ADU permit cost and fee breakdown in Palo Alto, California
GetYourPermit’s researched permit-fee range for a detached accessory dwelling unit in Palo Alto, with category estimates and direct reference links used in our investigation.
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ADU size
California prohibits development impact fees for ADUs of 750 sq ft or less, so the 749 / 750 / 751 steps are worth comparing.
Estimated total
GetYourPermit researched range at 750 sq ft
$7,800 – $18,200
This estimate combines our fee-schedule research and project-planning experience. Actual charges vary by parcel, plans, valuation, utilities, and outside agencies.
Typical planning amount
$12,600
Modeled at the 600 sq ft reference.
Where the money goes
These are fee components within the permit process, not separate approvals.
- Separate planning / zoning fee$400 – $950
Shown only where the City bills Planning or zoning review as a separate fee.
- Building plan check$2,500 – $6,500
The Building Division’s review of the drawings; part of the Building Permit process.
- Building permit issuance$3,929 – $7,346
The permit issuance charge; where plan check is bundled, the combined amount is carried here.
- Separate trade permits$0 – $650
Shown separately only where electrical, plumbing, or mechanical permits are billed outside a combination permit.
- School district fees$450 – $950
Possible school-district developer fees based on current thresholds and scope.
- Utility fees$0 – $850
Possible water, sewer, electrical, meter, or capacity-related charges.
- Processing, inspection & records$350 – $604
Fixed processing, inspection, records, and administrative charges.
- Surcharges, taxes & state fees$171 – $350
Percentage surcharges, construction taxes, and State-mandated charges.
The darker segment is the low end of the range; the full bar is the high end.
Published fee references
Building permit issuance
The permit issuance charge; where plan check is bundled, the combined amount is carried here.
| Fee | Amount | Basis | Source |
|---|---|---|---|
| ADU — stand-alone detached, excluding master permits | $7,346 | Flat fee | Fiscal Year 2027 Adopted Municipal Fee ScheduleLocation: FY 2027 Adopted Municipal Fee Schedule, PDF page 67, General & Miscellaneous Fees — ADU; live Building Permit page, Detached ADU checklistConfirms: The current City schedule lists $7,346 per permit for a stand-alone detached ADU excluding master permits, and the live permit page confirms that detached ADUs require a building permit. |
| ADU — stand-alone detached, master permit | $2,653 | Flat fee | Fiscal Year 2027 Adopted Municipal Fee ScheduleLocation: FY 2027 Adopted Municipal Fee Schedule, PDF page 67, General & Miscellaneous Fees — ADU; live Building Permit page, Master Permit Checklist for Detached ADUsConfirms: The current City schedule lists $2,653 per permit for a stand-alone detached ADU using a master permit. |
| ADU — stand-alone detached, pre-fabricated site-specific related to master permit | $3,929 | Flat fee | Fiscal Year 2027 Adopted Municipal Fee ScheduleLocation: FY 2027 Adopted Municipal Fee Schedule, PDF page 67, General & Miscellaneous Fees — ADUConfirms: The current City schedule lists $3,929 per permit for the stated pre-fabricated, site-specific, master-related path. |
| ADU — stand-alone detached, site construction site-specific related to master permit | $5,481 | Flat fee | Fiscal Year 2027 Adopted Municipal Fee ScheduleLocation: FY 2027 Adopted Municipal Fee Schedule, PDF page 67, General & Miscellaneous Fees — ADUConfirms: The current City schedule lists $5,481 per permit for the stated site-construction, site-specific, master-related path. |
Plan check
Review of your drawings for code compliance.
| Fee | Amount | Basis | Source |
|---|---|---|---|
| Single-family / duplex building plan check | 125% formula | Formula | Fiscal Year 2027 Adopted Municipal Fee ScheduleLocation: FY 2027 Adopted Municipal Fee Schedule, PDF page 70, Plan Review Fees — Building Plan CheckConfirms: The adopted schedule specifies a 125% plan-check formula for single-family and duplex projects. |
Impact fees
Development impact fees. Prohibited for ADUs of 750 sq ft or less.
| Fee | Amount | Basis | Source |
|---|---|---|---|
| Residential development impact-fee exemption for qualifying ADUs | Set by City formula | Formula | Fiscal Year 2027 Adopted Municipal Fee ScheduleLocation: FY 2027 Adopted Municipal Fee Schedule, PDF page 78, Development Impact Fees — ResidentialConfirms: The current schedule explicitly exempts ADUs under 750 square feet from each listed City residential development-impact-fee row; it does not establish a universal fee for larger ADUs. |
Inspection
Field inspections during construction.
| Fee | Amount | Basis | Source |
|---|---|---|---|
| Single-family / duplex building inspection fee lookup | Verify on the City’s official website | Formula | Fiscal Year 2027 Adopted Municipal Fee ScheduleLocation: FY 2027 Adopted Municipal Fee Schedule, PDF page 66, Building Permit Fees — Single-Family / Duplex Residential (Sq. Ft.)Confirms: The current adopted schedule supplies an official area lookup rather than a modelled residential building-permit amount. |
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 Palo Alto before you commit money.
City reference pages for verification
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