San Diego waives Development Impact Fees on the first two ADUs at any size up to its City cap, except for an ADU over 750 sq ft on the code's SB 9 two-home path. School fees still apply, and the City lists base plan-check and inspection charges for a detached ADU over 500 sq ft.
Last verified 2026-10-18. Rules change; the City of San Diego Development Services Department has the final word.
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San Diego Municipal Code 142.0640(b)(1)(A) exempts the first two ADUs on a premises from Development Impact Fees regardless of their area. It makes an exception for an ADU over 750 sq ft built through the SB 9 two-home path cited in section 143.1305(c)(1).
San Diego Municipal Code 142.0640(b)(1)(A) and 143.1305(c)(1)Information Bulletin 400 says ADUs and junior ADUs are subject to school fees. The district and proposed unit determine the actual charge; the San Diego Unified rate shown above is not a confirmed fee for every City address.
City of San Diego Information Bulletin 400, FeesAsk the City of San Diego Development Services Department before you rely on these.
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Generally no. San Diego Municipal Code 142.0640(b)(1)(A) exempts the first two ADUs regardless of floor area, except an ADU over 750 sq ft built under the section 143.1305(c)(1) SB 9 two-home path.
City Information Bulletin 400 says both are subject to school fees. For an initial charge estimate, San Diego Unified publishes a residential developer-fee rate of $5.38 per sq ft from May 10, 2026; the district for the address must confirm its charge.
For an initial fee estimate on a detached ADU over 500 sq ft, City Information Bulletin 501 Table 501A lists a base plan-check charge of $8,085.26 and a base inspection charge of $8,401.90. These are published starting amounts; the City must confirm the full permit total for your plans.
Neither. It is a screening from public records, not professional advice, and not a survey, soils report, appraisal, loan offer or permit; every number is an estimate. A licensed designer confirms the final plan, and your city or county gives final approval.