“Imposing a wealth tax at the state level causes billionaires to relocate to other states.” — Gavin Newsom. Our verdict: Unverified.
Gavin Newsom made the claim while explaining his opposition to California's Billionaire Tax Act, as reported by KQED on 27 October 2026.
Our verdict
Unverified
We could not confirm or refute the claim that a state wealth tax causes billionaires to move to other states. No US state has ever brought in such a tax, so there is no real-world evidence of what happens afterwards — only projections and political argument.
Know something that settles it? Send us evidenceWhat we found
Gavin Newsom did say that a state wealth tax would push billionaires to relocate. KQED reported his remarks on 27 October 2026, and that part is not in doubt. What we cannot check is the causal claim itself: that imposing the tax actually causes billionaires to leave.
The material we found looks forward rather than back. The Tax Foundation notes that California's proposed wealth tax includes measures meant to stop taxpayers moving away — a sign the state expects relocation to be a risk, but not proof that it happens. A California Tax Foundation study reported by CalTax estimates the tax would cost the state more than $3.5 billion a year and points to nine billionaires who had already left, though it does not show the tax caused those departures.
Because no state has enacted a wealth tax on billionaires, there is no observed migration data to weigh. The case for the claim rests on simulations and projections; the case against it has not been tested in practice either. We therefore could not find enough public evidence to confirm or refute the claim. If you have evidence either way, please send it to us.
The evidence
2 of 4 sources support the claim; none contradict it.
- Background
KQED reported that Gavin Newsom said a state-level wealth tax would cause billionaires to relocate to other states. [1]
- Supports the claim
The Tax Foundation notes that California's proposed wealth tax includes provisions aimed at taxpayer relocation, suggesting the state expects some risk of taxpayers leaving to avoid the tax. [2]
- Supports the claim
A California Tax Foundation study reported by CalTax estimates the proposed wealth tax would lead to billionaire departures and more than $3.5 billion in lost annual revenue, citing nine previously identified billionaire departures. [3]
- Background
A Substack post on the research behind the Billionaire Tax Act notes that Gavin Newsom has publicly opposed the proposal. [4]
What we could not confirm
- Whether billionaires actually move after a state enacts a wealth tax, since no US state has done so and no observed migration data exists.
- Whether the nine billionaire departures cited in the California Tax Foundation study were caused by the proposed tax or by other factors.
- Whether the effect would be the same in states outside California, or over the long term.
How we checked
We looked at the original KQED report of Newsom's remarks, at policy and legal analyses of California's proposed wealth tax, and at a study of its projected revenue effects. We searched for real-world migration data after a state wealth tax was enacted, but found none, because no state has passed one. We reviewed 4 relevant sources.
Sources
- [1]www.kqed.org · The Political Calculus Behind Newsom’s Opposition to California’s Billionaire Tax | KQED · October 27, 2026
- [2]taxfoundation.org · Constitutional Flaws of California’s Proposed Wealth Tax
- [3]caltax.org · Wealth Tax Would Cost State More Than $3.5 Billion in Ongoing Annual Revenue, Study Finds - CalTax · April 22, 2026
- [4]ncpipeline.substack.com · The research driving the Billionaire Tax Act debate
- [5]Photo: Office of the Lieutenant Governor of California / Wikimedia Commons, Public domain
Help us check this claim
We could not find enough public evidence to confirm or refute this claim. If you know of an official record, dataset, transcript or report that settles it, send us the link. We review every submission and update this fact check when the evidence changes the picture.
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