California’s proposed billionaire tax officially qualified for the November ballot on June 17 after collecting enough signatures to meet state requirements, setting up a high-stakes showdown over how the state will address massive federal healthcare cuts.
The initiative, backed by the Service Employees International Union-United Healthcare Workers West (SEIU-UHW), would impose a one-time 5% tax on the net worth of California residents worth more than $1 billion. Proponents estimate the measure would generate $100 billion for the state, with 90% directed to healthcare programs and 10% to education and food assistance.
The measure comes as the Trump administration’s “One Big Beautiful Bill Act” has slashed federal Medicaid funding. The state Department of Health Care Services projects federal cuts could cost California $30 billion annually, with close to 3 million Californians potentially losing healthcare coverage over the next two years, according to UC Berkeley Labor Center research.
“We are facing literally a collapse of our healthcare system,” Dave Regan, president of SEIU-UHW, said when the campaign launched. The union has invested more than $31 million into the campaign, arguing that billionaires must help backfill the federal funding gap.
The measure has drawn fierce opposition from Silicon Valley billionaires and California Governor Gavin Newsom. Google co-founder Sergey Brin has spent at least $82 million alone to fight the initiative, reportedly relocating to Nevada over tax concerns. Other tech moguls, including Google CEO Eric Schmidt and venture capitalist John Doerr, have donated millions to opposition campaigns. Collectively, opponents have raised $107.9 million as of June 15, according to state campaign finance data.
Newsom has consistently opposed state-level wealth taxes, arguing they drive wealthy residents and businesses out of California. He is reportedly negotiating a potential deal with the union to reduce the tax rate from 5% to 2% in exchange for withdrawing the measure before the June 25 ballot certification deadline. Late Thursday, the Billionaire Tax Now Coalition sent Newsom a letter proposing the 2% alternative as a compromise.
The measure has won support from Vermont Senator Bernie Sanders and former Secretary of Labor Robert Reich. Early polling shows roughly 50% of voters favor the initiative, though support typically declines as ballot measure campaigns progress. Notably, Nvidia CEO Jensen Huang has stated he supports the tax and chose to remain in California despite the proposal.
Legal experts warn that if the measure passes, it will likely face constitutional challenges that could tie up revenue for years. The seemingly retroactive nature of the tax—it applies to residents as of January 1, 2026, even if they have since left the state—invites legal scrutiny. Some economists also worry that billionaires who have already relocated or hidden assets could reduce the actual revenue collected.
Sources
- CalMatters — core facts about measure qualification, revenue estimates, SEIU-UHW backing, opposition spending, and Newsom negotiations.
- The Guardian — details on measure qualification date, billionaire opposition, Sergey Brin’s spending and relocation, and polling data.
- California Health Care Foundation — federal Medicaid cut projections and impact on Medi-Cal.
- CalMatters (healthcare reporting) — projection that 3 million Californians will lose healthcare due to state and federal changes.
