The 2026 Billionaire Tax: California’s Most Dangerous Fiscal Experiment Yet
California’s latest high-profile tax (ill conceived) idea is a proposed ballot initiative dubbed “The 2026 Billionaire Tax Act” (Initiative 25–0024).
Even though it’s not law (and isn’t even guaranteed to qualify for the ballot yet), it’s already influencing how some founders, investors, and advisors think about California as it applies to their investments and businesses.
It’s nearly impossible for business leaders to perform liquidity planning, entity structure, and valuation risk heading into spring of 2026. Here’s what to know.
What the initiative would do
If it qualifies and voters approve it in November 2026, the measure would impose a one-time 5% tax tied to the worldwide net worth of certain people who are California residents or part-year residents as of January 1, 2026, as well as certain trusts. That is, those that choose to stay, which is becoming a problem, namely those with wealth are increasingly choosing greener pastures like Texas, Tennessee, Nevada, Utah, Arizona, Florida, and well.….Just about anywhere other than high tax and spend California, New Jersey, and New York.
The hard part is valuation—especially private business equity
It’s nearly an impossible task and adds to the tax as it requires redirection of efforts and likely massive accounting bills. For billionaires whose wealth is mostly illiquid (e.g., private company stock, LLC interests, carried interests, layered holding structures), the most consequential issue is not the rate—it’s how “net worth” is determined and how disputes will be resolved. The initiative text and professional analyses flag that private business valuation becomes a major compliance and controversy driver. Great if you’re someone like me, a California tax attorney, however, for the public at large and those that don’t pull up roots and leave, a real nightmare.
Private-company rules can “pull” valuation upward
One key feature discussed by tax practitioners: the measure contemplates valuation approaches that can be influenced by recent financings or equity sales, which can create tension when a company’s last priced round is stale—or when a later round is a down-round and earlier valuations were higher. This is exactly the kind of interpretive gray area that tends to produce audit fights and litigation.
Founder control structures could matter
Another business-planning concern: when founders hold high-vote / multi-class structures, the measure’s approach can treat “control” as relevant in ways that may increase the presumed portion of enterprise value attributable to the founder, compared to pure economics. That can affect how companies think about governance and capitalization—especially late-stage private companies. Control and ownership generally greatly overlap, albeit when one must measure to what degree and produce a valuation, it moves from a relative objective to highly subjective exercise.
Public assets are comparatively straightforward
For publicly traded assets, valuation generally relies on market value on the relevant date—far simpler than private-company equity, where appraisals, methodology selection, and documentation become central. And while it may make litigation risk lower, it doesn’t remove the actual “one time” (who in their right mind would believe once a tax is put into place it will only be one time?) cost of the tax and the downward pressure it will place on valuations (some will have to sell for example just to pay the tax).
The “net worth” base is worldwide, with carveouts and traps
At a high level, the tax base is worldwide assets minus liabilities, but the details matter: there are exclusions (for example, certain retirement/pension-related items are described as excluded in policy summaries), and there are anti-avoidance/“lookback” style concepts that can make pre-year-end planning less intuitive than “sell it before 12/31.” Or in other words, it’s filled with problem solutions that attempt to solve the underlying problem.
A phase-out is built in
The measure includes a phase-out so it doesn’t fully apply below roughly $1.1 billion of net worth (with the threshold mechanics described in state and professional analyses).
How it becomes law (and why the Governor can’t veto it)
This is a citizen initiative statute route: proponents must collect enough valid signatures to reach the ballot, then win a statewide popular vote. If it passes, it becomes law without the Governor’s signature, meaning no veto. Much is said about how we live in a democracy, and this is a pure democracy action as it allows the general voting public to decide the issue. Another way to describe this method of deciding public policy is mob rule. There’s a very highly valid reason our founding fathers rejected democracy in favor of a republic. A republic has the feature of the public hiring people who will become (in theory at least) highly familiar with the issue and will vote on the proposal in a position of an informed decision. The public on the other hand will largely give it little meaningful thought and mostly just vote the way their gut tells them at the ballot box. Not exactly how we want a government to run if we intend to have long-lasting positive public policy that works for everyone. Additionally, when people can tax “others” to pay for the government services THEY want, it becomes a situation where two wolves and a sheep are voting on what’s for lunch. Nothing good can happen out of it, and our founding fathers knew this, and warned greatly against it.
Legal and administrative challenges are likely
Even supporters acknowledge the measure would be complex to administer; opponents argue it’s unworkable and unconstitutional. Either way, if enacted, you should expect litigation, regulations, audit programs, and valuation disputes to follow quickly. All sorts of legal issue will arise, including Constitutional challenges due to the “Takings Clause” as well as other legal theories that may likely stop the tax in its tracks.
More harm than good will certainly happen, albeit you don’t have to take my word for it
Regardless, when business leaders and wealthy individuals look upon the tea leaves and see the environment is shifting poorly against them, while at the same time other states are rolling out the red carpet, it doesn’t take an economics degree to understand how the tax base could erode to the point that it will take decades of pain for the state to recover and become attractive as a place to do business. Unless California can attract business from other states, and it continues to lose wealth from those same other states, the outcome is as easy to see as watching the same movie for the third time.
California Legislative Analyst’s Office (LAO): warns of tradeoffs and potential longer-term revenue effects (ie tax revenue will decrease, not increase) ; it also describes key mechanics like who pays, how the tax is calculated, and the option (as described in the analysis) to spread payments over time with added cost.
Big-firm / accounting-firm analysis (PwC, EY, Baker Botts): focus heavily on valuation mechanics, trust inclusion, and “how would you even compute this” compliance questions.
California’s budget has faced repeated multibillion-dollar deficits, and projections differ by forecaster, but the direction (ongoing shortfalls) is a real, sourced concern.
California revenue is unusually sensitive to high earners and capital-gains cycles; a tax that triggers taxpayer mobility could increase volatility (this is a common thread in mainstream reporting about the measure)
Who doesn’t see this high tax proposal as a problem? Academic analysis (UC Berkeley economists’ report): argues the tax could raise very large sums over several years and frames it as a targeted way to fund programs, however, even those that suggest it will raise money (instead of the actual obvious long-term impact) acknowledge design choices (like how real estate and business-owned real estate are treated). Yes, I guess it could raise very large sums of tax revenue quickly (ie several years), albeit unreasonably discounts the total impact of migration of wealth to other states that will result in lower tax revenue on a longer time scale. This should be a show stopper and a warning, without addressing even the possibility of an tax revenue.
Selling out tomorrow for a quick fix today is the thing of addicts, and maybe, just maybe California is exactly that right now. An addict with a tax addiction crippling common sense and fiscal planning.

