Data as of October 18, 2026 · refreshed automatically from the official California voter file
Solano County, CA has 275,844 active registered voters — 23.6% Republican, 46.8% Democratic, and 22.2% with no party affiliation, as of October 2026.
Party registration
Most reliable-voting precincts
| # | Precinct | Active voters | Supervoters | Supervoter % |
|---|---|---|---|---|
| 1 | 54020.00 | 803 | 650 | 80.95% |
| 2 | 54021.00 | 535 | 433 | 80.93% |
| 3 | 54025.00 | 983 | 794 | 80.77% |
| 4 | 54026.00 | 534 | 431 | 80.71% |
| 5 | 54023.00 | 830 | 656 | 79.04% |
| 6 | 53140.00 | 784 | 613 | 78.19% |
| 7 | 56030.00 | 456 | 352 | 77.19% |
| 8 | 21005.00 | 798 | 585 | 73.31% |
| 9 | 56015.00 | 712 | 521 | 73.17% |
| 10 | 56017.00 | 454 | 330 | 72.69% |
Supervoters are active registered voters who cast a ballot in at least 3 of the last 4 November general elections (2018–2024). Percentages are precinct totals from the official state voter file — no individual voter information is shown. Precincts with fewer than 400 active voters are excluded.
How Solano County voted for president
Election results are public records.
Solano County at a glance.
Solano County had an estimated 455,101 residents in July 2024, the 19th most populous of California's 58 counties, up 0.3% since the 2020 census. Of those, 357,585 are 18 or older, the voting-age population, and 18.4% are 65 or older. Its 275,844 active registered voters equal about 77.1% of that voting-age population.
It covers 822 square miles of land (554 people per square mile), and 4.0% of residents live outside any incorporated city or town. The largest cities and towns are Vallejo (123,475), Fairfield (122,646), Vacaville (103,994), Suisun City (29,614) and Benicia (26,477). The American Community Survey (2020-2024) puts it at a median age of 39.2, a median household income of $100,401, 28.8% of adults 25 and older holding a bachelor's degree or higher and 63.0% of occupied homes owned by the people living in them.
In 2024, 189,834 votes were cast for president, about 53.1% of the voting-age population; the Democratic ticket took 60.1% and the Republican ticket 37.1%. The two-party margin moved from D+28.6 in 2008 to D+23.0 in 2024.
- Population (2024 estimate)
- 455,101
- Population (2020 census base)
- 453,551
- Voting-age population (18+)
- 357,585
- Active voters per 100 adults
- 77.1
- Residents 65 and older
- 18.4%
- People per square mile
- 554
- Living outside incorporated places
- 4.0%
- Land area
- 822 sq mi
- Median age
- 39.2
- Median household income
- $100,401
- Adults 25+ with a bachelor's degree
- 28.8%
- Owner-occupied homes
- 63.0%
Largest cities and towns
- Vallejo 123,475
- Fairfield 122,646
- Vacaville 103,994
- Suisun City 29,614
- Benicia 26,477
Presidential vote, 2008–2024
| Year | Democratic | Republican | Margin | Votes cast |
|---|---|---|---|---|
| 2024 | 60.1% | 37.1% | D+23.0 | 189,834 |
| 2020 | 64.0% | 33.7% | D+30.3 | 205,831 |
| 2016 | 62.3% | 31.8% | D+30.5 | 156,067 |
| 2012 | 62.9% | 34.9% | D+28.0 | 138,565 |
| 2008 | 63.4% | 34.8% | D+28.6 | 160,973 |
Sources: U.S. Census Bureau Vintage 2024 population estimates and 2024 Gazetteer; American Community Survey 2020–2024 5-year estimates; certified county presidential returns. Growth, density and turnout are simple arithmetic on those figures.
Running in Solano County?
The voter file is loaded. Create your campaign and start canvassing in minutes.
Start free in Solano CountyAlso see: Motion51 in California · Pricing