The short answer: In California, you can sell an ADU separately from the main house only if your local government has adopted an ordinance allowing it under AB 1033 (Gov. Code section 66342), and only by turning the property into a condominium. It is optional for cities, so many have not adopted it. Even where it is allowed, you need a condominium plan, a safety inspection, your lender’s written consent and compliance with the Subdivision Map Act. JADUs cannot be sold separately.
Last verified: October 2, 2026 ยท Written by the ADU Scope editorial team
Key fact: AB 1033 took effect on January 1, 2024. It does not create a right to sell an ADU. It lets a city or county choose to permit it, and it sets the minimum conditions if they do.
Can You Sell an ADU Separately? What AB 1033 Changed
Before AB 1033, California law generally prohibited selling an ADU separately from the primary home, which kept ADUs as rental or family housing rather than starter homes. AB 1033 lets a local agency adopt an ordinance that allows the primary dwelling and the ADU or ADUs to be conveyed separately as condominiums. The law does not increase the number of units allowed on a lot. It only creates separate ownership interests in units that are already allowed.
HCD’s ADU Handbook summarizes this by saying the statute authorizes a local agency to adopt an ordinance allowing separate conveyance of the primary dwelling and ADUs as condominiums (Gov. Code section 66342). The handbook’s own coverage is short, so the statute and local guidance matter more than the handbook for the details.
What stays the same
- The number of units per lot is unchanged by AB 1033.
- Local zoning, building and fire rules still apply.
- The ADU must be a legal, permitted unit. San Diego County’s guidance, for example, requires final building permits, active permits for units under construction, or streamlining under AB 2533 for certain existing units.
Conditions to Sell an ADU Separately in Government Code 66342
If a city or county adopts a separate-sale ordinance, the statute requires several conditions. The table summarizes the main ones, based on the text of section 66342.
| Requirement | What it means |
|---|---|
| Davis-Stirling Act | The condominiums must be created under the Davis-Stirling Common Interest Development Act, which means a homeowners association structure |
| Subdivision Map Act | Must comply with the Subdivision Map Act and the objective requirements of local subdivision ordinances |
| Safety inspection | Before the condominium plan is recorded, the ADU must pass a safety inspection, shown by a certificate of occupancy or a housing quality standards report from a building inspector certified by the U.S. Department of Housing and Urban Development |
| Lienholder consent | Lienholders may refuse consent or condition it; the consent must be in writing and states it is given in the lienholder’s sole and absolute discretion |
| Consumer notice | The local agency must give notice about lender requirements, possible refinancing effects, and the need for lender consent to later changes |
| Utility notice | The owner must notify utilities of the condominium creation and separate conveyance |
| Existing planned developments | You cannot record a condominium plan in an existing planned development without the association’s express written authorization |
The lienholder item is where many projects stall. If you have a mortgage, your lender can say no, and it does not have to give a reason. Talk to the lender before spending money on surveys.
Attention: Creating a condominium usually means creating an HOA, even a tiny two-unit one. That brings rules, shared maintenance duties, insurance questions and possibly dues.
How to Sell an ADU Separately in Practice
The process varies by jurisdiction. This guide uses one detailed example: San Diego County adopted Ordinance No. 10986 on March 4, 2026 (effective April 4, 2026) to implement AB 1033 in the unincorporated area, and amended it in August 2026. San Josรฉ (Ordinance No. 31095, June 2024) and the City of San Diego (2025) have also adopted ADU condominium rules, so check the current code in your own jurisdiction. Its guidance lists documents and steps that give a realistic picture of what a city might require.
Documents San Diego County asks for
- Property owner authorization.
- Written consent from the lienholder.
- HOA approval, if one already exists.
- Utility provider notifications.
- A condominium plan prepared by a licensed surveyor or engineer.
- CC&Rs and HOA bylaws.
Steps in that process
- Prepare all required documentation.
- File a tentative map or tentative parcel map application.
- Obtain approval and pass final inspection or get a certificate of occupancy.
- Record the final map or parcel map.
- Establish the HOA and record the CC&Rs.
- Obtain a new address for the ADU.
Each step has fees and professional costs, including surveyor, engineer and attorney. Reliable published totals are not available, so do not rely on a single figure; ask local professionals for quotes.
Tip: Before anything else, ask the planning department: “Has this jurisdiction adopted an AB 1033 ordinance?” If the answer is no, a separate sale is not available there under this law.
JADUs, Nonprofits and Other Limits
JADUs. Under San Diego County’s guidance, JADUs cannot be sold separately and must remain part of the primary residence. That reflects the nature of a JADU, which is carved out of the main house.
Nonprofit exception. The handbook refers to a separate set of provisions in Government Code section 66341 involving qualified nonprofit corporations, defined under section 66340(b) by reference to 501(c)(3) status. In short, the unit must be built by a qualified nonprofit, the buyer must live there as a primary residence, affordability restrictions run for 45 years, and ownership is structured as a tenancy in common with unequal shares and a repurchase option for the nonprofit. Consult the statute if a nonprofit is involved.
Other states. Washington is a notable example outside California. The Municipal Research and Services Center reports that local governments in the state may not prohibit condominium conveyance of a unit originally built as an ADU, which is a stronger position than California’s opt-in approach.
The financial case should be tested before you commit. A condominium ADU may sell for more than its rental value suggests, but the costs of subdivision, the HOA and the lender conditions can eat into the gain. Run the numbers with a local agent and attorney.
Frequently Asked Questions
Can I sell my ADU separately in California?
Only if your city or county has adopted an AB 1033 ordinance and you complete the condominium process.
Can a JADU be sold separately?
No, according to San Diego County’s guidance; a JADU remains part of the primary residence.
Do I need my lender’s permission?
Yes, if there is a lien. The lender can refuse in its sole discretion.
Do I need an HOA?
The condominiums must be created under the Davis-Stirling Act, which means a common interest development structure.
Is the ADU subject to the same building rules?
Yes. It must pass a safety inspection before the condominium plan is recorded.
Next Steps
- California ADU Laws 2026
- Can My HOA Block an ADU? Rules by State
- Do ADUs Need Separate Utility Meters?
- ADU Impact Fees: When You Pay Them and How to Avoid Them
- Unpermitted ADU in California: How to Legalize It Under AB 2533
General information, not legal advice. Local rules vary and change; confirm with your planning department and a licensed attorney.
Sources: Gov. Code section 66342 (Justia) ยท HCD ADU Handbook, March 2026 ยท San Diego County: Separate Sale of ADUs under AB 1033 (April 2026) ยท MRSC: Accessory Dwelling Units