California ballot measure · November 3, 2026

California Proposition 40, explained

One-time tax on billionaires' wealth. A ballot measure is a yes-or-no question put directly to voters — no candidate is involved, and the wording on the ballot is the wording that becomes law. This page shows that wording first, then what it actually changes.

The official wording

IMPOSES ONE-TIME TAX ON CERTAIN TAXPAYERS. INITIATIVE CONSTITUTIONAL AMENDMENT AND STATUTE. Imposes 5% tax on certain taxpayers with assets over $1 billion; revenue primarily for health care. Exempts revenues from constitutional requirements for school funding and spending limit. Fiscal Impact: Temporary revenue increase of tens of billions of dollars spread over several years from wealth tax on billionaires. Possible ongoing decrease of less than $1 billion per year in income tax revenue from billionaires.

This is what appears on the ballot. Everything below explains it.

What it actually means

Imposes a one-time state tax equal to 5% of net worth on people and trusts worth more than $1 billion who lived in California on January 1, 2026. The tax would be due in 2027. Ninety percent of the money must go to health care and the rest to education, food assistance and running the tax.

If you vote YES

California billionaires who were residents on January 1, 2026 would owe a one-time tax of 5% of net worth in 2027, with the option to pay over five years at extra cost; real estate, pensions and retirement accounts would generally be excluded.
The state would probably collect tens of billions of dollars spread over several years.
90% of the money would have to be spent on health care services and could not replace existing funding; the rest would go to education, food assistance and administration.
The money would not count toward the constitutional school funding guarantee, budget reserve rules or the state spending limit.
State income tax revenue could fall by less than $1 billion a year if some billionaires leave or change how they receive income.

If you vote NO

California would continue to tax billionaires' income, but not their wealth; there is no state tax on simply owning stocks or other financial assets.
Health care, education and food assistance would be funded through the regular state budget, without a dedicated one-time source.

The numbers that matter

One-time revenue: Probably tens of billions of dollars over several years
Possible ongoing income tax loss: Less than $1 billion a year
Administration cost: Possibly tens of millions of dollars a year for several years, paid from tax revenue

Why supporters say YES

Federal cuts have reduced health care funding for Californians; a one-time 5% tax on about 200 billionaires who together hold $2 trillion would keep hospitals open and coverage affordable.
— Official argument in favor, signed by SEIU-United Healthcare Workers West, a Planned Parenthood of Pacific Southwest employee and a member of AFT Local 1521
The tax cannot be applied to anyone other than billionaires, who pay much lower effective tax rates than working families, and opponents have offered no other plan to replace lost health care funding.
— Official rebuttal, signed by SEIU-United Healthcare Workers West, a Planned Parenthood of Pacific Southwest employee and a member of AFT Local 1521

Why opponents say NO

A one-time tax provides only temporary money; a Stanford economists' study estimated it would cost California $25 billion in lost revenue as companies and wealthy residents move out of state.
— Official argument against, signed by the California Medical Association, the California Primary Care Association and the California School Boards Association
Exempting the revenue from the school funding guarantee shortchanges schools about $3 billion a year, and the measure lets the Legislature amend it without another vote, which opponents say could open the door to broader wealth taxes.
— Official rebuttal to the argument in favor, signed by a California Teachers Association teacher, the California Taxpayers Association and the State Building and Construction Trades Council of California

What’s genuinely uncertain

Propositions 41 and 42 on the same ballot each say that conflicting measures are void if they receive more yes votes. The Legislative Analyst warns that if either gets more yes votes than Proposition 40, courts could find a conflict and Proposition 40 might not take effect even if it passes.
How much is collected, and when, is very hard to predict: much billionaire wealth is in stock whose value changes, and taxpayers may act to reduce what they owe.
The $100 billion revenue figure in the supporters' argument and the $25 billion loss figure in the opponents' argument come from the campaigns and outside studies, not the Legislative Analyst.
Governor Gavin Newsom and both major-party candidates for governor oppose the measure, according to the official argument against.

The bottom line

A large one-time sum for health care paid by a few hundred billionaires, against the risk that some leave, ongoing income tax revenue falls and schools get no share under the funding guarantee.

One neutral sentence describing the tradeoff — not a recommendation.

Sources:vig.cdn.sos.ca.gov ballotpedia.org

Checking it against the official text

The California Secretary of State publishes the certified measures and, in most states, an official voter guide with fiscal notes. That is the authoritative version. Everything here is an explanation of it, not a substitute for it.

Confirm this with the official source

Your ballot is determined by your election authority, not by us. Verify your registration, precinct, and sample ballot at California Secretary of State.

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