Washington voters decide on Tuesday whether to repeal a 9.9 per cent tax on personal income above $1 million before anyone has paid it. The state's fiscal impact statement says repeal would cost $11.4 billion over the five fiscal years to mid-2031, from a tax that about 30,000 people would owe.
The measure is Initiative 645. It is one of several income tax questions on state ballots today, alongside measures in Colorado, California and North Carolina. Polls close tonight and no outcome is known. The official estimates for each are, and they share a feature: a small number of taxpayers carries most of the money.
What would Washington's Initiative 645 do?
It would cancel the tax created by Engrossed Substitute Senate Bill 6346, passed in the 2026 legislative session. That law levies 9.9 per cent on Washington taxable income above $1 million per individual from 1 January 2028. If voters approve the initiative, it takes effect on 3 December 2026 and the Department of Revenue stops all work on the tax, the Office of Financial Management says.
The revenue has not arrived yet, so the loss is all in later years. No payments are due until April 2029. The statement puts the state's loss at $3.11 billion in fiscal 2029, $4.43 billion in fiscal 2030 and $3.89 billion in fiscal 2031, including money the law sends to a childcare and early learning account. Against that, the revenue department would save about $150 million in administration costs over five years.
The revenue department's savings estimate assumes about 30,000 taxpayers would owe the tax. By our arithmetic, the lost revenue works out to roughly $148,000 per payer in fiscal 2030 and $130,000 in fiscal 2031. Treat those as orders of magnitude: the 30,000 is an administrative count, and the yearly figures include payment timing effects.
What are Colorado voters choosing between?
Two measures that pull in opposite directions. Colorado has taxed income at a single flat rate since 1987, now 4.4 per cent. Amendment 87 would replace it with six brackets running from 3.7 per cent on the first $25,000 of taxable income to 8.4 per cent above $1 million. Legislative Council Staff estimate it would raise $1.972 billion in the 2027-28 budget year, according to the state's Blue Book. The ballot question itself cites $2.7 billion, the maximum allowing for forecast error.
Proposition 136 would cap the income tax rate at the current 4.4 per cent. If both pass, the Blue Book says the outcome is "unclear," and the Legislature or a court would have to resolve the conflict.
The Blue Book's own table shows how the burden falls, using 2023 tax data. By our arithmetic, 46,328 taxpayers with federal adjusted gross income of $1 million or more, about 1.4 per cent of the roughly 3.4 million counted, would pay $1.21 billion more between them, an average of $26,085 each. About 3.36 million others would pay $573 million less, a cut of no more than $325 each.
How do the four measures compare?
| State and measure | A yes vote would | Official revenue estimate |
|---|---|---|
| Washington, Initiative 645 | Repeal the 9.9 per cent tax on income above $1 million before it starts | $11.4 billion less over fiscal 2027 to 2031 |
| Colorado, Amendment 87 | Replace the 4.4 per cent flat tax with rates from 3.7 to 8.4 per cent | $1.972 billion more in 2027-28 |
| Colorado, Proposition 136 | Cap the income tax rate at 4.4 per cent | None cited here; the cap equals the current rate |
| California, Proposition 3 | Make permanent the higher rates on high earners first passed in 2012 | Keeps $5 billion to $15 billion a year from 2031 |
| North Carolina, income tax amendment | Lower the constitutional ceiling on the income tax rate to 3.5 per cent | None published; the rate is already scheduled to fall below the new ceiling in 2027 |
Sources: state fiscal offices and ballot materials, as linked. Compiled by this publication.
California's Legislative Analyst's Office says the top 2 per cent of taxpayers pay the higher rates and about half of all state income taxes. A no vote lets the rates expire in 2031; a yes vote keeps them. The range is wide because much of the income is tied to the stock market. The same voters are also deciding on a one-time tax on billionaires, Proposition 40, which this publication covered last week.
North Carolina's amendment would write a 3.5 per cent ceiling into the state constitution, WUNC reported. The rate is 3.99 per cent now and is scheduled to fall to 3.49 per cent in 2027 under the budget passed in July. The existing ceiling is 7 per cent, according to the Institute on Taxation and Economic Policy. The scheduled cut already brings the rate under the proposed ceiling. What the amendment changes is how far a future Legislature could raise it.
What should readers watch after tonight?
Different dates matter in each state. Washington's initiative, if approved, takes effect on 3 December, a year before the tax would have started. Colorado's new brackets would apply from the 2027 tax year. California's question is about 2031, not next year.
Property tax is on several ballots too, led by Florida's $11.8 billion measure. The test for the income tax questions comes later: whether the official estimates hold once the few thousand taxpayers who carry them file their returns, or move.
Washington figures, including the $11,432,414,000 five-year estimate, the yearly revenue table, the 1 January 2028 start date, the 3 December 2026 effective date of the initiative and the count of about 30,000 taxpayers, are from the Office of Financial Management's fiscal impact statement for Initiative 645, published by the Secretary of State in July 2026. Colorado figures, rate tables, the taxpayer-by-income table based on 2023 data and the description of Proposition 136 are from the Legislative Council Staff's 2026 Blue Book analysis of Amendment 87. California figures are from the Legislative Analyst's Office analysis of Proposition 3 for the 3 November 2026 ballot. North Carolina's ballot wording and current and scheduled rates are as reported by WUNC on 22 September 2026; the existing 7 per cent constitutional ceiling is from the Institute on Taxation and Economic Policy's summary of 2026 ballot measures. Per-payer estimates, shares of taxpayers and the comparison table are this publication's arithmetic. The analysis is our own.
Topics moneyballot measuresmidterm electionsWashingtonColoradoCaliforniaNorth Carolina
