Summary: Prop 40 would impose a one-time 5% tax on billionaires who lived in California on January 1, 2026, putting the measure before voters within weeks.
California voters are preparing to decide a closely debated ballot measure that could create a significant tax obligation for the state’s wealthiest residents. Known as Prop 40, the proposal would apply a one-time 5% tax to billionaires who lived in California as of January 1, 2026.
What Prop 40 would do
The measure is designed as a single tax rather than a recurring annual charge. Its eligibility would be tied to residency on a specific date, making January 1, 2026, central to determining which billionaires fall within the proposal’s scope.
The measure does not apply broadly to all residents. Instead, it focuses on people identified as the state’s billionaires and would require the tax only once.
Why the vote matters
Prop 40 has become the subject of substantial debate ahead of the vote. Its outcome could determine whether California proceeds with a one-time levy aimed at its billionaire population.
For affected residents, the proposal places the timing of residency and the size of the proposed tax at the center of the issue. For voters, the measure presents a direct decision on whether California should adopt this approach to taxing billionaire wealth.
Californians are expected to vote on Prop 40 in the coming weeks.