California’s Working Families Party has endorsed Proposition 40, a November ballot measure that would impose a one-time 5% tax on certain California taxpayers with more than $1 billion in assets, with most of the revenue directed toward healthcare.
The Working Families Party said its coalition of more than 30 grassroots organizations and labor unions, representing nearly 100,000 members across California, is backing the measure as a way to address healthcare funding reductions and help preserve access to medical services.
The endorsement adds to the growing list of labor and progressive organizations supporting Proposition 40, although the measure has also faced opposition from several major unions, healthcare organizations, business groups and Democratic leaders.
Under Proposition 40, the state would collect a one-time tax equal to 5% of the wealth of qualifying billionaires. California’s Legislative Analyst’s Office estimates that the measure could generate tens of billions of dollars in temporary state revenue over several years, although the exact amount is difficult to predict because taxpayers could take steps to reduce their liability.
The official state voter guide says the measure’s revenue would be used primarily for healthcare. The proposition is scheduled to go before California voters in the Nov. 3, 2026, general election. “With our endorsement, the Working Families Party is declaring unequivocally that working Californians need healthcare, not more tax breaks for billionaires,” Christina Livingston, chair of the California Working Families Party, said in the announcement.
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“Our members are proud to join the ranks of labor unions and other organizations from around the state in endorsing Prop 40. It’s time we stop the tax breaks for billionaires and save California’s ERs and hospitals,” Livingston said.
Healthcare funding at center of campaign
Supporters of Proposition 40 have linked the measure to federal healthcare funding reductions enacted under President Donald Trump’s administration.
The campaign supporting the proposition says the federal changes could result in millions of Californians losing health coverage and put additional pressure on hospitals, clinics and healthcare workers.
The official voter guide reflects the supporters’ argument that Proposition 40 would raise about $100 billion for healthcare. That figure is a campaign estimate, while the Legislative Analyst’s Office describes the likely state revenue more generally as tens of billions of dollars spread over several years. The measure would direct 90% of its revenue to healthcare, according to the proposition’s supporters. The remaining funds would be allocated under the measure’s provisions.
The campaign has also cited healthcare worker layoffs and potential hospital and clinic closures as reasons for supporting the tax.
Debru Carthan, executive vice president of SEIU-United Healthcare Workers West, said the Working Families Party’s endorsement would strengthen efforts to address healthcare funding pressures.
“Like all of us who support Prop 40, the California Working Families Party refuses to tolerate a status quo where billionaires get even more tax breaks at the expense of ordinary Californians,” Carthan said.
Measure faces organized opposition
Proposition 40 is not supported unanimously by California’s labor movement or Democratic organizations.
The California Secretary of State’s official voter guide lists the California Primary Care Association, California School Boards Association and California Taxpayers Association among organizations opposing the measure.
The Legislative Analyst’s Office has also identified potential fiscal risks. It says the new wealth tax could reduce state income-tax revenue by less than $1 billion annually if billionaires respond by changing their behavior, including potentially leaving California. The state would also incur costs to administer the tax. The debate has produced divisions within organized labor. The Los Angeles Times reported in July that some unions, including the California State Council of Laborers and United Domestic Workers, had opposed Proposition 40, while SEIU California had taken a neutral position.
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Billionaire-backed groups have also entered the campaign against the measure. The Los Angeles Times reported in August that a group opposing Proposition 40 received a $5 million. California’s Secretary of State reported that, through August 2, the principal committee supporting Proposition 40 had reported about $31.4 million in contributions. Committees opposing the measure had reported a combined $11.27 million.
Polling shows a closely watched contest
Recent polling has shown support for Proposition 40, although the measure does not have universal backing.
A Public Policy Institute of California poll conducted September 4-10 found that 52% of likely voters supported the proposition and 46% opposed it. The survey included 1,745 respondents and had a margin of error of plus or minus 3 percentage points, according to SFGATE’s report on the poll. The polling picture contrasts with a 57%-38% result cited by the Proposition 40 campaign in its endorsement announcement. That campaign-commissioned result should therefore be distinguished from the more recent PPIC survey.
Proposition 40 would apply to qualifying taxpayers based on their wealth, rather than imposing a recurring annual wealth tax. The official ballot summary describes it as a one-time 5% tax on certain taxpayers with assets above $1 billion. With the Working Families Party now joining the campaign, Proposition 40 is emerging as one of California’s closely contested economic and healthcare ballot measures for the November election. Voters will ultimately decide whether the state should impose the one-time wealth tax and use the resulting revenue primarily for healthcare.