ADU permit cost and fee breakdown in Martinez, California
GetYourPermit’s researched permit-fee range for a detached accessory dwelling unit in Martinez, 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
$5,500 – $13,000
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
$8,800
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$500 – $1,050
Shown only where the City bills Planning or zoning review as a separate fee.
- Building plan check$1,650 – $3,950
The Building Division’s review of the drawings; part of the Building Permit process.
- Building permit issuance$2,000 – $4,750
The permit issuance charge; where plan check is bundled, the combined amount is carried here.
- Separate trade permits$550 – $1,250
Shown separately only where electrical, plumbing, or mechanical permits are billed outside a combination permit.
- School district fees$250 – $800
Possible school-district developer fees based on current thresholds and scope.
- Utility fees$350 – $900
Possible water, sewer, electrical, meter, or capacity-related charges.
- Processing, inspection & records$150 – $250
Fixed processing, inspection, records, and administrative charges.
- Surcharges, taxes & state fees$50
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 |
|---|---|---|---|
| Building and plan-check fee lookup | Verify on the City’s official website | Verify on the City’s official website | Permit CenterLocation: Permit Center, Building PermitsConfirms: The current Permit Center identifies the application-time fee determination but does not render a current numerical table. |
Impact fees
Development impact fees. Prohibited for ADUs of 750 sq ft or less.
| Fee | Amount | Basis | Source |
|---|---|---|---|
| ADU under 750 sq ft impact-fee exemption | $0 | Flat fee | Accessory Dwelling Units and Junior Accessory Dwelling UnitsLocation: ADU page, Permitting CostsConfirms: The live City page says ADUs below 750 square feet are not subject to impact fees. |
| Larger-ADU impact-fee rule | Set by City formula | Formula | Accessory Dwelling Units and Junior Accessory Dwelling UnitsLocation: ADU page, Permitting CostsConfirms: The current City page provides the proportional rule but no current numerical rate. |
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 Martinez before you commit money.
City reference pages for verification
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