WAFacts

Washington · Statewide ballot measure · Nov. 3, 2026

What Initiative 645 would do

Initiative 645 would repeal Washington’s new 9.9% tax on income over $1 million before it takes effect, and write a broader ban on income taxes into state law. This report goes through the ballot wording, the initiative’s text, the tax it targets, and what the state’s official forecasts say it means for the budget.

Updated Oct. 31, 2026Election Nov. 3, 2026Tax start date Jan. 1, 2028, unless repealed or struck down

Tax rate on Washington taxable income above $1 million9.9%Applies to income earned starting in 2028
Households the Department of Revenue expects to pay~25,000Up from 21,000 in earlier estimates
State revenue lost if repealed, fiscal years 2027–2031$11.4BOfficial fiscal impact statement, July 2026
Share of the state’s 2029–31 revenue forecast from the tax10%$9.4B of $94.1B, September 2026 forecast

What a yes or no vote means

A yes vote

  • Repeals the 9.9% tax on income over $1 million. It would never be collected.
  • Bans state and local taxes on individual income, or measured by it, in state law.
  • Takes effect Dec. 3, 2026.4

A no vote

  • Keeps the tax in law. It would apply to income earned starting Jan. 1, 2028, with first payments in April 2029.
  • Leaves a separate lawsuit over whether the tax is constitutional to the courts.16,17

A yes vote doesn’t repeal the tax cuts passed with the tax. The same 2026 law expanded the Working Families Tax Credit, exempted diapers, over-the-counter drugs and hygiene products from sales tax, and cut business taxes for small firms. The Attorney General’s explanatory statement says those changes remain in place if I-645 passes.1 The law’s intent section says lawmakers intended repeal of the tax to end them, and the revenue the law directed to pay for them would not exist.7

The ballot, line by line

This is the wording voters see. The Attorney General’s office writes the ballot title. A 2022 state law also requires a “public investment impact disclosure” when a measure would repeal or change a tax in a way that affects public spending.2,3,26

Initiative Measure No. 645

Initiative Measure No. IP26-645 concerns state and local taxes.

This measure would repeal a 9.9% tax on annual individual income over $1,000,000; prohibit taxes measured by individual income and taxes on individual income or the receipt of individual income; and define “income.”

This measure would decrease funding for public K-12 education, higher education (including universities and community colleges), and human services (primarily healthcare).

Should this measure be enacted into law?

Ballot title from the Attorney General’s ballot title and summary (May 4, 2026); disclosure from the public investment impact disclosure (July 23, 2026).2,3 Layout simplified; county ballots differ.

What each part means

“repeal a 9.9% tax on annual individual income over $1,000,000”
This is the tax in the 2026 law, Chapter 238, Laws of 2026 (ESSB 6346). Couples share one $1 million deduction, so it applies to household income above $1 million, not each spouse’s.7,8
“prohibit taxes measured by individual income and taxes on individual income or the receipt of individual income”
This part goes beyond the 2026 tax. It would bar the state and local governments from adopting such taxes in the future. Because it’s a statute, not a constitutional amendment, the Legislature could later change it. For two years after enactment that would take a two-thirds vote of each house; after that, the two-thirds requirement lapses.37
“and define ‘income’”
The initiative defines income as “any gain or benefit measured in money derived from an individual’s capital, labor, property, or other source,” and “individual” as “a natural person.”2,5 How far this definition reaches is disputed. See open legal questions.
“This measure would decrease funding for public K-12 education, higher education … and human services”
The law deposits 95% of the revenue in the general fund “to fund” the package’s tax relief and “to make public investments in K-12 education, health care, human services, and higher education,” and 5% in an account for child care and early learning. It creates no dedicated account for the other programs; spending is set in each budget.1,7 The 2022 law requires the disclosure, when a measure’s revenue goes mainly to the general fund, to list “the top three categories of state services funded by the general fund in the current state budget.”38 Both campaigns challenged the wording. The sponsor argued that repealing a tax that collects nothing until 2029 can’t decrease current funding. Judge Chris Lanese upheld the disclosure on Aug. 7 in a separate case brought by activist Arthur West, and the campaigns then set aside their challenges. On Sept. 3 the state Supreme Court split 4–4 on West’s motion, leaving the wording in place.17,27,28

What the initiative’s text does

Initiative 645’s text was filed April 21, 2026, by Let’s Go Washington, the political committee founded by Redmond hedge fund manager Brian Heywood. Supporters submitted about 509,000 signatures; 308,911 valid signatures were required.17,25 The text does four things:

  1. Repeals the tax. It repeals 66 sections of the 2026 law: the tax itself, how its revenue is distributed, how income is calculated, and how the tax is administered.5,18
  2. Bans income taxes in statute. It prohibits state and local taxes on individual income, on its receipt, or measured by it, regardless of source.5 A 2024 law, Initiative 2111, already banned state and local taxes on “any form of individual income.” The 2026 law amended that ban to exempt the new tax.5
  3. Defines “income” and “individual” for the state’s tax code, as quoted above, and directs that the prohibition be construed liberally.5,18
  4. Takes effect 30 days after the election, on Dec. 3, 2026, and applies going forward.4,5

What it does not do

  • It does not repeal the tax cuts and credit expansions passed in the same 2026 law.1
  • It does not expressly repeal the state’s separate capital gains tax, though whether its broader wording reaches that tax is disputed.18,19
  • It does not change the state constitution. It is a statute.37

The tax it would repeal

The Legislature passed ESSB 6346 in March 2026. The Senate voted 27–22 in February and 27–21 on final passage; the House voted 51–46. Gov. Bob Ferguson signed it March 30, 2026.7,9 Washington has not had an individual income tax since 1933.5

Rate
9.9% of Washington taxable income above a $1 million standard deduction. Spouses and registered domestic partners share one deduction.8
Starting point
Federal adjusted gross income, with state adjustments. Not a tax on wealth or assets.5,35
Deductions and credits
Up to $100,000 in gifts to Washington-based charities. Credits for income tax paid to other states, state business taxes paid on the same income, and the state capital gains tax.5
Inflation
The $1 million deduction is indexed to inflation every two years, beginning in 2029.1,8
Who pays
Residents on all income; nonresidents on Washington-source income. The Department of Revenue estimates about 25,000 households.5,14
Where the money goes
95% to the state general fund; starting July 2029, 5% to the Fair Start for Kids account for child care and early learning.1,7
Timing
Applies to 2028 income. First returns and payments due April 2029. No paycheck withholding.4,36
Referendum
Opponents pursued a referendum and an initiative at the same time. The law declares itself necessary to support state government, and on May 4, 2026, in Heywood v. Hobbs, the state Supreme Court held that it can’t be referred to voters. I-645, filed April 21, became the route to the ballot.16,17

The tax cuts in the same law

The law paired the tax with tax reductions, most starting in 2029. The law’s intent section calls it “an integrated reform of the state tax code.”7

  • Working Families Tax Credit: opens the credit to adults 18 and older without children and raises income limits, starting in 2029.8 Senate Democrats estimate this adds about 460,000 households.36
  • Sales tax exemptions for diapers, over-the-counter drugs, and grooming and hygiene products, starting Jan. 1, 2029.8
  • Repeal of the 2025 sales tax on certain services (such as IT services, custom software, temporary staffing and security services), except advertising, starting Jan. 1, 2029.8,36
  • Small business B&O relief: larger monthly small business credits and a higher annual filing threshold, starting Jan. 1, 2029.8
  • Earlier changes that took effect July 1, 2026, including sales tax exemptions for schools and certain nonprofit performances.8

What it means for the state budget

No money has been collected yet. Every number here is a projection of future revenue, and the projections have risen twice since the law passed. Officials caution that they rest on economic modeling, not collections.14

Official estimates of the tax’s revenue have risen with each update

Estimated revenue by two-year budget period, in billions of dollars

  • 2027–29 budget
  • 2029–31 budget
Sources: Department of Revenue fiscal note for the bill as passed10; OFM fiscal impact statement for I-645, which includes the child care share4; Economic and Revenue Forecast Council, September 2026, as reported by the Washington State Standard and the Washington Research Council.12,13 The 2027–29 figures cover only the first year of payments.
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The official fiscal impact statement

Washington law requires the Office of Financial Management (OFM) to estimate each initiative’s fiscal effect. For I-645, OFM estimates the state would collect $11.4 billion less from July 2026 through June 2031: $11.05 billion for the general fund and $377 million for child care and early learning. Repeal would also save the Department of Revenue about $150 million in administration costs over that period, and OFM found no effect on local government revenue.4

Repeal would reduce state revenue by $3–4.4 billion a year starting in 2029

State revenue loss from I-645 by state fiscal year (July–June), in billions of dollars

  • State general fund
  • Fair Start for Kids (child care and early learning)
Source: OFM, Fiscal Impact Statement for Initiative 645, July 2026, based on the June 2026 revenue forecast.4 Amounts differ by year because of when OFM expects payments to arrive. OFM’s statement won’t be updated for later forecasts.14
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How big that is

The state writes its budgets from the official forecast council’s numbers.14 The September 2026 forecast puts the tax at $3.5 billion of the $82.6 billion expected in the 2027–29 budget period (about 4%), and $9.4 billion of $94.1 billion in 2029–31 (about 10%).11,12

The tax would supply about 10% of state revenue in its first full budget period

Forecast revenue for funds subject to the state’s four-year budget outlook, in billions of dollars

  • Tax on income over $1 million
  • All other forecast revenue
Sources: Economic and Revenue Forecast Council, September 2026, via OFM and the Washington Research Council.11,12
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What repeal leaves in place

Because I-645 repeals only the tax, the package’s revenue reductions would stay. The fiscal note written when the bill passed shows the trade-off for 2029–31, the first full budget period. These figures predate the later, higher estimates of the tax, so the comparison shows the structure rather than current totals.10

Repeal removes the tax but not the tax cuts passed with it

Effect of the 2026 law on state revenue, 2029–31, in billions of dollars (estimate at passage)

  • Repealed if I-645 passes
  • Stays in law if I-645 passes
  • Net effect
Source: Department of Revenue fiscal note for ESSB 6346 as passed by the Legislature.10 Sales tax relief includes the new exemptions and the repeal of the 2025 tax on services. Not shown: the Working Families Tax Credit expansion, which is paid as a refund and doesn’t appear as a tax reduction, and lower local sales tax revenue for cities and counties.
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The 2026 law’s intent section says lawmakers intended that repeal of the tax “would reinstate” sales taxes on the newly exempt items and end the new credits.7 That section states intent and doesn’t make those changes itself. The Attorney General’s explanatory statement says the credits and exemptions stay in place if I-645 passes. Undoing them would take further action by the Legislature.1,35

Cities and counties

The sales tax exemptions also reduce local sales tax revenue, by an estimated $277 million, according to the Association of Washington Cities, which takes no position on the measure. The law states an intent to create a city and county account to offset part of that loss. That account isn’t in statute, and its funding would likely depend on the tax.35

The budget the tax would land in

The state already expects shortfalls. In June, OFM warned agencies of “significant budget shortfalls next biennium” and, the Lynnwood Times reported, cautioned them not to count on the new tax.15 After the September forecast, OFM Director K.D. Chapman-See said “Creating a sustainable budget is the work we have ahead of us.” Senate budget chair June Robinson (D-Everett) said lawmakers need “to reduce current spending so that we can balance in fiscal year 2028.” Sen. Chris Gildon (R-Puyallup), the lead Senate Republican budget writer, said much of the forecast increase “comes with an asterisk” because it depends on a tax not collected until 2029.13

What the estimates don’t include

  • People moving. OFM’s statement doesn’t address migration. It does assume 90–95% compliance and reduces reported income by 4.71% to reflect less federal tax enforcement.4 Sponsor Brian Heywood says the estimates wrongly assume a static population and that high earners will leave.14
  • The court case. If courts strike down the tax, the revenue disappears regardless of the vote.14
  • Later forecasts. The next state forecast is due Nov. 16, 2026.11

The court case running in parallel

In Petter v. State of Washington, filed April 9, 2026, in Klickitat County Superior Court, a group of individuals and business associations argue the tax is unconstitutional. A summary judgment hearing is set for Feb. 5, 2027. No ruling has been issued, and the tax’s Jan. 1, 2028 start date stands.16,17

The case turns on a 1933 state Supreme Court decision, Culliton v. Chase, which treated income as property. The state constitution requires property taxes to be uniform and caps them at 1%. The plaintiffs argue that makes a tax applying only to income above $1 million unconstitutional.16,32 In 2023, in Quinn v. State, the court upheld the state’s capital gains tax 7–2 as an excise tax, without revisiting Culliton.31 Sen. Jamie Pedersen (D-Seattle), a lead sponsor of the 2026 law, said a goal was to put the question before the Supreme Court.16

OutcomeWhat happens to the taxWhat happens to the tax cuts in the same law
I-645 passesRepealed Dec. 3, 2026; never collected.4Stay in law unless the Legislature changes them.1
I-645 fails; courts uphold the taxApplies to 2028 income; first payments April 2029.4Take effect as scheduled, mostly in 2029.8
I-645 fails; courts strike down the taxInvalid; never collected.The law says that if a final court ruling invalidates the tax, the entire act is void, including the tax cuts.8

Open legal questions about the initiative itself

The initiative bans taxes “measured by” individual income and defines income broadly. Whether that reaches other existing taxes hasn’t been decided by any court.19

  • Capital gains tax. A legal memo commissioned by the committee backing the tax says there is “a real question” whether the state’s capital gains tax, which it says raises about $500 million a year, falls within the ban, and “a real concern” for wage-based programs such as unemployment insurance and paid family leave.20 The Seattle Times reported that an earlier version called repeal of the capital gains tax “likely.”19 A campaign spokesperson for the initiative said it “repeals only the unconstitutional income tax,” but Heywood said in a text message to The Seattle Times that it does target the capital gains tax.19
  • How courts might read it. University of Washington emeritus law professor Hugh Spitzer called the concern “legitimate” but wrote that “the odds are the courts would not use this language” that way. In a dispute over a similar earlier initiative, the Attorney General’s office called the effect on other taxes, including Seattle’s JumpStart payroll tax, “uncertain,” but added that courts would try to reconcile it with existing law and “would not necessarily invalidate those taxes.”19
  • What the fiscal estimate counts. OFM’s fiscal impact statement counts only the loss of the new tax.4

Campaign claims and the record

Both campaigns make claims that depend on how you frame a tax that hasn’t been collected yet. This table puts each claim next to what official documents say. It doesn’t rule on who is right.

ClaimWhat the record shows
“$13 billion budget hole”
No on 645, voters’ pamphlet6		 The pamphlet says $13 billion “over four years.” The Seattle Times traced the figure to the fiscal note written when the bill passed, which projects $12.9 billion for fiscal years 2029–2032. OFM’s official statement covers fiscal years 2027–2031, which include only three years of collections, and puts the loss at $11.4 billion. The Times noted that citing the figure without the four-year span could leave a misleading impression.4,6,21
“Voting yes … will not cut K-12 education funding”
Jaime Herrera Beutler, former U.S. representative, speaking for Yes on 64529		 The law says the general fund share is to fund the tax relief and “to make public investments in K-12 education, health care, human services, and higher education,” but it sets up no dedicated account for those programs. The ballot disclosure says repeal would decrease funding for K-12, higher education and human services. Which programs change would be decided in future budgets.3,7
I-645 would “raise taxes on 460,000 families”
No on 645, voters’ pamphlet6		 The Attorney General’s explanatory statement says the credit expansion and exemptions stay in law if I-645 passes. The 2026 law’s intent section says lawmakers intended repeal to end them, which would take new legislation.1,7
Without I-645, Olympia could expand the tax “with the simple stroke of a pen”
Yes on 645, voters’ pamphlet rebuttal24		 Lowering the threshold would require a new law; Gov. Ferguson says he would veto it.24,25 A future law could carry the same clause that kept the 2026 law from a referendum, though voters could still use an initiative, as I-645 does.17 I-645 is also a statute: for two years the Legislature could amend it only by a two-thirds vote, and after that the two-thirds requirement lapses.37
Voters have rejected an income tax 10 times
Yes on 645, voters’ pamphlet6		 The Spokesman-Review counts 10 statewide votes on a new income tax since 1933, all failing; the most recent, in 2010, got 36%. Senate Republican Leader John Braun has used 11.22,34 In 1933, in Culliton v. Chase, the state Supreme Court struck down a graduated income tax that had been enacted by initiative.32
Washington’s tax system falls hardest on lower-income families
No on 645, voters’ pamphlet6		 The Institute on Taxation and Economic Policy, a research group whose work generally supports progressive taxes, estimates the lowest-income 20% pay 13.8% of income in state and local taxes and the top 1% pay 4.1%. It ranks Washington’s system the second most regressive.33
The tax hits small business owners
Yes on 645 and the Tax Foundation29,30		 Owners of pass-through businesses pay individual tax on business income. The law gives them a credit for state B&O tax paid on the same income, and lets businesses elect to pay at the entity level.5 Starting in 2029 it also raises the monthly B&O small business credit from $55 to $125 ($160 to $375 for service businesses) and the annual filing threshold to $250,000.8 The Tax Foundation, a research group whose work generally supports low, broad-based taxes, says some Seattle earners could face a combined top rate of 18.037%, counting Seattle’s employer-paid payroll taxes and the WA Cares premium.30

Who is campaigning

Yes on 645 (repeal the tax)

Main arguments: the tax could expand to more people without a vote; voters have rejected income taxes many times; the state has record revenues and should control spending; repeal keeps the tax cuts.6

Voters’ pamphlet committee: Sen. Chris Gildon (R-Puyallup), entrepreneur Jesse Proudman, retired Seattle firefighter/paramedic Patti Mann, and small business owners Viet Nguyen, Semmelle Abraham and Julie H. Olds.6

Money: Vote Yes Repeal the Income Tax had raised $2.04 million and Let’s Go Washington $3.94 million, which also backs two other measures, according to PDC filings through Oct. 20. Donors include Heywood, Lawrence Hughes, Steve Gordon and Madrona Venture Group.23

No on 645 (keep the tax)

Main arguments: the state tax system is tilted against working families; repeal would cut billions from schools and health care; the tax cuts can’t be kept without the revenue that pays for them; any expansion would go to voters.6

Voters’ pamphlet committee: Washington Education Association President Janie White, brewery owner Matt Hipp, nurse Rosa Potts, Washington State Labor Council President April Sims, retired teacher Thom Garrard, and Lindsay Johnson of Planned Parenthood Advocates of Greater Washington.6

Money: No on 645 had raised $12.5 million, about $11.1 million of it from labor unions, including the Washington Education Association, the Washington Federation of State Employees and SEIU, according to PDC filings through Oct. 20.23

Campaign totals change daily. Current figures are on the Public Disclosure Commission’s website. Gov. Ferguson has campaigned against the initiative.22

Timeline

  1. Mar. 11, 2026Legislature gives final approval to the tax (Senate 27–21).7
  2. Mar. 30Gov. Ferguson signs it.7
  3. Apr. 9Constitutional challenge filed in Klickitat County.16
  4. Apr. 21I-645 text filed.17
  5. May 4Supreme Court rules the law isn’t subject to referendum.17
  6. July 2About 509,000 signatures submitted; the measure qualifies in mid-July.17,25
  7. July 23Ballot disclosure and fiscal impact statement published.17
  8. Aug. 7–Sept. 3Courts leave the ballot disclosure in place.17
  9. Sept. 25State forecast raises the tax’s estimated revenue.11
  10. Oct. 31This report.
  11. Nov. 3Election day.17
  12. Nov. 16Next state revenue forecast.11
  13. Dec. 3I-645 takes effect if approved.4
  14. Feb. 5, 2027Court hearing on the constitutional challenge.17
  15. Jan. 1, 2028Tax applies to income from this date, if still in law.8
  16. Apr. 2029First payments due.4

Official voting information is in the Secretary of State’s 2026 voters’ pamphlet.

About this report

  • Official sources first. Ballot wording, fiscal figures and legal summaries come from the Attorney General, the Office of Financial Management, the Department of Revenue, legislative staff and the state forecast council. News reports are used for court proceedings, campaign finance and quotes.
  • Estimates differ by vintage. Revenue figures come from forecasts made at different times and are labeled with their source. None are actual collections.
  • “Fiscal year” means the state fiscal year, July 1 to June 30, named for the year it ends.
  • Advocacy sources are labeled. Where a figure comes from a campaign, a group that takes positions on tax policy, or a memo commissioned by a campaign, the report says so.
  • WA Facts takes no position on I-645.

Sources

  1. Washington Secretary of State, Ballot Title and Explanatory Statement for Initiative IP26-645.
  2. Office of the Attorney General, Ballot title and ballot measure summary for IP26-645, May 4, 2026.
  3. Office of the Attorney General, Public Investment Impact Disclosure for Initiative IP26-645, July 23, 2026.
  4. Office of Financial Management, Fiscal Impact Statement for Initiative 645, July 2026.
  5. House Office of Program Research, Summary of Initiative 26-645, 2026.
  6. Washington Secretary of State, Voters’ pamphlet: Initiative Measure IP26-645 arguments and rebuttals.
  7. Washington Legislature, ESSB 6346, Chapter 238, Laws of 2026 (session law and certification of enrollment).
  8. Washington House of Representatives, House Bill Report, ESSB 6346 as passed House, March 9, 2026.
  9. Washington Senate, Senate Bill Report, ESSB 6346 as amended by House, 2026.
  10. Office of Financial Management, Multiple agency fiscal note, ESSB 6346 as passed by the Legislature, including the Department of Revenue estimate.
  11. Office of Financial Management, “Overall budget picture unchanged as revenue forecasts … show mixed results”, Sept. 25, 2026.
  12. Washington Research Council, “Revenues for 2025–27 and 2027–29 are still lower than expected … but income tax revenue estimates are increased”, Sept. 25, 2026.
  13. Washington State Standard (via Cascadia Daily News), “State’s budget hurdles remain but ‘millionaire’s tax’ could improve outlook”, Sept. 28, 2026.
  14. Washington State Standard (via KUOW), “WA revenue officials: Income tax will bring in more money than first expected”, Aug. 13, 2026.
  15. Lynnwood Times, “OFM sounds alarm on 2027-29 budget shortfalls”, June 7, 2026.
  16. Washington State Standard, “Court battle ignites over WA’s new income tax”, April 8, 2026.
  17. Joe Wallin, The Startup Law Blog, “Washington Initiative 645 (I-645): Polls, Status & What It Does” (court dockets and status timeline), updated Oct. 28, 2026.
  18. Joe Wallin, The Startup Law Blog, “Does IP26-645 Repeal Washington’s Capital Gains Tax? What the Text Says”, July 17, 2026 (revised Sept. 9).
  19. The Seattle Times (via CPA Practice Advisor), “Could initiative to kill Washington’s ‘millionaires tax’ also kill the state’s capital gains tax?”, June 30, 2026.
  20. Pacifica Law Group, Memorandum to Millionaires Tax for WA on IP26-645 (commissioned by the committee supporting the tax), 2026.
  21. The Seattle Times (via Yakima Herald-Republic), “Is I-645 a ‘$13 billion tax break’ for millionaires and billionaires?”, Oct. 21, 2026.
  22. The Spokesman-Review, “$10 million fight brewing over proposal to stop income tax on millionaires”, Sept. 13, 2026.
  23. KTTH Seattle Red, “Unions supply nearly 90% of No on 645 cash, PDC records show” (figures from PDC filings through Oct. 20), Oct. 21, 2026.
  24. KOMO News, “I-645 Millionaires Tax fight raises millions in donations, questions about claims”, Oct. 30, 2026.
  25. The Seattle Times (via The Spokesman-Review), “Initiative to repeal WA ‘millionaires tax’ qualifies for November ballot”, July 16, 2026.
  26. Washington State Standard (via The Spokesman-Review), “Court rebuffs attempt to ax ballot statement on WA income tax measure’s budget effects”, Aug. 21, 2026.
  27. The Center Square (via Sunnyside Sun), “Challenge lost; Washington Supreme Court fractured over income tax repeal fight”, Sept. 3, 2026.
  28. The Center Square (via Omak Chronicle), “Judge upholds income tax ballot disclosure, sparks sponsor outrage”, August 2026.
  29. KUOW, “The millionaires tax is on the WA ballot this fall. Both sides make their case”, Oct. 8, 2026.
  30. Tax Foundation, “Washington Voters Will Decide Whether to Keep or Reject an Income Tax on High Earners”, Oct. 15, 2026.
  31. Cascade PBS, “WA Supreme Court rules capital gains tax constitutional”, March 24, 2023.
  32. Davis Wright Tremaine, “WA’s Income Tax Creep—Will the Millionaires’ Tax Survive Scrutiny?”, April 16, 2026.
  33. Institute on Taxation and Economic Policy, “Washington: Who Pays? 7th Edition” (2024 law, 2023 incomes).
  34. KIRO 7 / MyNorthwest, “WA Senate gives final approval to millionaire tax, sends it to Ferguson’s desk”, March 12, 2026.
  35. Association of Washington Cities, “2026 Initiative 645: Concerning state and local taxes” fact sheet, Aug. 19, 2026.
  36. Washington Senate Democrats, “Millionaires Tax FAQ” (sponsors’ materials).
  37. Washington State Constitution, Article II, Section 41 (amendment of laws approved by the people).
  38. Washington Legislature, SHB 1876, Chapter 114, Laws of 2022 (public investment impact disclosure).