California · Ballot measure
Proposition 40: One-time tax on billionaires
On the ballot: November 3, 2026 Initiative constitutional amendment and statute
A YES vote means
Billionaires who lived in California on January 1, 2026 would pay a one-time state tax equal to 5% of their net worth, due in 2027 (payable over five years at extra cost).
A NO vote means
The state would not collect this one-time tax.
Who supports it
- SEIU-United Healthcare Workers West
Who opposes it
- California Medical Association
- California Primary Care Association
- California School Boards Association
- California Taxpayers Association
- State Building and Construction Trades Council of California
From official campaign filings and public endorsements, each linked on the full page (checked October 30, 2026). Not complete; not an endorsement.