Margin
Swing
vs U.S.
Total
D
77.5%Harris18,801
19.2%Trump4,663
3.3%
D+58.3
R+3.0
D+59.7
24,261
D
79.7%Biden20,974
18.4%Trump4,836
1.9%
D+61.3
D+0.1
D+56.9
26,323
D
77.9%Clinton17,036
16.7%Trump3,653
5.5%
D+61.2
D+3.9
D+59.1
21,882
D
77.4%Obama16,708
20.1%Romney4,342
2.5%
D+57.3
R+2.9
D+53.4
21,585
D
80.0%Obama17,359
19.8%McCain4,299
0.2%
D+60.2
D+10.4
D+52.9
21,711
D
74.3%Kerry15,269
24.6%Bush5,056
1.0%
D+49.7
—
D+52.2
20,538
Altadena sits just north of Pasadena in the San Gabriel foothills as a census-designated place with no city government of its own, giving county-level races outsized local relevance. Its relatively high Black homeownership share distinguishes it demographically from surrounding communities.
Across the recorded series it reached a Democratic high of 61.3 points in 2020. Between 2020 and 2024 the city moved 3.0 points toward the Republican candidate; the 2024 margin was 58.3 points.
A population of 41,705, a 42% non-Hispanic-white share, and a median household income of $128,720 describe the city. The city's voting pattern over the last decade is most similar to that of Culver City and Santa Monica.
Akashic
Political twins — cities
The cities whose fingerprint — 2000–2024 trajectory, demographics, ancestry, religion — sits closest to this one, and why.
Twin score (0–100) = weighted cosine between tier-standardized fingerprints: presidential margins 2000–2024 with 12-yr trend and elasticity, ACS income, age, education, population and race, top reported ancestries, and religious adherence — chips name the closest-shared dimensions and the widest gap. Re-weight the groups in the twins explorer.
In 2024, Altadena, California voted Democratic by 58.3 points (D+58.3), carried by the Democratic candidate. Out of 24,261 votes cast, 18,801 went Democratic and 4,663 went Republican.
How many people live in Altadena, California?
Altadena, California has a population of 41,705 according to the 2024 American Community Survey 5-year estimates from the US Census Bureau.
What is the median household income in Altadena, California?
Median household income in Altadena, California is $128,720 — above the national median of $80,734. The California state median is $99,122.
What is the political history of Altadena, California?
Akashic tracks 6 presidential elections in Altadena, California from 2004 to 2024. Of those, 6 went Democratic and 0 went Republican.
