California hosts most billionaires yet ranks worst for charitable donors, study shows

California is home to 246 billionaires, the most of any U.S. state, according to an April Oxfam analysis that highlights donors such as MacKenzie Scott, Jensen Huang and Mark Zuckerberg. Yet the Philanthropy Roundtable’s donor-freedom index placed California at the bottom, awarding it just 2.73 out of 10 because of costly registration fees, mandatory audits over $2 million in revenue and limited tax exemptions. The report’s donor-confidence metric gave the state a 0.88 score, far below the nation’s best performer, Montana, which scored 8.

Smaller charities feel the strain most, said attorney Brittnie Panetta, noting that compliance demands can divert resources from mission work. Over 30,000 nonprofits were flagged as non-compliant in an August 2025 hearing, prompting a state portal overhaul. Despite these hurdles, major foundations continue to give large sums, while critics like Elon Musk argue that giving well remains difficult.