Cal. Rev. & Tax. Code § 18543

For taxable years beginning on or after January 1, 2023, the Franchise Tax Board shall include a checkbox for a taxpayer to indicate on their individual income tax return that they are interested in no-cost or low-cost health care coverage and authorize the Franchise Tax Board to share information from their tax return with the California Health Benefit Exchange for purposes of providing notification under subdivision (b) of Section 100720 of the Government Code.