San Francisco allows ADUs on any lot in a zoning district that permits residential use, through two programs: the Local program in Planning Code Section 207.1 and the State program in Section 207.2 (last amended by Ordinance 222-25, effective December 22, 2025). Under the State program a single-family lot can add one converted ADU, one detached ADU of up to 850 sq ft (studio or 1-bedroom) or 1,000 sq ft (2 or more bedrooms) at 18 ft with 4-ft side and rear setbacks, and one 500 sq ft JADU, with no parking, no owner-occupancy and no City impact fees on a lot with 3 units or fewer. Approval is ministerial on a 60-day clock, with all City departments commenting in one virtual Permit Review Roundtable. Budget Planning and DBI fees of roughly 6% of construction cost (about $18,400 on a $300,000 build) and the highest build costs in California, typically $300,000-$550,000 for a detached unit or $120,000-$300,000 for a garage conversion.
San Francisco ADU Overview
San Francisco is one of California's most active ADU markets. The city has issued thousands of ADU permits since streamlining its approval process, with the average San Francisco ADU taking 4-8 months from application to completion. SF's high rents ($2,200-$3,500/month for a 1-bedroom ADU) make the investment math compelling despite higher construction costs. Both attached and detached ADUs are allowed in all residential zones, and the city offers pre-approved ADU plans to speed up permitting. Garage conversions are particularly popular in neighborhoods like the Sunset, Richmond, and Excelsior where two-car garages are common.
New in 2026: Two important state laws took effect January 1, 2026. SB 543 strengthens the deemed-approved provision — if San Francisco fails to act on your ADU application within 60 days, it is automatically approved. If the city fails to bring a non-compliant local ADU ordinance into line after an HCD finding, that ordinance can be rendered null and void so state standards apply. AB 1154 removed JADU owner-occupancy only where the JADU has its own separate bathroom; a JADU that shares sanitation facilities with the main home still requires the owner to live on-site. These changes apply on top of existing protections like AB 976 (no owner-occupancy for detached ADUs) and SB 1211 (up to 8 detached ADUs on multifamily lots).
Zoning & Size Requirements [1][2][3][4][5][6][7]
Yes — San Francisco allows ADUs. A detached ADU can typically be up to 850 sq ft under current California and San Francisco zoning rules.
See what this means for your lot — ask San Francisco ADU builders for a quote →
| Allowed Zones | Any lot in a zoning district that allows residential use, including the RH, RM, RTO and RC districts and the Neighborhood Commercial and mixed-use districts, as long as the lot has an existing or proposed dwelling (Planning Code 207.1(b) for the Local program; 207.2(b) and (d)(2) for the State program). One Local-program limit: an ADU may not eliminate or reduce ground-floor retail space in a Neighborhood Commercial, Chinatown Community Business or Chinatown Visitor Retail district unless it is a Designated Child Care Unit (207.1(c)(12)). Confirm your district on the Property Information Map |
| Max Size (Detached) | State program: 850 sq ft of gross floor area for a studio or 1-bedroom detached ADU and 1,000 sq ft for 2 or more bedrooms on a lot with a single-family home (Planning Code 207.2(c)(1) and (d)(5)(B); Ordinance 222-25 raised the streamlined cap above the 800 sq ft state floor, effective December 22, 2025). A detached ADU on a lot with an existing multifamily building has no maximum size (Planning Director Bulletin No. 3, June 2026). Local program: the same 850 / 1,000 sq ft caps for the one detached rear-yard ADU (207.1(c)(15)(B)). San Francisco measures gross floor area, not interior livable space |
| Max Size (Attached) | State program (the Gov. Code 66314 path): a studio or 1-bedroom attached ADU may be 50% of the existing home's gross floor area or 850 sq ft, whichever is greater; 2 or more bedrooms, 50% or 1,000 sq ft, whichever is greater (Planning Code 207.2(d)(5)(A)). A converted ADU inside existing space has no size cap, and an existing accessory structure may be enlarged up to 150 sq ft for entry and egress only (Bulletin No. 3). Local program: no size limit for attached or converted ADUs (Local ADU Chart, Sept. 2025), but an ADU may take at most 25% of the ground- and basement-floor habitable space of an existing unit unless the Zoning Administrator waives it (207.1(c)(9)) |
| Max Size (JADU) | 500 sq ft of interior livable space, inside the walls of an existing or proposed single-family home including an attached garage (Gov. Code 66313 and 66333(d); Planning Code 207.2(h)). A JADU exists only in the State program on a single-family lot; the Local program has no JADU. It needs at least an efficiency kitchen (cooking appliance, counter and cabinets) and its own entrance, and may be combined with one converted and one detached ADU (Bulletin No. 3) |
| Max Height | State program: 18 ft for a detached ADU on any lot with an existing or proposed dwelling, plus 2 ft for a roof pitch that matches the main house (20 ft total); 25 ft for an attached ADU (Planning Code 207.2(d)(9)). The 18 ft applies citywide with no transit-distance or multistory test. Local program: 16 ft for the detached rear-yard ADU (207.1(c)(15)(A)); a converted ADU has no height limit; other Local ADUs follow the district height limit and may not add a story, except a corner-lot detached garage may add one story within its footprint and a building in a seismic retrofit may be raised up to 3 ft (207.1(c)(5), (c)(7), (f)) |
| Max Units | State program, single-family lot: one converted ADU plus one detached ADU plus one JADU, all on the same lot (Gov. Code 66323; Planning Code 207.2(c)); or instead one attached ADU, which may not be combined with the others (207.2(d)(1)-(3)). State program, multifamily lot: up to 8 detached ADUs, not more than the number of existing units (2 on a proposed building), plus converted ADUs in non-livable space equal to 25% of existing units and at least 1 (Bulletin No. 3). Local program: one ADU inside the building plus one detached rear-yard ADU where the lot has 4 or fewer units or the zoning allows 4 or fewer; unlimited ADUs plus one detached where the lot has more than 4 units, the zoning allows more than 4, or the building is in a mandatory (Building Code Ch. 4D) or voluntary (AB-094) seismic retrofit (207.1(c)(1), (c)(15), (f)). The two programs cannot be combined on one lot |
Setback Requirements [1][2][3][4][5][6][7]
San Francisco requires a rear setback of about 4 ft for a detached ADU, and no additional parking is required. Owner-occupancy is not required — you can rent it out without living on the property.
| Rear Setback | State program: 4 ft from the rear lot line for a new detached or attached ADU; no setback for an ADU within existing living space or an existing accessory structure, or one that replaces an existing structure in the same location and dimensions; for an ADU that is part of new construction the 4 ft applies only to the part outside the buildable area (Planning Code 207.2(d)(7)). Local program: 4 ft for the detached rear-yard ADU (207.1(c)(15)(A)); none for a conversion of existing space; otherwise the district rear yard applies, which is 30% of lot depth in RH, RM-1, RM-2 and RTO districts and 25% in other residential districts (Planning Code 134; ZA Bulletin 5, Sept. 2025), unless the Zoning Administrator waives it for an ADU in an existing building (207.1(g)) |
| Side Setback | State program: 4 ft from each side lot line for a new detached or attached ADU; none for a conversion or a same-footprint replacement; for new construction the 4 ft applies only to portions outside the buildable area (Planning Code 207.2(d)(7)). Local program: 4 ft for the detached rear-yard ADU (207.1(c)(15)(A)); conversions need none; other Local ADUs follow the district, and side yards are required only in RH-1(D) districts (Planning Code 133; ZA Bulletin 5). Building Code fire-separation and opening-protection rules still apply near a lot line |
| Front Setback | The zoning district's front setback applies (Planning Code 132), but the City may not apply front setback, lot coverage, floor area ratio, open space or minimum lot size rules in a way that prevents a State-program ADU of 800 sq ft or less and 16 ft or less with 4-ft side and rear setbacks (207.2(d)). At least half of a required front setback must remain permeable and 20% planted (sf.gov ADU design page). The Local program has no front-setback waiver; its waivers cover density, bicycle parking, rear yard, exposure and open space only (207.1(g)) |
| Parking Required | None. No off-street parking is required for an ADU or JADU under either program, and when a garage, carport or covered parking space is demolished or converted for an ADU the lost spaces need not be replaced; the garage demolition permit is issued together with the ADU permit (Planning Code 207.2(d)(8); sf.gov ADU design page). Under the Local program, removing a tenant's garage, storage or laundry is a severed housing service that needs a just cause or the tenant's written consent (207.1(c)(3)-(4); Rent Ordinance 37.2(r)), and on-site laundry may not be removed unless replaced with equal capacity (207.1(c)(13)) |
| Owner Occupancy | Not required for any ADU under either program (Planning Code 207.1 and 207.2 impose none; Gov. Code 66315). A JADU that shares a bathroom with the main house requires a recorded deed restriction with owner-occupancy in either the JADU or the main home; a JADU with its own bathroom has no owner-occupancy requirement (Gov. Code 66333(b) as amended by AB 1154, effective January 1, 2026; Bulletin No. 3) |
| Min Lot Size | No minimum lot size. Eligibility turns on the district allowing residential use and the lot having an existing or proposed dwelling (Planning Code 207.1(b), 207.2(b)); a minimum-lot-size rule may not be used to block an 800 sq ft, 16 ft ADU with 4-ft setbacks (207.2(d)). DBI's pre-approved plans are drawn for the standard 25-ft-wide lot |
Permit Process & Fees [8][9][10][11][12][13][14][15][16][17][18][19]
An ADU permit in San Francisco goes through a ministerial, by-right review. Typical timeline: 60 days from a complete application under Gov. Code 66317 (SB 543, January 2026: deemed approved if the City does not act). DBI requires every ADU applicant to sign an Application Processing Time Tolling Declaration choosing either to pause the 60-day clock while revising plans or to keep it running, in which case DBI may deny the application if code compliance is not shown within 60 days and revised plans are due at least 10 business days before the deadline. Local-program projects add the 15-day tenant notice, a 30-day Rent Board objection window (up to 90 days more if a tenant objects) and Planning in-house review before the building permit is filed; DBI states that State-program full permits generally have a shorter review and issuance timeline than the Local program. The City publishes no average issuance times. Permit fees: Planning Department building-permit review (Fee Schedule effective August 29, 2025, revised June 15, 2026): new construction $3,502 under $100,000; $3,504 plus 3.855% of cost above $100,000 up to $499,999; $19,226 plus 1.230% above $500,000. Alteration or conversion: $504 under $10,000; $516 plus 5.274% above $10,000; $3,838 plus 3.524% above $50,000; $5,638 plus 3.855% above $100,000; back-check $366. DBI building permit (Building Code Table 1A-A, permits issued on or after July 12, 2026): plan review $1,617 plus $15.60 per $1,000 over $50,000, or $4,011 plus $13.31 per $1,000 over $200,000; permit issuance $677 plus $4.83 per $1,000 over $50,000, or $1,402 plus $4.21 per $1,000 over $200,000; plumbing, electrical, mechanical, Fire, Public Works and Public Health fees are extra (Table 1A-A note 1). SFUSD school facility fee $3.79 per sq ft of added habitable area (2026 Impact Fee Register). Worked example (our calculation, not a published figure): a $300,000 detached ADU pays about $11,214 to Planning plus $5,342 and $1,823 to DBI, roughly $18,400 before trade permits and school fees; DBI says City fees typically run 6-9% of construction cost. Fees are waived for permits that legalize units built without permits before January 1, 2020.
| Approval Process | Both programs need a DBI building permit filed through the PermitSF portal with an ADU Screening Form (elect State/Hybrid or Local and sign the Rent Ordinance affidavit), a Permit Applicant and Authorized Agent form and the 60-day Tolling Declaration. State program (Planning Code 207.2): ministerial review, no CEQA, no Section 311 neighbor notice, no discretionary review, no appeal to the Board of Appeals (Ordinance 222-25), no design review except objective historic standards; a full-permit application is reviewed at a free virtual Permit Review Roundtable where DBI, Planning, Public Works, Fire and SFPUC deliver all comments in one meeting. Local program (207.1): at least 15 calendar days before applying, post a Notice of Addition of ADU and an owner's declaration in the building and mail them to every unit, file the declaration with the Rent Board (tenants have 30 days to object), then file a Project Application (PRJ) with Planning for in-house review and obtain a Planning Approval Letter before DBI will accept the building permit; Zoning Administrator waivers (207.1(g)) and, where the lot has rental units, a recorded Costa-Hawkins regulatory agreement. No Local-program ADU on a lot with an owner move-in eviction in the past 5 years or another no-fault eviction in the past 10 years (207.1(c)(2)) |
| Review Timeline | 60 days from a complete application under Gov. Code 66317 (SB 543, January 2026: deemed approved if the City does not act). DBI requires every ADU applicant to sign an Application Processing Time Tolling Declaration choosing either to pause the 60-day clock while revising plans or to keep it running, in which case DBI may deny the application if code compliance is not shown within 60 days and revised plans are due at least 10 business days before the deadline. Local-program projects add the 15-day tenant notice, a 30-day Rent Board objection window (up to 90 days more if a tenant objects) and Planning in-house review before the building permit is filed; DBI states that State-program full permits generally have a shorter review and issuance timeline than the Local program. The City publishes no average issuance times |
| Permit Fees | Planning Department building-permit review (Fee Schedule effective August 29, 2025, revised June 15, 2026): new construction $3,502 under $100,000; $3,504 plus 3.855% of cost above $100,000 up to $499,999; $19,226 plus 1.230% above $500,000. Alteration or conversion: $504 under $10,000; $516 plus 5.274% above $10,000; $3,838 plus 3.524% above $50,000; $5,638 plus 3.855% above $100,000; back-check $366. DBI building permit (Building Code Table 1A-A, permits issued on or after July 12, 2026): plan review $1,617 plus $15.60 per $1,000 over $50,000, or $4,011 plus $13.31 per $1,000 over $200,000; permit issuance $677 plus $4.83 per $1,000 over $50,000, or $1,402 plus $4.21 per $1,000 over $200,000; plumbing, electrical, mechanical, Fire, Public Works and Public Health fees are extra (Table 1A-A note 1). SFUSD school facility fee $3.79 per sq ft of added habitable area (2026 Impact Fee Register). Worked example (our calculation, not a published figure): a $300,000 detached ADU pays about $11,214 to Planning plus $5,342 and $1,823 to DBI, roughly $18,400 before trade permits and school fees; DBI says City fees typically run 6-9% of construction cost. Fees are waived for permits that legalize units built without permits before January 1, 2020 |
| Impact Fees | None for a State-program ADU or JADU under 750 sq ft of gross floor area, and none of any size on a lot with 3 existing units or fewer (Planning Code 207.2(j)); a larger ADU on a lot with 4 or more units pays impact fees in proportion to the primary unit's gross floor area at the rates in the Impact Fee Register (indexed 2% on January 1, 2026). Section 207.1 contains no parallel exemption for Local-program ADUs; confirm with the Planning Division. SFPUC water and wastewater capacity charges apply only if a new or larger meter is needed (5/8-inch meter: $2,288 water, $6,006 wastewater, FY2025-26 rates); a single-family home adding one ADU usually needs no added water capacity |
| Plan Check | Electronic plan review in Bluebeam Revu with a required Back Check page. Plans must be stamped by a licensed design professional unless the home is wood-frame, under 2 stories plus basement, under 25 ft wide between bearing walls and under 25 ft tall (Information Sheet G-01). An ADU must be at least 220 sq ft with 7.5-ft ceilings in living and sleeping rooms, its own entrance, a rescue window in every bedroom and an exit path of no more than 125 ft to the street. Buildings with 3 or more units and a rear-yard sleeping room may need a fire alarm and ground-floor sprinklers; a fire flow study is required for new floor area, and street tree, Public Works right-of-way, Maher soil and construction-waste requirements can apply |
| Pre-Approved Plans | DBI runs a Pre-approved ADU Plans program in which building designers submit detached-ADU designs for a $2,408 flat review fee; approved designs are meant to be posted on DBI's site for owners to choose and have the designer adapt to their lot. As of September 19, 2026 DBI's page lists no approved designs. Pre-approved plans are drawn for 25-ft lots, are valid only for the current code cycle, cannot be used in slope-protection, landslide, liquefaction, Maher or flood zones, and still need site-specific plan check of Planning Code compliance, soils, fire separation, foundation and SFUSD fees; a separate tolling form applies to permits that use a pre-approved plan |
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Construction Costs [20][21][22][23][24]
Building an ADU in San Francisco typically costs $300,000-$550,000 ($350-$650 per sq ft); a garage conversion runs $120,000-$300,000.
See what this means for your lot — ask San Francisco ADU builders for a quote →
| Average Build Cost | $300,000-$550,000 |
| Cost per Sq Ft | $350-$650 |
| Garage Conversion | $120,000-$300,000 |
| Prefab ADU (Installed) | $180,000-$350,000 |
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Rental Income Potential [25][26][27][28]
A 2-bedroom ADU in San Francisco rents for around $3,700-$5,000/mo, an estimated 6-8% gross rental yield on a $300,000-$550,000 detached build at $3,000-$4,200/mo, before taxes, vacancy and financing; a $120,000-$300,000 conversion yields more.
| Avg Rent (1 Bedroom) | $3,000-$4,200/mo |
| Avg Rent (2 Bedroom) | $3,700-$5,000/mo |
| Short-Term Rental | No. |
| Est. Annual ROI | 6-8% gross rental yield on a $300,000-$550,000 detached build at $3,000-$4,200/mo, before taxes, vacancy and financing; a $120,000-$300,000 conversion yields more. |
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Recent Law Changes
What's Changed Recently
- Ordinance 222-25 (effective December 22, 2025) rewrote Planning Code 207.2: a State-program detached ADU on a single-family lot may now be 850 sq ft (studio or 1-bedroom) or 1,000 sq ft (2 or more bedrooms) of gross floor area instead of the 800 sq ft state floor, 18 ft tall citywide, and State-program ADU permits can no longer be appealed to the Board of Appeals
- Planning Director Bulletin No. 3 (State ADU Program) was reissued June 28, 2026; the Local ADU Program Chart is version September 26, 2025 (posted May 2026); the single-family and multifamily ADU checklists were updated May 8, 2026
- DBI's Building Code fee Tables 1A-A and 1A-B took effect July 12, 2026; Planning's FY2026-27 Fee Schedule (effective August 29, 2025) was revised June 15, 2026; the Development Impact Fee Register was indexed 2% on January 1, 2026
- Ordinance 113-25 (effective August 11, 2025; Planning Code 207.4 and Subdivision Code 1316): one State-program detached ADU (or an attached ADU built with new construction) on a lot with 4 or fewer units, applied for on or after May 1, 2025, may be sold separately as a condominium under Gov. Code 66341; JADUs are excluded
- SB 543 (January 1, 2026): an ADU application is deemed approved if the City does not act within 60 days of a complete application (Gov. Code 66317); AB 1154 (January 1, 2026): JADU owner-occupancy applies only when the JADU shares a bathroom with the main home (Gov. Code 66333(b))
- DBI launched new ADU permitting pages, the Permit Review Roundtable and the Pre-approved ADU Plans program on October 7, 2025; the ADU Design and Permitting Resource Sheet is dated October 6, 2025
- Ordinance 62-24 (effective April 28, 2024) split the ADU rules into Section 207.1 (Local program) and 207.2 (State program); Ordinances 297-24 (January 19, 2025) and 170-25 (October 6, 2025) made conforming edits
Tips for Building an ADU in San Francisco
- Choose the State program unless you need a Planning Code waiver or want unlimited units: it skips the 15-day tenant notice, the Rent Board declaration, Planning in-house review, Section 311 notice and appeals, and gets a single Permit Review Roundtable at no extra charge
- Stack units on a single-family lot under the State program: one converted ADU, one detached ADU (up to 850-1,000 sq ft, 18 ft) and one 500 sq ft JADU can all go on the same lot; an attached ADU cannot be combined with the others
- Keep a State-program ADU under 750 sq ft of gross floor area, or build on a lot with 3 or fewer units, and no City impact fees apply (Planning Code 207.2(j)); only a lot with 4 or more units and a bigger ADU pays proportional fees
- Sign the tolling declaration with care: agreeing to toll pauses the 60-day clock while you revise; refusing keeps the deadline but lets DBI deny a non-compliant application, and revised plans are due 10 business days before day 60
- Converting a garage or ground floor needs no setbacks and no replacement parking, and size is measured as gross floor area, so the existing footprint sets the unit size; under the State program an accessory structure may grow only 150 sq ft, for entry and egress
- If tenants use the garage, storage or laundry you plan to convert, the Local program treats that as a housing service that needs just cause or written consent, and a Local ADU built with waivers on a rental lot goes under rent control by recorded agreement
- The CalHFA ADU grant was closed when last checked and could not be re-verified on September 19, 2026; confirm at calhfa.ca.gov/adu before counting on it
- Cost basis (2026-09-19 re-verification): avg build cost $300,000-$550,000 for a 500-1,000 sq ft detached build per 2026 industry guides ($280,000-$450,000+ CaliFirst Remodel, May 2026; $340,000-$700,000+ ADUWizard 2026; $300,000-$400,000 typical, Custom Home, April 2026); DBI's own floor is at least $125,000 in material and labor plus about 10% for design and 6-9% for City fees | cost per sq ft $350-$650 (conversions $320-$520, detached $420-$700+ per ADUWizard; $350-$500 Custom Home) | garage conversion $120,000-$300,000 ($110,000-$200,000 CaliFirst; $120,000-$150,000+ Custom Home; $160,000-$300,000 ADUWizard) | prefab $180,000-$350,000 all-in including foundation, utilities, crane and permits (ADUscale, May 2026, $180,000-$320,000 statewide; San Francisco factory-built offers start near $300,000 all-in). Rents: HUD FY2027 Fair Market Rent for the San Francisco HMFA is $3,003 (1BR) and $3,697 (2BR); RentCafe August 31, 2026 averages $3,859 and $4,998; Zumper September 19, 2026 listing medians $4,250 and $6,200
- Cost basis (2026-09-19 re-verification): short term allowed: No. An ADU or JADU may not be used as a short-term rental under Administrative Code Chapter 41A; rentals must be for a term longer than 30 days, and the restriction is recorded on title for Local-program ADUs (Planning Code 207.1(d), 207.2(f); Gov. Code 66323(e)) | roi estimate: 6-8% gross rental yield on a $300,000-$550,000 detached build at $3,000-$4,200/mo, before taxes, vacancy and financing; a $120,000-$300,000 conversion yields more. A Local-program ADU built with Planning Code waivers on a lot with rental units is placed under rent control by recorded agreement (207.1(g)-(h)); a State-program ADU is covered by the Rent Ordinance's eviction rules (207.2(g)) but state law generally exempts a newly built unit from rent caps
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Sources & References
All data on this page is sourced from official government records and verified market data. View our full methodology.
- San Francisco Planning Code Sec. 207.1 Local Accessory Dwelling Unit Program (through Ord. 170-25) | American Legal Publishing Municipal Code — Accessed 2026-09-19
- San Francisco Planning Code Sec. 207.2 State Mandated Accessory Dwelling Unit Program (Ord. 222-25, eff. 12/22/2025) | American Legal Publishing Municipal Code — Accessed 2026-09-19
- Planning Director Bulletin No. 3: State Accessory Dwelling Unit Program (updated June 2026) | SF Planning Planning Department — Accessed 2026-09-19
- Local ADU Options for Single- and Multi-Family Buildings, Planning Code Section 207.1 (chart v. 09/26/2025) | SF Planning Planning Department — Accessed 2026-09-19
- Accessory Dwelling Units program page (programs, unit counts, FAQ, legislative history) | SF Planning Planning Department — Accessed 2026-09-19
- Zoning Administrator Bulletin 5: Buildable Area for Lots in RH, RM, RC and RTO Districts (rev. Sept. 2025) | SF Planning Planning Department — Accessed 2026-09-19
- Design an ADU that meets City codes (parking, setbacks, unit and fire requirements) | SF.gov Planning Department — Accessed 2026-09-19
- Get a building permit for an Accessory Dwelling Unit (ADU), step-by-step | SF.gov (DBI) Planning Department — Accessed 2026-09-19
- SF Building Code Table 1A-A Building Permit Fees, July 2026 (permits issued on/after July 12, 2026) | DBI Government Data — Accessed 2026-09-19
- SF Planning Department Fee Schedule FY2026-27 (effective Aug. 29, 2025, updated June 15, 2026), Section 1 Development Application Fee Government Data — Accessed 2026-09-19
- Development Impact Fee Register, rates effective January 1, 2026 | SF Planning Government Data — Accessed 2026-09-19
- Application Processing Time Tolling Declaration Form for Accessory Dwelling Units | DBI Planning Department — Accessed 2026-09-19
- Get your detached ADU plan pre-approved for future use (Pre-approved ADU Plans program, $2,408 fee) | SF.gov (DBI) Planning Department — Accessed 2026-09-19
- Learn about the Permit Review Roundtable | SF.gov (DBI) Planning Department — Accessed 2026-09-19
- Post a notice for your ADU (Local program 15-day notice) | SF.gov (Rent Board / Planning) Planning Department — Accessed 2026-09-19
- Accessory Dwelling Units (ADUs): housing services, Notice and Declaration, tenant objection | SF Rent Board Planning Department — Accessed 2026-09-19
- Check rules for adding an ADU to a building using the Local Program (waivers, Rent Ordinance) | SF.gov Planning Department — Accessed 2026-09-19
- Ordinance 222-25, File No. 250892: State-Mandated Accessory Dwelling Unit Program (approved 11/21/2025) | SF Board of Supervisors Government Data — Accessed 2026-09-19
- Legalize a unit in your home (Unit Legalization Program, pre-2013 units) | SF.gov (DBI) Planning Department — Accessed 2026-09-19
- How Much Does an ADU Cost in San Francisco in 2026? | ADUWizard industry — Accessed 2026-09-19
- ADU Costs in California (2026): City-by-City Numbers (May 28, 2026) | CaliFirst Remodel industry — Accessed 2026-09-19
- ADU Cost Bay Area 2026 (updated April 21, 2026) | Custom Home Design and Build industry — Accessed 2026-09-19
- Prefab ADU in California 2026: Real Cost and Trade-offs (updated May 2026) | ADUscale industry — Accessed 2026-09-19
- Get a building permit for an ADU: DBI cost guidance (at least $125,000; design 10%; City fees 6-9%) | SF.gov Planning Department — Accessed 2026-09-19
- HUD FY 2027 Schedule of Fair Market Rents, San Francisco, CA HMFA Government Data — Accessed 2026-09-19
- HUD FY 2026 Fair Market Rents (FY26_FMRs.xlsx), San Francisco, CA HUD Metro FMR Area Government Data — Accessed 2026-09-19
- Average Rent in San Francisco, CA (updated September 19, 2026) | Zumper Market Data — Accessed 2026-09-19
- San Francisco, CA Rental Market Trends (updated August 31, 2026) | RentCafe Market Data — Accessed 2026-09-19
- Accessory Dwelling Unit (ADU) topic page | SF.gov Planning Department — Accessed 2026-09-19
- Prepare for an ADU project | SF.gov Planning Department — Accessed 2026-09-19
- San Francisco Planning Code Sec. 207.4 Separate Sale and Conveyance of Certain State Mandated ADUs (Ord. 113-25) | American Legal Publishing Municipal Code — Accessed 2026-09-19
- California Government Code Sec. 66323 (streamlined ADUs, as amended by SB 543) Government Data — Accessed 2026-09-19
- California Government Code Sec. 66333 (JADUs, as amended by AB 1154) Government Data — Accessed 2026-09-19
- California Government Code Sec. 66321 (size and height floors) Government Data — Accessed 2026-09-19
- CA SB 543 (2025-2026) Accessory dwelling units and junior accessory dwelling units (chaptered 10/10/2025) Government Data — Accessed 2026-09-19
- Board of Supervisors Ordinances 2025 list (Ords. 113-25, 170-25, 222-25) | sfbos.org Government Data — Accessed 2026-09-19
Frequently Asked Questions
Can I build an ADU in San Francisco?
Yes. ADUs are allowed in Any lot in a zoning district that allows residential use, including the RH, RM, RTO and RC districts and the Neighborhood Commercial and mixed-use districts, as long as the lot has an existing or proposed dwelling (Planning Code 207.1(b) for the Local program; 207.2(b) and (d)(2) for the State program). One Local-program limit: an ADU may not eliminate or reduce ground-floor retail space in a Neighborhood Commercial, Chinatown Community Business or Chinatown Visitor Retail district unless it is a Designated Child Care Unit (207.1(c)(12)). Confirm your district on the Property Information Map in San Francisco. The maximum size for a detached ADU is State program: 850 sq ft of gross floor area for a studio or 1-bedroom detached ADU and 1,000 sq ft for 2 or more bedrooms on a lot with a single-family home (Planning Code 207.2(c)(1) and (d)(5)(B); Ordinance 222-25 raised the streamlined cap above the 800 sq ft state floor, effective December 22, 2025). A detached ADU on a lot with an existing multifamily building has no maximum size (Planning Director Bulletin No. 3, June 2026). Local program: the same 850 / 1,000 sq ft caps for the one detached rear-yard ADU (207.1(c)(15)(B)). San Francisco measures gross floor area, not interior livable space. Owner-occupancy is not required, so you can rent out the ADU.
How much does an ADU cost in San Francisco?
ADU construction in San Francisco typically costs $300,000-$550,000. Garage conversions run $120,000-$300,000, and prefab ADUs cost $180,000-$350,000.
How much can I rent an ADU for in San Francisco?
Average ADU rents in San Francisco are $3,000-$4,200/mo for a 1-bedroom and $3,700-$5,000/mo for a 2-bedroom unit.
Do I need parking for an ADU in San Francisco?
None. No off-street parking is required for an ADU or JADU under either program, and when a garage, carport or covered parking space is demolished or converted for an ADU the lost spaces need not be replaced; the garage demolition permit is issued together with the ADU permit (Planning Code 207.2(d)(8); sf.gov ADU design page). Under the Local program, removing a tenant's garage, storage or laundry is a severed housing service that needs a just cause or the tenant's written consent (207.1(c)(3)-(4); Rent Ordinance 37.2(r)), and on-site laundry may not be removed unless replaced with equal capacity (207.1(c)(13)). Check with San Francisco planning department for the latest California ADU parking rules, as many states have relaxed requirements in recent years.
How long does it take to get an ADU permit in San Francisco?
The permit review timeline in San Francisco is 60 days from a complete application under Gov. Code 66317 (SB 543, January 2026: deemed approved if the City does not act). DBI requires every ADU applicant to sign an Application Processing Time Tolling Declaration choosing either to pause the 60-day clock while revising plans or to keep it running, in which case DBI may deny the application if code compliance is not shown within 60 days and revised plans are due at least 10 business days before the deadline. Local-program projects add the 15-day tenant notice, a 30-day Rent Board objection window (up to 90 days more if a tenant objects) and Planning in-house review before the building permit is filed; DBI states that State-program full permits generally have a shorter review and issuance timeline than the Local program. The City publishes no average issuance times. Permit fees: Planning Department building-permit review (Fee Schedule effective August 29, 2025, revised June 15, 2026): new construction $3,502 under $100,000; $3,504 plus 3.855% of cost above $100,000 up to $499,999; $19,226 plus 1.230% above $500,000. Alteration or conversion: $504 under $10,000; $516 plus 5.274% above $10,000; $3,838 plus 3.524% above $50,000; $5,638 plus 3.855% above $100,000; back-check $366. DBI building permit (Building Code Table 1A-A, permits issued on or after July 12, 2026): plan review $1,617 plus $15.60 per $1,000 over $50,000, or $4,011 plus $13.31 per $1,000 over $200,000; permit issuance $677 plus $4.83 per $1,000 over $50,000, or $1,402 plus $4.21 per $1,000 over $200,000; plumbing, electrical, mechanical, Fire, Public Works and Public Health fees are extra (Table 1A-A note 1). SFUSD school facility fee $3.79 per sq ft of added habitable area (2026 Impact Fee Register). Worked example (our calculation, not a published figure): a $300,000 detached ADU pays about $11,214 to Planning plus $5,342 and $1,823 to DBI, roughly $18,400 before trade permits and school fees; DBI says City fees typically run 6-9% of construction cost. Fees are waived for permits that legalize units built without permits before January 1, 2020.
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