California Senate Bill 13 (signed 2019, in effect January 1, 2020) — barred impact fees on ADUs under 750 sqft and made them proportional to the main house above that, cut the approval deadline from 120 days to 60, and barred owner-occupancy requirements until January 1, 2025.
Part of the 2019 package with AB-68 and AB-881. It was not the first statewide reform: SB-1069 and AB-2299 took effect in 2017. AB-976 later made the owner-occupancy ban permanent, and the impact-fee line now reads 750 sqft or less of interior livable space.
Part of the BackyardADU California ADU Glossary — plain-English definitions of the regulatory, construction, and financing terms you'll encounter during a California ADU project.