Washington Governor Bob Ferguson has declined to support an early income tax proposal introduced by Democratic lawmakers, saying the legislation in its current form does not adequately return revenue to residents or address broader affordability concerns.

The draft bill, unveiled this week behind closed doors among legislators and interest groups, would impose a 9.9 percent tax on individual income above $1 million starting in 2028, marking a significant shift in the state’s tax structure if enacted.

Ferguson, a Democrat, had previously endorsed the idea of a so-called “millionaires’ tax” as part of his broader fiscal agenda to overhaul Washington’s reliance on regressive taxes.

However, in a statement released Tuesday he described the current legislative framework as a “good start” that nonetheless falls short of his criteria for fiscal fairness because it does not return a sufficient share of revenue to Washingtonians to ease cost pressures.

He has called for a larger proportion of the projected revenue to be channelled back into tax relief and direct benefits for families and small businesses.

Supporters of the proposed income tax argue it would help modernise a state tax code that currently exempts wages and personal earnings, leaving Washington as one of nine U.S. states without a personal income tax.

Backers see the tax as a tool to address longstanding inequities in the state’s revenue system, noting that lower-income households pay a relatively higher share of their earnings in sales and excise taxes than wealthy residents.

The measure is also expected to generate around $3 billion annually once fully implemented, providing income for expanded social and economic programmes.

The draft plan includes provisions to expand tax credits for low- and moderate-income households, cut sales tax on essential products like baby and hygiene items, and reduce certain business tax burdens.

Yet Ferguson said it still does not go far enough in directing funds to affordability measures he views as critical to improving economic conditions for Washington residents.

It remains unclear how quickly the Legislature can revise the proposal to secure the governor’s backing, with negotiations expected to continue in the coming weeks.

Republican legislators and conservative groups have vocally opposed the plan, arguing that any form of income tax would be unconstitutional under current state law and likely face immediate legal challenges.

Previous ballot initiatives and court rulings have reflected longstanding resistance to income-based levies in the state, and critics warn that introducing such a tax could have far-reaching economic consequences.

Legal challenges and referendums are widely anticipated should the proposal advance.