California city planning guide
San Jose ADU Guide: Permits, Fees & Planning Steps
Planning an accessory dwelling unit in San José? Start with the City’s own ADU Universal Checklist, confirm the property-specific constraints, and only then move into plans, fees and permit submittal.
Start here
The City’s Universal Checklist should come before your floor plan.
The City of San José directs ADU applicants to its ADU Universal Checklist to determine whether the property and proposal qualify and to identify issues such as property designations, fire access, hazards and other project conditions. After completing it, homeowners can request basic planner feedback before investing further in design.
Local contacts
Who handles ADU questions in San José?
ADU Ally
Email: adu.ally@sanjoseca.gov
Phone: 408-793-5302
Use the ADU Ally for questions about San José’s ADU permitting process, special ADU pathways and submittal guidance.
Development Services Permit Center
Address: 200 E. Santa Clara St., 1st Floor, San José, CA 95113
General line: 408-535-3555
The Permit Center is the City’s central starting point for planning and building questions.
Planning questions
Email: ZoningQuestions@sanjoseca.gov
Phone: 408-535-3555
After completing the Universal Checklist, ask a planner about unresolved zoning or property-specific questions.
Permit sequence
A practical San José ADU planning path
Complete the ADU Universal Checklist
Use the City checklist to evaluate the lot, project type and property designations. Do not assume a statewide rule answers every parcel-specific question.
Check the parcel and special conditions
Use SJPermits and City resources to investigate conditions such as flood, geologic or seismic hazards, fire-related constraints and other designations that can affect review.
Request basic planner feedback
If the checklist leaves questions, contact the Planning Division or ADU Ally before paying for a detailed design based on an unverified assumption.
Prepare the plan package
Follow the City’s current ADU plan requirements and worksheets. San José’s Building Bulletins page lists ADU-specific documents including the Universal Checklist, building plan worksheet, inspection checklist and owner declaration forms.
Start the permit application
The City’s ADU Service directs qualifying projects into the building-permit plan-review process and then to SJPermits for the application workflow.
Resolve corrections, clearances and inspections
Track every correction and outside-agency clearance separately. Permit approval is not the end of the process; construction must still pass the required inspections.
Choose the right pathway
Some San José ADUs have a different process.
| Planning metric | San José city framework | California state baseline |
|---|---|---|
| New detached ADU size | Up to 1,000 sq. ft. on lots up to 9,000 sq. ft.; up to 1,200 sq. ft. on lots larger than 9,000 sq. ft. under the City allowance. | A compliant local ordinance may set maximums, but must allow at least 850 sq. ft., or 1,000 sq. ft. for an ADU with more than one bedroom. Where there is no compliant local ordinance, a new detached ADU may be up to 1,200 sq. ft. |
| Detached height | A detached one-story ADU is limited to 18 ft.; the City code allows up to 25 ft. for a detached two-story ADU. | A local height limit generally cannot be below 16 ft. for a detached ADU, with higher minimum allowances required in specified transit and other situations. |
| Impact fees | San José’s checklist says school and parkland impact fees do not apply to ADUs under 750 sq. ft.; other permit and project charges can still apply. | Gov. Code § 66311.5 exempts an ADU with 750 sq. ft. or less of interior livable space from impact fees charged by local agencies, special districts and water corporations. |
Important: San José asks applicants to identify whether they are using the City allowance or a State allowance pathway. Do not combine the most favorable number from each column into one project assumption.
Preapproved ADU plans
San José maintains a preapproved ADU program. The City says same-day permit issuance can be available when site-specific documents are accurate and complete, although projects needing certain clearances, variances or deferred structural work can take longer.
The preapproved path has property restrictions, including hazard-related exclusions. Verify eligibility before buying a plan package.
Junior ADUs
San José describes JADUs as units under 500 square feet located within the footprint of a single-family home. They follow a separate set of JADU requirements, so do not apply detached-ADU assumptions automatically.
Unpermitted ADU legalization
San José has a dedicated AB 2533 legalization program for qualifying unpermitted ADUs and JADUs built or converted before January 1, 2020. The City provides a separate checklist, document requirements and submittal process.
Fees
Do not use a generic “San José permit cost.”
San José provides a Building Fee Estimator for a general idea of permitting costs. The City also publishes a current Building and Structure Permits Fee Schedule. Other fees can still depend on the project, reviewing departments and property conditions.
Open San José building permit fees → · Try the City fee estimator →
Before your first call
Collect these property facts first.
- Property address and parcel information
- Whether the lot is in the City of San José jurisdiction
- Existing home type and number of units
- Proposed ADU type: detached, attached, conversion or JADU
- Approximate proposed floor area
- Known setbacks and available yard area
- Garage or structure you may convert
- Known utility locations and service constraints
- Flood, geohazard, seismic or WUI designations found in City tools
- Any unpermitted existing unit or prior work
- Questions you could not resolve from the Universal Checklist
- Current City forms or bulletins you plan to use
Use the rest of the planning system
Connect San José rules to your property and budget.
Testing rental income? Open the ADU ROI Calculator and choose the San Jose source preset →
Official San José sources
Verify the current rule before committing.
- City of San José — Accessory Dwelling Units
- City of San José — ADU Project Process
- City of San José — ADU Service
- City of San José — Building Bulletins & Forms
- City of San José — Building Permit Fees
- City of San José — AB 2533 ADU/JADU Legalization Program
Planning note: ADU Project Planner is an independent educational resource and is not the City of San José, a design professional or a permitting authority. City procedures, forms and fees can change. Re-check the official sources above before paying for design, permits or construction.