Convert the rates into money and the ranking changes. Each additional million of taxable income is worth $99,000 to Washington under its 9.9% levy [1] and $20,000 to Maine under its 2% surcharge [2], a ratio close to five to one [4]. Those are flow taxes on a year's earnings. California's proposed measure is assessed on stock: a taxpayer sitting at $2 billion would owe $50 million once [3], regardless of whether the year was good, and the measure names trusts alongside individual taxpayers [4].
Minnesota's proposal, 1% on taxable wealth above $10 million [7], is the one that matters for scale. Its threshold is a hundredth of California's [5], which is the difference between a levy that reaches a few hundred balance sheets and one that reaches a professional-services partner with a paid-off house.
The California ballot does not resolve into a single number to plan against. Proposition 42 would bar new taxes on control or ownership of individually owned assets, retirement holdings and other personal savings, as well as retroactive taxes, and it is drafted to void the billionaire tax if it outpolls it, even if the tax also passes [6]. Proposition 41 would require pre-election audits of certain tax-related ballot initiatives and audits of special taxes, and would ban enforcement of certain taxes [5]. So the modelling matrix has at least three outcomes, and none of them can be priced before the votes are counted. EY's Damien Martin makes the narrower version of this point: because the California levy is on the ballot rather than in a statute, the analysis is different from analysing legislation, and it remains one factor among others [13].
The exit is where the arithmetic gets soft. David Heilich of Armanino says breaking domicile is not easy once established, particularly in states that audit the question aggressively [9]. Any modelled saving from a move is therefore a gross figure, before the cost of proving the move happened. Meanwhile the spread between origin and destination is widening from the other end: the Tax Foundation counts eight states that lowered individual income tax rates this year, including Indiana, Ohio, North Carolina and Oklahoma [8].
New York City shows what enforcement ambiguity actually costs a household. Baker Tilly's Andy Whitehair says clients have received notices indicating they may be subject to the city's pied-a-terre tax while a court case over the rollout is unresolved, and are asking whether to bother requesting an exemption for a tax that may or may not be in force [12].
Whitehair also argues that advisors may be better placed than CPAs or lawyers to raise these questions, because an adviser collecting an assets-under-management fee and meeting the client often will hear about next year's liquidity event early enough for the timing to matter [11]. He is a director in the national tax practice of an accounting firm [14], which makes the concession more interesting than the usual version. His practical framing is the empty-nester conversation: clients no longer tied to a location should be asked where it makes the most sense financially to live [10]. Washington's 9.9% does not bite until Jan. 1, 2028 [2], which is the one number on this list with enough runway to plan a realisation around.
