City · California
ADU rules in San Diego
These are the primary sources for accessory dwelling unit regulations in San Diego: the city's own zoning code, planning department pages, and permit guides. Start here before talking to anyone: the rules below are what your permit reviewer will apply.
Rules at a glance
On a lot with an existing or proposed single dwelling unit: one attached or detached ADU, plus one ADU within the dwelling or an existing accessory structure, plus one JADU. Multi-dwelling lots: ADUs in up to 25 percent of existing non-livable space plus up to 8 detached ADUs (not exceeding the number of existing units); proposed multi-dwelling structures get up to 2 detached ADUs.
SDMC 141.0302(b)(1)-(b)(3)One attached or detached ADU permitted per single-dwelling-unit premises, in addition to a conversion ADU and a JADU.
SDMC 141.0302(b)(1)(B)ADU floor area counts toward the lot's floor area ratio; JADU floor area does not. An 800 sq ft ADU is exempt from lot coverage, FAR, front setback, and open space limits per Gov. Code 66321(b)(3).
SDMC 141.0302(b)(4), (b)(7), (c)(4)The record owner is not required to live on the same premises as an ADU (SDMC 141.0302(b)(11)). JADUs do require the record owner to reside in the primary dwelling or the JADU under a recorded agreement, with exemptions for government agencies, land trusts, and qualified housing organizations.
SDMC 141.0302(b)(11); 141.0302(c)(1)(E)-(G)Replacement parking is not required when a garage, carport, or uncovered space is demolished or converted for an ADU, except garage/covered spaces in the Beach Impact Area outside a transit priority area. Allowed spaces may be tandem, on lifts, or in setbacks.
SDMC 141.0302(b)(10), (c)(7), (d)(6)ADUs and JADUs are a limited use decided in accordance with Process One (ministerial staff-level review with a building permit) in the base zones marked L in the Chapter 13 use tables.
SDMC 141.0302 (introductory paragraph)STRO: one license per host, one STR dwelling per host citywide. ADUs financed by the San Diego Housing Commission or deed-restricted affordable cannot be sold separately during the restriction term; other ADUs may be conveyed as condominiums under SDMC 141.0302(f).
SDMC 141.0302(a)(8); SDMC 510.0102-510.0104The fine print: 6 caveats that can change the picture
- Coastal Overlay Zone lag: the amendments adopted by O-21836 (effective 10-5-2024) and O-21989 (effective 8-22-2025) do not apply in the Coastal Overlay Zone until the California Coastal Commission certifies them as Local Coastal Program amendments; the Commission certified the Housing Action Package 1.0 ADU rules on Sept 12, 2024, so coastal lots follow the older certified text and IB 400 lists O-21618, O-21758, O-21836, and O-21989 as pending there (editors notes in SDMC 141.0302; IB 400, Jan 2026).
- ADU Home Density Bonus (SDMC 141.0302(d)) survived the 2024-2025 amendments but was tightened: it is unavailable in the RS-1-1 through RS-1-4 and RS-1-8 through RS-1-11 base zones unless the lot is in a High or Highest CTCAC Opportunity Area and planned Residential; inside a Sustainable Development Area each deed-restricted affordable ADU (10-15 year terms) earns one bonus ADU, outside it the cap is one bonus plus one affordable ADU; single-dwelling-zone lots are capped at 4, 5, or 6 total ADUs/JADUs by lot area (Table 141-03A); bonus projects owe a Community Enhancement Fee (waived for very low/low income units in High/Highest Resource areas), require sprinklers, trees, and off-street parking outside transit priority areas.
- In High and Very High Fire Hazard Severity Zones: 4-ft interior side and rear setbacks apply (instead of zero), and Home Density Bonus lots must front an improved street with two evacuation routes and may not be on a cul-de-sac.
- Lots that used the SB 9 urban-lot-split/two-unit regulations (SDMC Ch. 14, Art. 3, Div. 13) cannot add an ADU or JADU except as provided in SDMC 143.1305(c)(1).
- In the Coastal Overlay Zone, conversions and new ADUs must also conform to wetland, sensitive-bluff, coastal-beach, and sea-level-rise regulations (SDMC 141.0302(a)(7)); parking exemptions narrow in the Beach Impact Area.
- ADUs may be sold separately as condominiums (AB 1033 style) under SDMC 141.0302(f)-(g), subject to lienholder consent, Subdivision Map Act compliance, and a 30-day owner-occupant listing preference.
Summarized from San Diego's ordinance text, read July 2026; every row links the code section it came from. Rules often vary by zone and lot, so treat this as orientation, not a permit determination, and confirm with the planning department before you commit to a design.
ADU regulations
- sandiego.govOfficial sourceVerified July 2026https://www.sandiego.gov/development-services/forms-publications/information-bulletins/400
- sandiego.govOfficial sourceVerified July 2026https://www.sandiego.gov/development-services/news-programs/programs/companion-junior-units
- docs.sandiego.govOfficial sourceVerified July 2026https://docs.sandiego.gov/municode/MuniCodeChapter14/Ch14Art01Division03.pdf
Short-term rental rules
Planning to rent your ADU on Airbnb or VRBO? San Diego regulates short-term rentals separately; check these before counting on nightly rental income.
California statewide law also applies
California sets baseline ADU rights at the state level. Where local rules are stricter than state law allows, state law usually wins, so both are worth reading.
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