Permit Required? Required
Typical Fee Range $1,200–$6,000 Includes school impact fees ($5.38/sq ft) and housing impact fees. California state law mandates 60-day review.
Fee Method Valuation-based
Apply Online Apply at City of San Diego Development Services Department →

What's Required in San Diego

  • Combination building permit required for all new ADU construction and conversions
  • Cities must approve/deny complete applications within 60 days per 2026 state law
  • Housing Impact Fee of $0.80 per square foot applies for units over 750 sq ft
  • Full construction plans including energy (Title 24) and stormwater checks required
  • ADU rent must remain affordable for 7 years if using specific density bonus programs
  • Zoning determines max size and density; some SD areas allow 'Bonus ADUs'

How Much Does an ADU Permit Cost in San Diego?

Budget $1,200–$6,000 for the San Diego permit itself (valuation-based), issued by the City of San Diego Development Services Department — but treat that as the entry fee, not the total. ADUs are full dwelling units, so the permit stack usually includes building, electrical, plumbing, and mechanical trade permits, plus plan review. One local note: includes school impact fees ($5.38/sq ft) and housing impact fees. California state law mandates 60-day review. Get an itemized fee estimate from the department before finalizing your budget; the spread between a simple conversion and a new detached build is wide.

ADU Size Limits and Zoning Rules in San Diego

Before drawing plans, check the two gates that sink most ADU projects: size and zoning. Size ceilings vary by lot and ADU type (attached, detached, or conversion), so confirm your specific configuration. Setbacks, height limits, and utility connections layer on top of those rules. The City of San Diego Development Services Department can confirm what your specific lot allows — worth doing before you pay for architectural drawings rather than after.

How to Get a ADU Permit in San Diego

1

Step 1: Project Design

Draft full architectural and structural plans for the ADU unit.

2

Step 2: Submit to OpenDSD

Upload the 'Combination Building' application and Title 24 documents to the portal.

3

Step 3: Plan Review

Review occurs within 60 days; the city identifies needed corrections within 15 days.

4

Step 4: Fee Payment

Pay invoiced building fees, impact fees, and school fees through OpenDSD.

5

Step 5: Full Inspections

Schedule the complete series: Foundation, Framing, Rough MEP, Insulation, and Final.

Frequently Asked Questions

Yes, California law allows ADUs on most residential lots; San Diego also offers a density bonus program.
Permit and impact fees usually range from $1,200 up to $6,000+ depending on unit size and location.
Typically 1,200 square feet for a detached unit, but check specific zoning bonus limits.