ADU Permit Fees & Costs in Modesto, California

Everything you need to apply for a adu permit in Modesto, California — documents, fees, steps, and a downloadable submission packet.

Key Facts

Permit required
Yes
Submission method
Online
Typical fee range
$2,700 – $7,920
Review time
Varies by jurisdiction
Inspections
7 inspections required
VerifiedLast verified: Feb 15, 20262 verified sources

Limited Data Available

Some information on this page has not been fully verified. We're working to improve data quality. Always verify with Modesto directly.

Estimated Total Fees

$2,700$7,920

Range based on typical residential solar PV system. Actual fees depend on project valuation and system size.

Fee ComponentRangeConfidence
ADU Permit Fee[1][2]

Building permit fees calculated per Modesto Master Fee Schedule based on estimated construction valuation and square footage. Includes plan review and standard inspections. No impact fees for ADU utility connections.

$1,800 – $4,800
Plan Review Fee[3][4]

Plan review fee is typically 50-65% of the permit fee.

$900 – $3,120
Estimated Total$2,700$7,920

Fees shown as ranges. Always verify the exact amount with Modesto before submission. Additional fees may apply for expedited review or resubmittals.

Generate your permit packet

Get a personalized ADU permit packet for Modesto, California — tailored to your project details.

  • Required forms: Building Permit Application, and more
  • Pre-filled templates: Permit Cover Sheet
  • Fee breakdown: $900–$4,800 estimated total
  • Step-by-step Modesto Community and Economic Development Department portal submission guide
  • Inspection prep checklist (7 items)
  • Personalized for your specific project details
Build My Permit Packet

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Required Documents

Modesto requires the following documents for this permit application.

R

Building Permit Application

Completed City of Modesto building permit application with project scope, property information, and owner/applicant certification

R

Architectural Drawings

Complete architectural drawings signed and sealed by a licensed California architect or professional engineer with floor plans, elevations, sections, and details

R

Site Plan

Site plan showing property boundaries, lot dimensions, setbacks, existing and proposed structures, parking areas, and utility connections

R

Proof of Ownership

Current deed or title report documenting property ownership, required per California Government Code 65852.2 for ADU eligibility verification

R

Utility and Mechanical Plans

Plans showing water, sewer, electrical, and gas connections with separate metering specifications for independent ADU utility service

Permit Process

Follow these steps to submit your permit application through Modesto Community and Economic Development Department.

  1. 1

    Verify ADU Eligibility

    Confirm property meets ADU eligibility requirements under California Government Code 65852.2 and Modesto Municipal Code Chapter 6. Verify property ownership and zoning.

    You'll need: Proof of Ownership

  2. 2

    Submit Building Permit Application

    Submit complete building permit application with all architectural, site, and utility plans to Modesto Community and Economic Development Department

    You'll need: Building Permit Application, Architectural Drawings, Site Plan, Utility and Mechanical Plans

  3. 3

    Plan Review

    Modesto Community and Economic Development conducts plan review for California Building Code and municipal code compliance

  4. 4

    Address Plan Review Comments

    Revise and resubmit plans if necessary to address any plan review comments or required modifications

  5. 5

    Fee Payment and Permit Issuance

    Pay all required permit and inspection fees and receive authorization to begin construction

  6. 6

    Construction Inspections

    Schedule and pass all required inspections throughout construction and upon final completion

Authority Sources

Data on this page is sourced from official records published by the permitting authority. Always verify requirements directly before submitting.

Modesto Community and Economic Development Department

Last verified: February 15, 2026

2 sources referenced

Portal guide
Official page
Fee schedule
Modesto Master Fee Schedule

Verified February 15, 2026

Frequently Asked Questions

Do I need a adu permit in Modesto?
Yes. Modesto requires a adu permit for this type of project. Submitting without a permit may result in fines, required removal, or complications when selling your property.
How long does adu permit approval take in Modesto?
Processing times in Modesto vary depending on project complexity and current review volume. The process involves 6 steps. Contact Modesto Development Services for current timelines.
What documents are required for a adu permit in Modesto?
Modesto requires 5 documents including Building Permit Application, Architectural Drawings, Site Plan, Proof of Ownership, and others. See the full list above for details.
What happens if I build without a adu permit in Modesto?
Building without a permit in Modesto can result in stop-work orders, fines, required removal of work, difficulty selling your property, and insurance complications. It is strongly recommended to obtain proper permits before starting work.
Can PermitMagic help prepare my adu permit submission in Modesto?
Yes. PermitMagic generates a submission-ready packet tailored to Modesto's requirements, including a document checklist, workflow steps, and authority references. Start a permit plan to get your personalized packet.
How much does a adu permit cost in Modesto?
ADU permit fees in Modesto typically range from $2,700 to $7,920, depending on project scope. Fees may include building permit, plan review, and technology surcharges. Verify current fees with Modesto.

Related Permits

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Answer a few project questions and get a adu permit packet for Modesto, California — with every document, form, and fee organized for submission.

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