Details of Public Law 116-260, section 272 , Additional 2020 Recovery Rebates for Individuals
The federal recovery rebate is treated as an advance refundable credit, so it is not included in income for state or federal purposes. (See FTB Legal Ruling 2001-3.)
California has authorized its own stimulus program called the Golden State Stimulus (GSS).
Senate Bill 88 (Stats. 2021, Ch. 8), as amended by Assembly Bill 88 (Stats. 2021, Ch. 12), authorizes the California State Controller to make a one-time GSS tax refund payment to qualified recipients in the amount of either $600 or $1,200. A qualified recipient shall not receive more than one payment.