Building an ADU in San Francisco You Can Sell Separately (AB 1033)
Most ADUs stay part of the property they are built on, forever. San Francisco has opted in to a state law that lets a qualifying ADU become a condominium — with its own title, sold separately. The door is real, and the test for walking through it is strict.
The short answer
Yes, San Francisco opted in — Ordinance 113-25, adopted July 8, 2025 and effective August 10, 2025. But only an ADU that passes every element of a strict eligibility test can be converted and sold separately.
- Application date: the ADU construction application was submitted on or after May 1, 2025 — a submission-date test, not a permit-issuance test.
- Programme: the ADU was built under the State Mandated ADU Program, Planning Code §207.2 only. ADUs under the local §207.1 programme are generally not eligible.
- Lot size: the lot contains four or fewer dwelling units.
- One only: one ADU per lot may be converted and sold separately.
- No JADUs: junior ADUs are excluded.
Miss any one element and the answer is no — however the project is described elsewhere. The full test, element by element, is below.
Sources, as of November 2026: San Francisco Planning’s official summary of the AB 1033 condominium-conversion provisions, and Ordinance 113-25 (Board File 241069), adopted July 8, 2025, effective August 10, 2025; San Francisco Subdivision Code Article 9. Eligibility wording on this page follows those sources exactly.
The decision box
The eligibility test, element by element
Treat this as a checklist where every box must be ticked. There is no partial credit, no rounding, and no substitute element — and the most common mistake is testing the wrong date.
| Element | The test | Your situation — and the fail cases |
|---|---|---|
| 1. San Francisco opted in | Ordinance 113-25 (Board File 241069), adopted July 8, 2025, effective August 10, 2025. | The opt-in is settled — this element is not the obstacle. Everything below is. |
| 2. Application submission date | The ADU construction application was submitted on or after May 1, 2025. | Submitted before May 1, 2025 → out, even if construction or permitting finished much later. This is a submission-date test; it is not a permit-issuance test, whatever secondary sources say. |
| 3. Programme | The ADU must be built under the State Mandated ADU Program, Planning Code §207.2 only. | Built under the local §207.1 programme → out — §207.1 ADUs are generally not eligible. Programme choice, made at application time, decides this years later. |
| 4. Units on the lot | The lot contains four or fewer dwelling units. | Five units on the lot → out. Count the lot’s dwelling units, not just the building you are adding to. |
| 5. How many ADUs | One ADU per lot may be converted and sold separately. | A second ADU on the same lot → out for separate conversion. One convertible unit per lot is the ceiling, not a starting point for negotiation. |
| 6. Unit type | The unit must be an ADU. JADUs are excluded. | A junior ADU → out, regardless of its date, programme or lot. A JADU stays part of the main property. |
Pause on element 2, because it is the one most often gotten wrong. Eligibility turns on when the ADU construction application was submitted — on or after May 1, 2025. It does not turn on when the permit was issued, when construction started, or when the unit was finished. An application submitted in April 2025 whose permit issued in 2026 does not pass. An application submitted in June 2025 passes this element even if everything else took longer. If you are planning a new ADU with separate sale in mind, the submission date is easy to satisfy — it is the programme element, §207.2 only, that needs deciding before you file, because it cannot be changed afterwards.
And if you are weighing §207.2 against the local §207.1 programme for other reasons, weigh the whole picture: programme choice also carries rent consequences if you keep and rent the unit instead of selling it. That decision is laid out on our San Francisco rent-control guide — read it before the programme is locked in, not after.
The process
How “build it and sell it” actually works
Separate sale is not a checkbox on the ADU permit. It is a second, legal process that runs after — and alongside — the building process. In outline:
Build the ADU under §207.2
One ADU, on a lot of four or fewer dwelling units, under the State Mandated ADU Program (Planning Code §207.2), on an application submitted on or after May 1, 2025. Every eligibility element above is created — or lost — at this step.
Convert through the subdivision and condominium process
The ADU is converted into a condominium through San Francisco’s subdivision process, meeting the requirements of Subdivision Code Article 9 — including its tenant protections — and complying with the Subdivision Map Act for the conversion itself. Tenant protections are part of the requirements, not an afterthought: a conversion that involves existing tenancies has obligations a homeowner must understand before starting, with proper advice.
Hold and sell a separate title
The converted ADU becomes a condominium unit with its own title, which can be sold separately from the main property. The resulting condominium is governed under the Davis-Stirling framework — which is where the homeowners’ association in the next section comes from, even on a two-unit lot.
This is the shape of the process as the ordinance and code summary describe it. It is not legal advice, and the conversion step in particular warrants a San Francisco land-use or real-estate attorney working from your title, your tenancies and your programme paperwork.
Illustration only. One lot and one title, converted into two condominium units with separate titles. A diagram of the legal idea — not a subdivision map, and not a representation of any property’s conversion.
Life after conversion
HOA and tenancy-in-common realities
A converted ADU does not float free of the lot it was built on. It becomes a condominium — and a condominium, even a two-unit one, comes with a homeowners’ association under the Davis-Stirling framework. On a two-unit lot that association is small, but it is real: the two owners share a legal structure covering the common elements — the lot, shared walls and systems, insurance and maintenance responsibilities — with governing documents, dues and decision rules to match. If you sell the ADU, you are not just selling a small home; you are creating a two-owner association you will be the other member of. Price that ongoing relationship, and its paperwork, into the decision.
Condo is not the same as a tenancy in common
San Francisco homeowners often meet separate ownership first through a tenancy in common (TIC), where co-owners each hold an undivided share of the whole property, with exclusive use of a particular unit set out by agreement. A condominium is different in the way that matters here: the unit itself is separately titled, and what is shared is the common area, held through the association. AB 1033 conversion produces the condominium form — a separate title for the ADU — not a TIC share. If your property, your financing conversations or your family’s expectations are built around TIC assumptions, reset them before relying on either structure, and take advice on your specific title.
For Victorian and Edwardian buildings especially — where the ADU may sit within or behind a house that already contains several homes — the “four or fewer dwelling units” element and the shared-structure reality deserve early attention. The eligibility count is about the lot, and the association you create will govern a shared, older building, not two detached boxes on an empty parcel.
The decision framework
Sell vs. rent: the maths, as a framework — not a promise
We will not put San Francisco sale prices or rents on this page, because we do not have verified figures for your property and invented ones would steer a six-figure decision. What we can give you is the complete set of inputs. Price each line honestly — with current, property-specific evidence — and the comparison makes itself.
| If you sell the ADU as a condo | If you keep and rent it |
|---|---|
| Input: the price a separately titled ADU condominium on your lot would actually achieve — from comparable separate-title sales, not from ADU construction cost or from the main house’s value per square foot. | Input: the rent this specific unit, in this neighbourhood and condition, would actually achieve — from comparable current rentals, not from listing optimism. |
| Minus: the full cost of building the ADU under §207.2, plus the subdivision and condominium-conversion costs, professional fees and any Article 9 tenant-protection obligations your situation triggers. | Minus: the same full build cost, plus ongoing landlord costs over your holding period — maintenance, insurance, vacancies and management, whether your own time or paid help. |
| Minus: the effect on the main property’s value of no longer owning the ADU, and of sharing the lot through a small condominium association instead of holding one undivided property. | Factor in: the rent-control position of the unit under the programme you chose — the subject of our rent-control guide — because it shapes what “rent it” means over years, not months. |
| Timing question: a sale returns capital at conversion; is that timing worth more to you than a long income stream? | Timing question: renting keeps the asset and the option to convert later, if the ADU stays eligible — is keeping that option worth more than selling now? |
Two questions do most of the work. First: does the achievable separate-sale price, net of build and conversion costs, beat the value of the rental stream plus the retained asset, on your own numbers? Second: what does selling do to the property you are keeping — its value, its shared-structure obligations, and your relationship with the new co-owner next door? Homeowners who can answer both, with priced inputs, rarely need a guide to tell them which way to go.
A limit on the maths above, stated plainly: the conversion costs beyond construction — subdivision, legal, recording and related costs — are not included in any construction figure shown on this site, and they are not sized here, because no verified figure for them exists in our sources. Do not run the framework as if a construction cost were the whole of the sell-side maths; those costs are a separate line you must have quoted by the professionals who handle the conversion.
Plain limits
What we cannot promise
- No blanket promise of eligibility. Eligibility is element-by-element, on your application’s submission date, your programme, your lot’s unit count and your unit’s type. A page — including this one — can state the test; only a review of your actual records can apply it to you.
- No promise of separate-sale approval. Passing the eligibility test opens the subdivision and condominium-conversion process; it does not guarantee its outcome. Subdivision Code Article 9 requirements, including tenant protections, and Subdivision Map Act and Davis-Stirling compliance all have to be met on your facts.
- No invented prices. Nothing on this page states or implies what your ADU would sell or rent for. Any advisor who quotes you a separate-sale value before pricing the inputs in the framework above is guessing with your property.
- Conversion costs are not in the construction maths. Subdivision, legal, recording and related conversion costs are not included in any construction figure on this site and are not sized here — they are not yet sourced. Construction cost is not the whole maths of a separate sale.
- No legal advice. Conversion, tenancy and association questions on a specific property belong with a San Francisco attorney who has your title and documents in hand.
Homeowner questions
AB 1033 in San Francisco — questions, answered
Has San Francisco actually opted in to AB 1033, and since when?
Yes. San Francisco adopted Ordinance 113-25 (Board File 241069) on July 8, 2025, and it took effect on August 10, 2025. The opt-in is in force; the strict part is whether a given ADU qualifies, not whether the city participates.
My ADU application was submitted before May 1, 2025. Am I out?
On that element, yes. Eligibility turns on the ADU construction application submission date — submitted on or after May 1, 2025. It is not a permit-issuance test: a later permit, later construction or a later finish does not cure an earlier submission date.
Does it matter which ADU programme I built under?
Decisively. The ADU must be built under the State Mandated ADU Program, Planning Code §207.2 only. ADUs built under the local §207.1 programme are generally not eligible for separate conversion and sale.
My lot has five units. Can I convert one ADU?
No. The lot must contain four or fewer dwelling units. Five units on the lot fails the test, regardless of the ADU’s date or programme.
Can I convert two ADUs, or my JADU?
Neither. One ADU per lot may be converted and sold separately, and JADUs are excluded from conversion altogether.
What protections apply to tenants during a conversion?
Conversion runs through the subdivision process, including the tenant protections in Subdivision Code Article 9, alongside Subdivision Map Act compliance and Davis-Stirling compliance for the resulting condominium. The specifics depend on your tenancies — which is why this page promises no approval and points tenanted properties to proper advice early.
Keep reading
Related San Francisco guides
AB 956 · From Jan 1, 2027
Two Detached ADUs on One Lot
What changes in 2027, the JADU trade-off, SB 1117 fee relief — and the honest lot-fit test for 25-foot San Francisco lots.
Programme choice · Rent control
Renting It Instead? Check the Rent Rules First
If you keep the unit rather than sell it, programme choice decides its rent-control position. The decision table, before you commit.
District 4 · Sunset
ADUs in the Sunset District
What fits a 25-foot Sunset lot, and what San Francisco permit data actually shows for District 4 homes and their conversions.
Check your property
Start with the eligibility elements you can check today
The checker below is pre-set to San Francisco. Give it your address and what you are planning — a new §207.2 ADU with separate sale in mind, or an existing unit you hope might qualify — and it returns preliminary, plain-language guidance: how your situation lines up against the submission-date, programme, unit-count and one-ADU elements, and what would need professional or city verification. It applies no Marin fees, rules or costs to a San Francisco property, and it makes no promise of eligibility or of separate-sale approval — that honesty is the point of the test above.
Check my lot
FREE · FAST VERDICTStep 1 of 2 — your address and one tap on what you want to build. That is enough for a first verdict; sharpen it afterwards only if you want to.
Every type, answered — not just the one you picked
True cost — the planning band, the fees on record, and what the band leaves out
Not in the band — budget these separately; no honest source lets us put a number on them for your lot, so none is invented:
How long until someone can move in?
Dates that change this decision
What the permit record shows
What would change this answer
Lay your quotes side by side
Print this sheet and write each contractor's figures in a column. Every row is something a comparable bid has to state; a blank in a quote is a question for that contractor, not a saving. The first column is your brief, filled from your answers.
| Line every quote must state | Your brief | Quote A | Quote B | Quote C |
|---|
Check each contractor's licence number on the Contractors State License Board's public lookup (cslb.ca.gov) before you compare prices. Figures in your brief are the rule caps and planning estimates shown above, not bids.
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