Direct answer
The short version
Maybe. In San Jose, the useful first answer is not whether ADUs are allowed in general. It is whether an ADU looks realistic at your specific address after parcel, zoning, setbacks, access, utilities, and source quality are checked.
San Jose scope
Where this applies
ADUOS is San Jose-first. These answers are scoped to San Jose, California and should not be reused as a promise for another city.
ADUOS checks
What we check first
- Address match and parcel identityModeled
- Jurisdiction and San Jose rule fitModeled
- Lot geometry and likely buildable areaModeled
- Detached, attached, conversion, and JADU path signalsModeled
- Visible blockers and Needs review itemsNeeds review
What could change this
The answer can move
- A bad parcel matchNeeds review
- Unresolved frontage or setback interpretationNeeds review
- Utility capacity or service requirementsNeeds review
- Survey, title, or site evidence that changes the lot readNeeds review
Source notes
Why the label matters
The city and state sources say what the framework allows. ADUOS still treats the address-specific answer as Modeled until the parcel evidence is strong enough.
FAQ
Common follow-ups
Is an ADU automatically allowed in San Jose?
No. San Jose has an ADU pathway, but the realistic answer depends on the property and the project shape.
What should I check first?
Start with address and parcel resolution. If the system cannot identify the right parcel, deeper cost or fit answers should stay Needs review.