The billionaire tax looks likely to fail. Here’s how many millions were spent to defeat it
The roughly $389 million spent to fight Proposition 40, including by putting the tax-restraining Props 41 and 42 on the ballot, overwhelmingly outweighed the $33 million spent to support the proposal.

TL;DR
- Opponents of California's billionaire tax (Prop 40) raised nearly $400 million to defeat it.
- The spending to defeat Prop 40, including supporting Prop 42, far exceeded the $33 million spent in favor.
- Prop 40 is likely to fail, while Prop 42, which bans new personal property taxes, is likely to pass.
- The billionaire tax fight is not the most expensive proposition fight in California history, a record held by 2022's gambling measures (Props 26 and 27) which cost over $450 million.
- Other expensive propositions include Prop 33 (rent control) and Prop 22 (rideshare drivers), with varying degrees of success for proponents and opponents.
- Overall spending on California ballot measures this year is roughly $800 million across 14 measures, setting a new record.