San Diego Bonus ADU Program:
What You Need to Know
What Is the Bonus ADU Program?
San Diego’s Bonus Accessory Dwelling Unit (ADU) Program allows property owners to build multiple additional units—beyond what state law permits—on single-family and multifamily lots. It was marketed as a way to increase affordable housing, but has become a tool for unregulated density in quiet, residential neighborhoods.
Instead of backyard cottages or granny flats, developers are building multi-unit rental complexes with no public hearings, no parking requirements, and minimal oversight.
What Passed: The Compromise Package
Unit caps based on lot size:
• 4 ADUs on lots <8,000 sq ft
• 5 ADUs on 8,001–10,000 sq ft
• 6 ADUs on lots >10,000 sq ft
• Infrastructure (Community Enhancement) Fee
• 2-story height limit and 1,200 sq ft maximum
• Fire safety limits for cul-de-sacs in high wildfire zones
• Parking required for ADUs not near transit
• Setback increases and fire code alignment
• Allows sale (not just rental) of ADUs