The California State Board of Equalization (BOE) is a public agency charged with tax administration and fee collection in the state of California in the United States. The authorities of the Board are making sure counties fairly assess property taxes, collecting excises taxes on alcoholic beverages, and administering the insurance tax program.

The BOE is the only publicly elected tax commission in the United States. It is made up of four directly elected members, each representing a district for four-year terms, along with the State Controller, who is elected on a statewide basis, serving as the fifth member. In June 2017, Governor Jerry Brown signed legislation stripping the Board of many of its powers, returning the agency to its original core responsibilities (originating in the State Constitution in 1879).