ADU permit cost and fee breakdown in San Diego, California
An early-budgeting estimate of the permit-related fees an accessory dwelling unit is likely to incur in San Diego. These are not official figures.
Prepared by GetYourPermit editorial teamReport an error
ADU size
California generally exempts ADUs under 750 sq ft from development impact fees, so the 749 / 750 / 751 steps are worth comparing.
Estimated total
Estimated total permit fees at 750 sq ft
$20,300 – $54,950
Assumed construction valuation
$270,000
Used only to compute valuation-based fees. It is not a construction quote.
Where the money goes
- Building permit$2,700 – $7,500
The core permit issued by the city building department.
- Plan check$2,500 – $7,000
Review of your drawings for code compliance.
- Impact fees$2,000 – $15,000
Development impact fees. Often waived for ADUs under 750 sq ft.
- School district fees$7,000 – $8,550
Developer fees charged by the local school district.
- Utility connection$5,500 – $15,000
Water, sewer, and electrical connection or capacity charges.
- Inspection$500 – $1,500
Field inspections during construction.
- Technology & surcharges$100 – $400
Records, technology, and general plan surcharges.
- Other$0
Fees that do not fit the categories above.
The darker segment is the low end of the range; the full bar is the high end.
Read before you budget
- Most fee lines are working estimates rather than verified published city rates. Confirm every line with the city before budgeting.
- Some fee items appear more than once, so category totals may double count.
- Some fees are calculated by a formula we could not reproduce and are excluded from the totals.
Fee items
Building permit
The core permit issued by the city building department.
County ADU Permit Fee
$1,200 – $3,000
Estimated range
City of San Diego ADU Building Permit Fee
$1,500 – $4,500
Estimated range
Plan check
Review of your drawings for code compliance.
County ADU Plan Review Fee
$1,500 – $3,500
Estimated range
City of San Diego ADU Plan Check Fee
$1,000 – $3,500
Estimated range
Impact fees
Development impact fees. Often waived for ADUs under 750 sq ft.
California ADU impact-fee waiver under 750 sq ft
$0
Flat fee
All About ADU Permit Fees & WaiversADU Home Density Bonus Program community enhancement fee
$0 – $5,000
Estimated range
How San Diego is Pricing Developers Out of the ADU ...City of San Diego Development Impact Fee
$2,000 – $10,000
Estimated range
School district fees
Developer fees charged by the local school district.
School fee for ADUs over 500 sq ft
$5.17 per sq ft
Per square foot
ADU Permit Costs, Fees & Laws in San Diego (2025 Guide)
Utility connection
Water, sewer, and electrical connection or capacity charges.
City water capacity/connection fee for ADU
$1,000 – $3,000
Estimated range
ADU Permit Costs, Fees & Laws in San Diego (2025 Guide)City sewer capacity/connection fee for ADU
$1,500 – $4,000
Estimated range
ADU Permit Costs, Fees & Laws in San Diego (2025 Guide)San Diego County Water Authority meter fee
$3,000 – $8,000
Estimated range
ADU Permit Costs, Fees & Laws in San Diego (2025 Guide)
Inspection
Field inspections during construction.
City of San Diego Inspection Fee
$500 – $1,500
Estimated range
Technology & surcharges
Records, technology, and general plan surcharges.
City of San Diego Technology Fee
$100 – $400
Estimated range
Other
Fees that do not fit the categories above.
County ADU fee waiver program ended
Verify directly with the city
Verify with city
ADU Information - County of San Diego
These are estimates, not official fees
Use these figures for early budgeting only. They are not a quote, not a government fee determination, and not legal advice. Actual fees depend on your parcel, your plans, your construction valuation, your utility provider, and the fee schedule in force on the day your permit is issued. Confirm every number with San Diego before you commit money.