California ADU law · 2026

What changed on January 1, 2026

State ADU law changes every January. These are the 2026 changes that affect a homeowner planning a unit now, from the HCD handbook and the statute.

Five 2025 bills amended state ADU law: AB 1154 (Ch. 507), SB 9 (Ch. 510), SB 543 (Ch. 520), AB 462 (Ch. 491), and AB 130 (Ch. 22). The changes that matter most to a homeowner:

  • JADU owner occupancy now turns on whether the JADU has shared sanitation facilities with the house. Separate facilities means no owner-occupancy requirement.
  • JADUs cannot be short-term rentals, and if rented must be rented for more than 30 days.
  • A 15-business-day completeness clock, with a written list of deficiencies if the application is incomplete, and an appeal route with a 60-business-day final determination.
  • Impact fees restated around interior livable space: none below 750 square feet for an ADU or 500 for a JADU, proportional above that.
  • Coastal Zone applications must be approved or denied within 60 days of a completed application, and are deemed approved if the Coastal Commission misses that window with an existing primary dwelling on the lot.
  • Ordinances that are not filed with HCD within 60 days, or whose findings are not answered within 30 days, are null and void — and the city must then apply state law alone.
  • Several Government Code sections were renumbered, and 66333.5 was added.

Planning a unit this year? The JADU owner-occupancy rule reversed on January 1 and the completeness clock is now 15 business days. Look up your address to see what your city adds, or read the full guide.

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