Seattle does not have a wealth tax. The phrase “Seattle wealth tax” is shorthand for a state-level proposal that would apply to wealthy Washington residents, including those living in Seattle. The best-known version would charge 1% a year on an individual’s worldwide financial assets above $250 million. It has not passed, and it faces serious constitutional problems under Washington law.
What’s Actually Being Proposed
In January 2023, Senator Noel Frame and Representative My-Linh Thai introduced companion bills, SB 5486 and HB 1473, that would create a statewide tax on extreme financial wealth.1Washington Senate Democrats. Sen. Frame, Rep. Thai Introduce Washington State Wealth Tax Instead of taxing what someone earns in a year, the proposal taxes what they own. That distinction matters, both for who gets caught by it and for whether it can survive a court challenge.
Seattle’s earlier attempt at progressive taxation was different. In 2017 the city council passed a 2% tax on individual income above $250,000, expecting a legal fight and hoping to overturn old precedent. The measure lost in court. The current wealth tax proposal is a state effort, not a city one, and would be administered by the Washington Department of Revenue.
Who Would Owe It
The tax would apply only to individuals whose worldwide intangible financial assets exceed $250 million. The Department of Revenue estimated the tax would raise roughly $3.25 billion for the 2025–27 biennium, drawn from a small number of the state’s wealthiest residents. Residency for more than half the calendar year would trigger the tax, so a Seattle resident who spends seven months in the city would have their entire global portfolio measured against the $250 million floor.
The threshold is based on wealth, not annual income. Someone drawing a modest salary can still qualify if their accumulated stock, private equity stakes, or other holdings cross the line. That’s the point: the proposal targets founders and long-tenured employees of companies like Amazon, Microsoft, and Boeing whose compensation came largely in equity that appreciated over decades.
What Counts as Taxable Wealth
The Department of Revenue’s study defines “financial intangible assets” broadly. The taxable base includes cash and cash equivalents, stocks, bonds, treasury bills, mutual funds, index funds, publicly traded options, futures contracts, commodities contracts, annuities, pension funds, and ownership interests in pass-through entities like partnerships and LLCs.2Washington Department of Revenue. Wealth Tax Study Final Report
Real estate is excluded. Primary residences, vacation homes, commercial buildings, and raw land stay subject to existing property taxes and fall outside the proposal. The bill also carves out hard-to-value intangibles: trademarks, patents, copyrights, trade secrets, licenses, customer lists, noncompete agreements, and goodwill.2Washington Department of Revenue. Wealth Tax Study Final Report Those exclusions are practical rather than principled; putting an annual dollar figure on a brand name or customer relationship would produce endless disputes. Cryptocurrency is not explicitly addressed in the text, which leaves an open question for digital asset holders.
How the Bill Would Be Calculated
The math is simple. A flat 1% rate applies to the value of taxable financial assets above the $250 million exemption. A resident holding $300 million in qualifying assets would owe 1% on the $50 million above the threshold, or $500,000 for the year. Someone at exactly $250 million would owe nothing.
Valuation would be measured at the end of the tax year, based on fair market value on December 31. For publicly traded securities that’s straightforward, since closing prices are public. For private company interests it gets much harder.
Valuing Private Holdings
Private company stakes have no market price to look up. The IRS framework for valuing closely held businesses, Revenue Ruling 59-60, rejects mechanical formulas and instead weighs factors like earnings history, dividend capacity, book value, industry conditions, and comparable public company data.
Private interests also typically qualify for valuation discounts. A minority stake is worth less than its proportional share because the holder can’t force a sale or control operations, and a lack-of-marketability discount applies because private shares can’t be sold on a public exchange. Together these adjustments can reduce a naive valuation by 20% to 40%, which at these asset levels translates to millions in tax savings. If the tax ever takes effect, expect the valuation of private holdings to be the main battleground between wealthy taxpayers and the state.
The Constitutional Problem
Washington’s constitution has blocked progressive taxation for nearly a century. Article VII, Section 1 states: “All taxes shall be uniform upon the same class of property within the territorial limits of the authority levying the tax.”3FindLaw. Washington Constitution Art. 7 Section 1 – Taxation Washington courts read “property” broadly to include income and accumulated wealth, not just land and tangible goods.
In 1933, the state supreme court held in Culliton v. Chase that a graduated income tax violated the uniformity requirement. Because income was classified as property, applying different rates to different income levels meant taxing the same class of property at non-uniform rates. That precedent has held through repeated challenges and looms over any effort to tax wealth on a graduated or threshold basis.
The Excise Tax Argument
Supporters frame the wealth tax not as a property tax but as an excise tax on the privilege of holding financial assets in Washington. Excise taxes are not subject to the uniformity clause, so if a court accepts the framing, the constitutional barrier drops.
The 2023 Washington Supreme Court decision in Quinn v. State gave that argument some room. The court upheld the state’s capital gains tax as a valid excise, reasoning that taxpayers do not owe the tax “merely by virtue of owning capital assets.” Instead the tax is triggered by selling or transferring those assets, which the court characterized as “the exercise of rights in and to property” rather than ownership itself.4Washington Courts. Quinn v. State of Washington
Why a Wealth Tax Is Harder to Defend
The Quinn court drew a clear line between taxing a transaction and taxing ownership. The capital gains tax survived because it requires a sale. No sale, no tax. A wealth tax works the opposite way. It reaches you for holding assets on December 31 regardless of whether you bought, sold, or did anything at all that year. The court even defined a property tax as one that “falls upon the owner merely because they are an owner, regardless of the use or disposition made of their property.”4Washington Courts. Quinn v. State of Washington That description fits a wealth tax almost exactly.
The Quinn dissent amplifies the risk. Dissenting justices argued that even the capital gains tax was really a tax on income wearing an excise label, and they noted Washington courts have “consistently invalidated” taxes measured by net income or gain.4Washington Courts. Quinn v. State of Washington If the capital gains tax barely survived a 6–3 vote, a wealth tax with no transactional trigger faces a steeper climb. Any enacted version would draw immediate litigation, and the outcome would likely decide whether Washington can tax accumulated wealth at all without amending its constitution.
Tax Flight and Revenue Risk
The revenue projections assume wealthy residents stay put. Some already haven’t. Jeff Bezos announced his move from the Seattle area to Miami in late 2023. He cited family and Blue Origin operations, but the timing lined up with Washington’s new capital gains tax and active wealth tax discussions. Based on his net worth at the time, Bezos alone would have owed roughly $1.44 billion annually under the proposed tax, or about 45% of the projected total revenue.
That concentration is the weak point of any wealth tax at the state level. A handful of departures can gut the base. Research on Sweden and Denmark found that a one-percentage-point increase in the top wealth tax rate reduced the stock of wealthy taxpayers by about 2%, and when Sweden repealed its wealth tax in 2006, the rate at which wealthy individuals left the country fell by roughly 30%.5National Bureau of Economic Research. Migration Responses and Their Aggregate Economic Implications Washington shares borders with states that have no income or wealth tax, making relocation easier than emigrating.
Supporters answer that most ultra-wealthy residents have deep ties to Seattle through companies, foundations, and social networks, and won’t uproot their lives over a 1% tax. But the math doesn’t require many to leave. If revenue depends on a few hundred people and a small share of them relocate, the projections come apart quickly.
Federal Tax Interactions
If Washington ever enacts a wealth tax, affected residents would want to deduct it federally under the state and local tax (SALT) deduction. For the 2026 tax year, the SALT cap is $40,400 for most filers, with a phase-out that begins at $505,000 in modified adjusted gross income. Above that threshold the cap drops by 30 cents per dollar but cannot fall below $10,000. These expanded caps are scheduled to last through 2029 before reverting to $10,000 in 2030 unless Congress acts.
For someone owing millions under a wealth tax, a $40,400 deduction cap is effectively nothing. Almost the entire wealth tax bill would be nondeductible at the federal level, pushing the true cost above the nominal 1% rate. That’s worth considering for anyone weighing whether to stay in Washington if such a tax passes.
Where the Proposal Stands
SB 5486, the primary wealth tax bill, was referred to the Senate Ways and Means Committee in January 2023 and received a public hearing that March. It was reintroduced in January 2024 with no further action.6Washington State Legislature. SB 5486 – 2023-24 As of 2026, the wealth tax has not passed either chamber.
Separately, the legislature did pass SB 6346, a “Millionaires Tax” scheduled to take effect January 1, 2028, expected to affect about 20,000 households statewide.7Washington Senate Democrats. Millionaires Tax FAQ That’s a different measure covering a much broader group at far lower asset levels, and it should not be confused with the $250 million wealth tax proposal. Its passage does suggest Olympia’s appetite for taxing the wealthy is real, even while the specific wealth tax remains stalled.
If the wealth tax is reintroduced and passes, lawsuits would follow immediately. The core question would be whether taxing someone for holding assets, with no sale or transaction involved, can qualify as an excise under Washington law. Quinn‘s own reasoning suggests it probably cannot, but the court’s willingness to uphold the capital gains tax means the outcome isn’t certain. A loss in court would likely require a constitutional amendment, which needs a two-thirds vote in both chambers and majority approval from voters.