California voters have rejected Proposition 40, a one-time 5% tax on the state’s billionaires, with 52.8% voting against the measure and 47.2% in favour. The Associated Press called the result on Monday, 9 November 2026, six days after voters cast their ballots on Tuesday, 3 November, because California counts its mostly mail-in ballots over several days.
The defeat closes the most expensive ballot-measure fight of the 2026 election cycle and hands a rare loss to the progressive wing of the Democratic Party in the same election that gave Democrats control of both chambers of Congress. About 83% of ballots had been counted when the AP determined the “no” lead — roughly 5.91 million votes against and 5.29 million in favour — could not be overturned.
What Proposition 40 would have done
Proposition 40, formally titled the One-Time Wealth Tax for State-Funded Health Care Programs Initiative, would have imposed a one-time 5% tax on the net worth of California residents worth more than $1 billion as of 1 January 2026. It would have applied to roughly 200 billionaires living in the state, including some of the richest people in the world.
Supporters, led by the healthcare workers’ union SEIU-United Healthcare Workers West, projected the tax would raise about $100 billion. Most of that money would have backfilled federal healthcare funding cuts, with 10% directed to education and food-assistance programmes. The union argued the money was needed to replace an estimated $100 billion California stands to lose in federal healthcare funding over five years, a shortfall that threatens Medi-Cal, the state’s healthcare programme for low-income residents.
The measure was designed by economists Gabriel Zucman and Emmanuel Saez, whose work on taxing extreme wealth has shaped progressive tax debates in the United States and Europe. It qualified for the ballot in June with 980,438 valid signatures.
A $378 million campaign, and a 10-to-1 spending gap
Opponents spent about $378.4 million to defeat the measure, according to CalMatters, while supporters of the tax raised $33.5 million. Google co-founder Sergey Brin alone gave $102 million to Building a Better California, the political action committee he founded to fight the tax. CNN reported that Brin funnelled just over $100 million to the group trying to defeat the tax.
| Proposition 40 at a glance | Detail |
|---|---|
| Result | Rejected — 52.8% No, 47.2% Yes |
| Votes counted | About 83% when AP called it |
| Votes against | About 5,909,778 |
| Votes in favour | About 5,288,379 |
| Called by | Associated Press, Monday 9 November 2026 |
| Opposition spending | About $378.4 million |
| Supporters’ fundraising | $33.5 million |
| Largest single donor against | Sergey Brin, $102 million |
Critics of the tax argued it would drive ultrawealthy residents out of California, taking billions of dollars in income tax revenue with them. Brin himself publicly moved out of the state during the campaign. Supporters countered that the tax was a one-time levy on wealth already accumulated in California, and that the state could not afford to lose the healthcare funding it was designed to replace.
Why Democrats split over their own tax
The most striking feature of the result is how it divided California Democrats. Outgoing Governor Gavin Newsom opposed the measure, as did Xavier Becerra, the Democrat elected governor on the same ballot. Both warned the tax could push entrepreneurs and wealthy residents out of the state.
Supporters included Senator Bernie Sanders of Vermont and Representative Ro Khanna of California, along with the California Democratic Party and the California Federation of Labor Unions. Newsom, who is widely seen as a possible candidate for the 2028 Democratic presidential nomination, instead proposed a national tax on billionaires.
The split showed up in the voting. An AP Voter Poll found that a majority of California voters under 30 backed the tax, while roughly seven in 10 voters aged 65 and older voted against it. A separate UC Berkeley Citrin-POLITICO poll found 45% of voters favoured taxing billionaires more to fund public services, against 35% who preferred keeping billionaires in the state for their taxes and jobs — yet only 46% supported Proposition 40 itself, suggesting many voters liked the idea in principle but not this measure.
That tension is part of a wider post-midterm picture. In his first television interview since the elections, Trump told CBS’s 60 Minutes that his immigration crackdown may have cost Republicans votes, a reminder that both parties are still working out what voters punished and rewarded on 3 November. California’s rejection of the billionaire tax, on the same night Democrats swept Congress, is the clearest sign yet that the electorate’s mood does not fit neatly into either party’s story.
The same week, Wall Street delivered its own verdict on the post-election mood, with the Dow Jones surging more than 1,100 points on Monday.
What happens next
Two companion measures were also on the ballot. Proposition 42, backed by Brin, would ban retroactive wealth taxes and was leading with 51.6% of the vote on Monday evening, although the Associated Press had not called it. Proposition 41, which would have required the state auditor to examine new special tax proposals before they reach the ballot, was rejected, with 54.8% voting no.
Supporters of the billionaire tax have said they could put the measure back on the ballot in 2028. If Proposition 42 passes, however, it would make a repeat attempt far harder, since it would bar the kind of retroactive tax Proposition 40 proposed. The final count is still to be certified by the California Secretary of State on 11 December.
For now, the result stands as a limit on how far even California — the most Democratic-leaning large state in the country — is willing to go on taxing wealth. The debate over billionaire taxes is likely to follow Newsom and other potential 2028 contenders into the presidential race, but after Monday’s result, its supporters will have to answer the question the campaign never settled: how to tax extreme wealth without losing the people who hold it.
Frequently asked questions
What was California Proposition 40?
Proposition 40 was a ballot measure that would have imposed a one-time 5% tax on the net worth of California residents worth more than $1 billion as of 1 January 2026. It was formally titled the One-Time Wealth Tax for State-Funded Health Care Programs Initiative.
Did Proposition 40 pass?
No. California voters rejected it, with 52.8% voting no and 47.2% voting yes. The Associated Press called the result on Monday, 9 November 2026, with about 83% of ballots counted.
How much money would Proposition 40 have raised?
Supporters projected about $100 billion, with most of it earmarked to backfill federal healthcare funding cuts and 10% directed to education and food-assistance programmes.
Who opposed Proposition 40?
Opponents included Governor Gavin Newsom and Governor-elect Xavier Becerra, both Democrats, along with a campaign funded largely by wealthy tech figures. Google co-founder Sergey Brin gave $102 million to the committee fighting the measure, and opponents spent about $378.4 million in total.
Could the billionaire tax come back?
Supporters have said they could try again in 2028, but Proposition 42, which was leading on Monday evening, would ban retroactive wealth taxes if it passes, making a repeat attempt much harder.
