Washington millionaires tax debate: Initiative 645 contrasts $3B in revenue v. fears of broader taxes

Supporters and opponents of Washington’s new income tax on millionaires clashed Thursday night in a televised debate, with one side warning repeal would jeopardize billions of dollars for education and health care and the other arguing the tax could eventually expand to more households.

The Seattle Times-KING 5 debate featured former Republican U.S. Rep. Jaime Herrera Beutler, speaking for the campaign supporting Initiative 645, and April Sims, president of the Washington State Labor Council, AFL-CIO, who opposes the repeal measure.

The initiative will appear on the Nov. 3 ballot. A “yes” vote would repeal the tax, while a “no” vote would keep it in place.

The 9.9% tax applies to household income above $1 million and was approved by state lawmakers earlier this year. It takes effect in 2028 and, according to estimates cited by supporters, is expected to generate roughly $3 billion a year.

Sims argued that repealing the tax would give the state’s wealthiest residents a massive tax break while putting health care and education funding at risk.

“This is an attempt by a handful of the wealthiest people in our state to give themselves a $13 billion tax break, while cutting investments in education and healthcare, Sims said. “This measure would decrease funding for public K through 12 education, higher education, including universities and community colleges, and human services, primarily healthcare. So, vote no on Initiative 645.”

Is a broader income tax coming?

Herrera Beutler argued the tax is the first step toward a broader income tax that could eventually affect more Washingtonians.

“The architect of this income tax bill has stated publicly that he wants to expand it to every working Washingtonian,” she said. “So, income tax supporters will say, ‘We want you to think this is only about millionaires,’ but they put every piece in place to expand it to every working Washingtonian. Olympia lawmakers voted against locking in the $1 million threshold.”

She pointed to lawmakers’ decision, several times, not to pass a proposal that would have locked the $1 million income threshold into law.

“Why would they do that if they don’t intend to lower it?” she asked.

The debate over the threshold has grown more significant as some Democratic lawmakers and candidates have supported lowering it. State Rep. Cindy Ryu, a Democrat running for the state Senate, recently said she would support lowering the threshold to household incomes above $250,000. Democratic state Sen. Jesse Salomon has said he would support a $750,000 threshold.

Those positions are separate from the tax currently on the books, which applies to income above $1 million.

The tax also faces a potential legal battle. Opponents contend it violates a 1933 Washington Supreme Court ruling that struck down an earlier state income tax. If voters reject I-645 and keep the tax in place, the courts could ultimately decide whether it is constitutional.

The tax has become a major issue in the 2026 election cycle, with advertising campaigns underway and the debate influencing legislative races and contests for five open seats on the nine-member state Supreme Court.

Ballots are scheduled to be mailed to voters next week ahead of Election Day on Nov. 3.

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