California ADU Laws & Bills Guide (2020–2026)
California’s ADU laws have changed significantly every year since 2020 – and keeping up with what’s actually allowed on your property isn’t easy.
This guide tracks every major state bill affecting ADU and JADU construction in California, from the foundational 2020 reforms through the latest 2026 legislation.
Use the search bar to look up a specific bill number, or filter by year and status to see what’s currently in effect, what’s upcoming, and what it means for your project. Each entry includes the key provisions, practical implications for homeowners, and links to official bill text where relevant. Note that local rules vary significantly by city — always confirm requirements with your planning department or a licensed ADU professional before moving forward.
California ADU Laws & Bills
A searchable reference guide to California ADU legislation — search by bill number, year, or topic
Year
Status
30 bills shown
Key
Senate Bill (SB)
Assembly Bill (AB)
✓ In Effect
⏳ Upcoming
◈ Pending / Watch
2026+ — Active & Upcoming4 bills
Updated Apr 2026
SB 79
Transit / Density⏳ Jul 1, 2026
Transit-Oriented Development: Mandatory Upzoning Near Major Transit Stops
Effective July 1, 2026, overrides local zoning near major transit stations in 8 California counties — requiring cities to allow significantly denser housing within ½ mile of qualifying stops, regardless of existing local zoning. State standards apply automatically if cities don't comply.
Which Counties Are Affected
SB 79 applies to "urban transit counties" — those with 15 or more passenger rail stations. Currently 8 counties qualify: Los Angeles, Orange, San Diego in Southern California; San Francisco, Alameda, San Mateo, Santa Clara, and Sacramento in Northern California.
What It Requires — Density by Proximity
Projects within ½ mile of a qualifying transit stop ("major transit stop" per Public Resources Code Section 21064.3) must be allowed as a permitted use if they meet these thresholds:
- Minimum 5 dwelling units per project
- Closest to transit (Tier 1): heights of up to 95 feet, density of at least 30 units per acre
- Further out (Tier 2): heights of up to 55 feet, density thresholds still significantly above most single-family zoning
- Residential floor area ratio (FAR) standards are set by proximity tier
- Units over 10 total in a project must meet basic inclusionary housing requirements
- Average unit size cannot exceed 1,750 net habitable sq ft per project
Key Protections Built Into the Law
- Cannot demolish existing rent-controlled housing or deed-restricted affordable housing to qualify
- Sites in high fire hazard zones, flood zones, or certain industrial employment hubs can be exempted
- Cities can develop alternative "TOD Alternative Plans" — but those plans must be approved by HCD
- Cities have until July 1, 2026 to adopt compliant zoning or HCD-approved alternative plans; after that, state standards apply automatically
- Starting Jan 1, 2027: cities that deny a qualifying project in a high-resource area are presumed to be in violation of the Housing Accountability Act and are immediately liable for penalties
Transit Agency Property
SB 79 also allows transit agencies to adopt their own zoning standards for agency-owned property within TOD zones — and those standards override local zoning. This opens up transit agency-owned parcels (bus yards, parking lots near stations) for housing development.
What this means for homeowners: If your property is within ½ mile of a qualifying rail or BRT stop in one of these 8 counties, your development potential may increase substantially after July 2026. This is most relevant for clients with multi-unit investment goals, not typical single-family ADU projects. But it fundamentally changes neighborhood zoning context for properties near the Expo Line, Gold Line, Purple Line, BART, Metrolink, and major bus rapid transit corridors.
📄 Official Bill Text ↗
AB 130
CEQA / Infill✓ In Effect
Powerful New CEQA Infill Exemption for Housing Projects
Created a broad new exemption from California Environmental Quality Act (CEQA) review for qualifying infill housing projects. Many multi-family and mixed-use projects on infill sites no longer require a full environmental review process, dramatically reducing entitlement timelines.
Key Provisions
- Qualifying infill projects on sites up to 4 acres are exempt from CEQA environmental review
- Applies to residential, mixed-use, and affordable housing projects meeting objective standards
- Local governments must take final action on AB 130-exempt projects within 30 days of completing Tribal consultation
- SB 158 (signed same day) clarified the shot-clock timing to avoid conflicts with Housing Accountability Act deadlines
Primarily relevant for clients with larger multi-family or mixed-use infill projects. CEQA exemption dramatically reduces entitlement timelines and costs for qualifying projects. For standard ADU-only projects, CEQA generally doesn't apply anyway — but this is a major development for investors thinking bigger.
New
AB 920
Permitting / Digital⏳ Portals by Jan 2028
All Major Cities Must Create Online ADU & Housing Permit Portals
Requires cities and counties with populations of 150,000 or more to establish centralized online portals for housing development project applications — including ADUs — by January 1, 2028. The portals must allow online submission and real-time status tracking.
Key Provisions
- All cities and counties with 150,000+ residents must have an online housing project application portal by January 1, 2028
- Portals must allow online application submission and display real-time application status
- Jurisdictions can delay implementation to January 1, 2030 if they begin procurement of the required permit system by January 1, 2028
- Covers housing development projects broadly — including ADU applications
This means every major California city — LA, San Diego, San Jose, SF, and hundreds of others — will eventually have end-to-end digital ADU processing with trackable status updates. For homeowners, this eliminates the current frustration of not knowing where your application stands. Won't be fully in place until 2028, but the law is on the books now.
2026 Session
Watch List◈ Monitoring
New Bills Being Introduced — 2025–26 Legislative Session
The 2025–2026 California legislative session is active and new ADU-related bills are introduced regularly. This guide is updated as notable bills advance toward becoming law.
Where to Track New Bills
- California Legislature: leginfo.legislature.ca.gov
- HCD ADU Page: hcd.ca.gov/policy-research/accessory-dwelling-units
- Maxable Blog: maxablespace.com/blog
Trends to Watch
Continued expansion of multi-family ADU rights, coastal permit streamlining as SB 1077 guidance is finalized (July 2026 deadline), new ADU financing programs, post-LA-fires emergency housing reconstruction legislation, and further enforcement teeth around city compliance with ADU processing timelines.
2025 — Enforcement, Streamlining, Coastal & JADU Reforms9 bills
Updated Apr 2026
SB 543
Cleanup / Fees / Units✓ In Effect
Major Cleanup: Faster Processing, Size Definitions, Fee Exemptions + 3 ADUs & a JADU Now Possible on Single-Family Lots
Wide-ranging cleanup bill with several practical improvements — but its most significant breakthrough (confirmed by HCD in January 2026 guidance letters) is that single-family homeowners can now combine Government Code sections 66314 and 66323 to potentially build 3 ADUs plus a JADU on a single property.
Processing Improvements
- 15-day completeness review: Cities must determine if your ADU/JADU application is complete within 15 business days — and provide a written list of anything missing. If they miss this deadline, your application is automatically deemed complete.
- Resubmittal protection: When you resubmit, cities can only review items they flagged in the original incompleteness determination — no new objections allowed.
- Right to appeal: If a city issues an incompleteness determination or denial, applicants now have a formal statutory right to appeal to the local planning commission or governing body, with a written decision required within 60 business days.
- 60-day deemed approved: If a city fails to approve or deny within 60 days of a complete application, the ADU is deemed approved.
Size & Fee Changes
- Interior livable space definition: All ADU/JADU size limits now refer to interior livable space only — wall thickness, attic areas, and exterior dimensions are excluded. An 800 sq ft ADU means 800 sq ft of actual livable interior space.
- School fee exemption: ADUs and JADUs with less than 500 sq ft of interior livable space are exempt from school impact fees
- Impact fees: ADUs under 750 sq ft remain fully exempt from development impact fees
- JADU ordinance oversight: HCD now reviews JADU ordinances the same way it reviews ADU ordinances — cities must submit within 60 days of adoption or the ordinance is void
- Fire sprinklers: JADUs follow the same fire sprinkler rules as ADUs — not required if the primary home doesn't require them
- Legislative intent updated to explicitly state local ordinances cannot "unreasonably restrict" ADU and JADU construction
🔑 Breakthrough: Up to 3 ADUs + JADU on One Single-Family Lot
SB 543 amended Government Code section 66323 to explicitly state that cities must ministerially approve ADUs from section 66323 in combination with units approved under section 66314. HCD confirmed this in technical assistance letters to Solana Beach (December 2025) and Sacramento (January 2026), ordering both cities to update their ordinances accordingly.
How the 66314 + 66323 Combination Works
Previously, homeowners were limited to combinations within section 66323 only. Now both sections stack:
- Unit 1 (via 66314): Full-size ADU built to local development standards — no 800 sq ft cap. Can be attached, detached, or a conversion.
- Unit 2 (via 66323): ADU converted from an existing structure (garage, basement, barn, etc.)
- Unit 3 (via 66323): New construction detached ADU, up to 800 sq ft
- Unit 4 (via 66323): JADU within the primary home, up to 500 sq ft
Important Caveats
- Order matters: Obtain the 66314 permit first — using 66323 units first and hitting your FAR limit could block the 66314 permit later
- Not every homeowner will qualify for a 66314 permit — cities can still deny them. In that case, you're limited to 66323 combinations.
- Building 3–4 units on a single-family lot has serious implications for future mortgage eligibility and potential tax liability. Consult a lender, real estate attorney, and tax advisor before proceeding.
This is the most significant single-family ADU development since the 2020 reforms. Even homeowners who don't want 4 units benefit — it opens the door to building 2 smaller units instead of 1 large one, which can have real advantages for fees, flexibility, and future resale.
AB 462
Coastal / Disaster✓ In Effect
60-Day Coastal ADU Permits + Certificate of Occupancy Exception for Disaster Zones
Requires coastal development permits for ADUs to be approved or denied within 60 days — matching the inland standard. Also allows ADUs in disaster-declared areas to receive a Certificate of Occupancy before the primary home is rebuilt, enabling immediate occupancy while reconstruction is underway.
Coastal Permit Streamlining
- Local agencies with a certified Local Coastal Program must approve or deny ADU coastal development permits within 60 days of a complete application
- Coastal Commission appeals are eliminated for ADUs — local decisions are final
- Failure to act within 60 days = ADU is automatically deemed approved
- In LA County: ADUs in the coastal zone are fully exempt from needing a CDP in most cases
Disaster Zone Certificate of Occupancy Exception
An ADU can receive a Certificate of Occupancy before the primary home if all three conditions are met:
- The governor declared a state of emergency in that county after February 1, 2025
- The primary home was substantially damaged or destroyed by the emergency event
- The ADU has received construction permits and passed all required inspections
Directly relevant for homeowners rebuilding in Pacific Palisades, Altadena, Malibu, and other LA fire-affected areas. An ADU can now receive its own CofO first — allowing family to live on-site while the primary home is reconstructed. For coastal properties broadly, this ends years of CDP delays and appeals that could stretch 6–18 months.
AB 1154
JADU / Owner Occupancy✓ In Effect
JADU Owner-Occupancy Only Applies When Sharing a Bathroom — Plus Short-Term Rental Ban
If a JADU has its own separate bathroom, the property owner is no longer required to live on-site. All JADUs are now banned from short-term rentals of less than 30 days, regardless of bathroom configuration.
Key Provisions
- Owner-occupancy is now only required for JADUs that share sanitation facilities (a bathroom) with the primary home
- A JADU with its own separate bathroom = no owner-occupancy requirement
- All JADUs must be rented for terms of 30 days or longer — Airbnb-style short-term rentals are prohibited regardless of ownership situation
- JADUs are defined as dwelling units of up to 500 sq ft created within the existing primary home
Including a private bathroom in any JADU conversion is now strongly advisable. It makes the unit more livable, more rentable, and eliminates the owner-occupancy restriction entirely. The 30-day minimum rental term is a firm statewide floor for all JADUs.
SB 9 (2025)
HCD Enforcement✓ In Effect
Local ADU Ordinances Are Null & Void If Not Filed With HCD on Time
A city's ADU ordinance is automatically void if not submitted to HCD within 60 days of adoption. If a city ignores HCD noncompliance findings for 30 days, the ordinance is also void. The city then defaults to state-level ADU standards — which are typically more permissive.
Key Provisions
- Cities must submit new or amended ADU ordinances to HCD within 60 days of adoption
- Failure to submit = ordinance is null and void by operation of law
- If HCD finds noncompliance and the city doesn't respond within 30 days = ordinance is also void
- When a local ordinance is void, state ADU law automatically governs — which is typically more permissive than local rules
- Persistent noncompliance can be referred to the California Attorney General's office
Powerful tool when a city is being unreasonably restrictive. Their local ordinance may technically be void if they haven't complied with HCD submission requirements. Homeowners can request technical assistance through HCD to compel compliance. Important: SB 9 (2025) is a completely separate law from SB 9 (2021), which is the lot-splitting bill.
New
AB 1061
Historic Districts / SB 9✓ In Effect
SB 9 Lot Splits & Duplexes Now Allowed in Most Historic Districts
Narrows the historic district exclusion under SB 9. Previously, any property located within a historic district was fully blocked from SB 9 lot splits and duplexes. Now, only properties with a "contributing structure" (one that defines the district's historic character) are excluded — opening up SB 9 for thousands of previously blocked properties.
The Problem This Solved
Cities were designating large areas — sometimes entire cities — as "historic districts" specifically to block SB 9 lot splits and duplexes. This loophole rendered SB 9 largely useless in some jurisdictions. AB 1061 closes that loophole by narrowing the exclusion to only properties that actually contribute to a district's historic character.
The New Rule
- Still excluded from SB 9: Properties with a "contributing structure" — meaning a building that was constructed during the district's period of significance, retains historic integrity, and contributes to the historical, architectural, or cultural character of the district
- Now eligible for SB 9: Properties located within a historic district that do NOT have a contributing structure — even if the surrounding area is designated historic
- A property listed on the State Historic Resources Inventory or designated as a local landmark is still excluded regardless
- SB 9 projects in historic districts cannot alter or demolish any existing historic structure
Examples of Affected Districts
Some of the larger historic districts where this opens up eligibility: Old Pasadena Historic District, Main Street Historic District in Redwood City, and numerous districts within San Francisco and other major cities.
If a client was previously told their property is in a historic district and therefore can't do a lot split or duplex under SB 9, that answer may have changed on January 1, 2026. The key question now is whether there is a "contributing structure" on the specific parcel — not whether the surrounding area is a historic district.
📄 Official Bill Text ↗
New
AB 712
Enforcement / Penalties✓ In Effect
Cities Face Major Fines & Must Pay Attorney Fees for Violating Housing Laws
Courts must now award attorney's fees to homeowners and developers who successfully sue a city to enforce any housing law — including ADU laws. Cities also face fines of $10,000 per unit (minimum $50,000 per violation) if they violate housing laws after being warned by HCD or the Attorney General. Repeat violations multiply by five.
Key Provisions
- Mandatory attorney's fees: Courts must award reasonable attorney's fees to any homeowner or developer who wins a lawsuit to enforce a "housing reform law" — including ADU laws, the Housing Accountability Act, SB 330, density bonus law, SB 79, and streamlining laws. This is a major change — previously, only HAA violations reliably triggered fee awards.
- Per-unit fines: $10,000 per housing unit — or a minimum $50,000 per violation for projects with 4 or fewer units — when a city violates housing law after being warned in writing by HCD or the AG and given 60 days to correct the issue
- Repeat violation multiplier: If the same city violates the same statute more than once in the same housing element cycle, the court must multiply the fine by five
- Indemnity abuse prohibited: Cities can no longer require homeowners to indemnify the city for costs related to enforcement actions the homeowner themselves brings against the city
This fundamentally changes the economics of fighting a city that improperly denies or delays an ADU. Previously, suing a city was expensive and uncertain even if you were clearly in the right. With mandatory attorney's fees and escalating per-unit fines now in place, cities have much stronger financial incentive to comply with ADU law from the start. If you believe a city is improperly blocking your ADU, document everything in writing — this creates the paper trail HCD needs to issue a formal warning, which triggers AB 712's penalties.
📄 Official Bill Text ↗
New
AB 1308
Inspections / Permitting✓ In Effect
Final ADU Inspections Must Be Completed Within 10 Business Days
Building departments must complete final inspections within 10 business days of being notified that permitted construction is finished. Applies to residential projects of 10 or fewer units under 40 feet — which covers virtually every ADU. Missing this deadline is now a Housing Accountability Act violation, triggering AB 712's fines and attorney fees.
Key Provisions
- Building departments must complete final inspections within 10 business days after being notified that permitted work is complete
- Applies to new residential projects of 10 or fewer units that are no taller than 40 feet — this covers essentially every ADU project in California
- Also applies to additions to existing residential buildings with 9 or fewer units, where the addition contains 10 or fewer units
- HAA violation: Missing the 10-day inspection deadline is classified as a Housing Accountability Act violation — meaning it triggers attorney fee awards under AB 712 and potential fines if the city was previously warned
One of the most frustrating final steps in any ADU project has been waiting weeks — sometimes months — for a building inspector to schedule a final inspection. AB 1308 puts a hard 10-business-day ceiling on that wait. If a department misses this deadline, they're now in HAA territory, which carries real financial consequences under AB 712.
📄 Official Bill Text ↗
New
SB 625
Disaster Rebuild / HOA✓ In Effect
Disaster Rebuild Protections: HOAs Cannot Block Reconstruction — Streamlined Approval Required
Creates a ministerial approval process for rebuilding homes damaged or destroyed in declared disasters. HOAs cannot enforce any CC&R provision that blocks substantially similar reconstruction of a disaster-destroyed home (up to 110% of original interior square footage). Courts award attorney's fees to homeowners who win enforcement actions against non-compliant HOAs or local agencies.
HOA Protections (Civil Code 4752)
- HOA CC&Rs and governing documents that prohibit — directly or indirectly — the substantially similar reconstruction of a disaster-destroyed residential structure are void and unenforceable
- "Substantially similar" is defined using objective limits: up to 110% of the original interior livable square footage and height
- Courts must award attorney's fees to homeowners who prevail in enforcement actions against non-compliant HOAs
HOA Process Requirements (Civil Code 4766)
- HOAs must follow a streamlined review process for disaster rebuild applications, including written completeness determinations, fixed review timelines, and a formal appeal process
- Attorney's fees are awarded to homeowners who prevail in any enforcement action
Local Agency Streamlining
- Creates a ministerial (no discretion, no public hearings) approval process for rebuilding residential structures substantially damaged or destroyed in a disaster
- Includes fixed completeness review timelines
- Local agencies cannot prevent property owners from living in a mobile home or temporary structure on their property for up to 3 years following a disaster while rebuilding
Highly relevant for clients in the LA fire footprint — Pacific Palisades, Altadena, Malibu, and other affected communities. Both HOA and city approval processes for rebuilding are now streamlined and legally protected. Combined with AB 462's CofO exception for ADUs in disaster areas, homeowners have a clear legal path to rebuild and house themselves on-site during reconstruction.
📄 Official Bill Text ↗
New
AB 253
Permitting / Plan Check✓ In Effect
Stuck in a Slow City? You Can Now Hire a Private Plan Checker
If a city's estimated plan review time exceeds 30 business days — or the review hasn't been completed within 30 days — applicants for small residential projects (including ADUs) can now hire a state-certified private plan checker at their own expense. Once the private checker certifies compliance, the city must issue the permit within 10 days or provide specific written noncompliance reasons.
How It Works
- Applicant can retain a private plan checker if: (1) the city's estimated review time exceeds 30 business days, OR (2) 30 business days have passed without a completed review
- The private plan checker must be a state-certified professional — not just any contractor
- Cost is borne by the applicant
- Once the private plan checker certifies that the plans comply with applicable codes, the city has 10 business days to either issue the permit or provide a specific written statement of noncompliance
- If the city does not respond within 10 business days = permit is deemed approved
This is a significant new tool for homeowners stuck in jurisdictions with notoriously slow plan check departments. Cities like Los Angeles have historically had plan check backlogs stretching months. Rather than waiting indefinitely, you can now hire a private reviewer and force a decision. The permit-deemed-approved outcome if the city doesn't respond in 10 days has real teeth.
📄 Official Bill Text ↗
2024–2025 — Multi-Family Expansion, Amnesty & Coastal3 bills
SB 1211
Multi-Family✓ In Effect
Multi-Family Properties: Up to 8 Detached ADUs Per Lot
Dramatically expanded ADU rights for apartment and multi-family property owners — up to 8 detached ADUs per lot (not to exceed the number of existing units). No replacement parking required when converting uncovered parking spaces. "Livable space" formally defined for all ADU size calculations.
Key Provisions
- Multi-family property owners can now build up to 8 detached ADUs on their lot (previously the cap was 2)
- Number of new ADUs cannot exceed the number of existing residential units on the property
- Converting uncovered parking spaces to build ADUs no longer requires replacement parking — previously only covered structures (garages, carports) were exempt
- Local agencies cannot impose design or development standards beyond what state law explicitly permits
- ADU size limits clarified to refer to "livable space" — building on what SB 543 would later codify
A 6-unit apartment building can potentially add 6 more ADUs in its existing parking lot. This is one of the most underutilized opportunities in California real estate right now — most multi-family owners are unaware of it. The conversion of uncovered parking spaces (not just garages) is the key new right that SB 1211 added over prior law.
📄 Official Bill Text ↗
AB 2533
Amnesty / Legalization✓ In Effect
Legalize Unpermitted ADUs Built Before 2020 — Without Penalties
Expanded California's amnesty program: unpermitted ADUs built before January 1, 2020 can be permitted without penalties or full code compliance requirements. Only health and safety standards must be met. No extra fees or penalties allowed. A confidential pre-inspection option protects homeowners before they formally apply.
Key Provisions
- Applies to unpermitted ADUs built before January 1, 2020
- Cities cannot deny permit applications solely because the unit was built without permits
- Only needs to meet health and safety standards — full modern building code compliance is not required
- No penalties or additional fees may be charged
- Confidential pre-inspection: Homeowners can hire a licensed contractor to inspect the unit before formally applying — without triggering code enforcement action. This lets you understand what fixes are needed before committing to the process.
Homeowners with an unpermitted garage conversion or backyard cottage can now legalize it — which means they can include it in rental income calculations for financing purposes, add it to the appraised home value, and rent it legally. The confidential pre-inspection option significantly reduces the risk of starting this process. Very common situation in LA, the Bay Area, and San Diego.
📖 Maxable Deep Dive ↗
SB 1077
Coastal Zone⏳ Jul 2026 Deadline
Coastal Commission Must Publish ADU Guidance for Coastal Cities by July 2026
Required the California Coastal Commission and HCD to jointly develop and publish clear guidance for coastal cities on how to update their Local Coastal Programs to streamline ADU and JADU approvals. Published guidance due July 1, 2026.
Context
Building ADUs in California's coastal zones (Malibu, Santa Monica, Venice, Laguna Beach, Coronado, and other coastal communities) has historically been significantly more complicated due to California Coastal Act requirements. SB 1077 requires the Coastal Commission to publish clear guidance for these cities before July 1, 2026. At least one public workshop must be held before the guidance is finalized. AB 462 (2025) has already added 60-day permit timelines for coastal ADUs — SB 1077 will build on that.
For clients in coastal communities: the process is actively improving. AB 462 already created faster timelines and eliminated Coastal Commission appeals. The broader SB 1077 guidance (due July 2026) will provide cities with a clear roadmap to further streamline their processes. Now is a good time to begin planning a coastal ADU project — the regulatory environment has improved dramatically since 2024.
2023–2024 — Condo Sales, Pre-Approved Plans & Ownership Rules5 bills
AB 1033
Condo Sales✓ In Effect
ADUs Can Be Sold Separately from the Primary Home
Opened the door for ADUs to be sold as individually owned units, separate from the primary residence — similar to a condo. Cities must opt in by passing a local ordinance. Currently adopted by San Jose, Santa Monica, San Diego, and select other cities.
Key Provisions
- ADUs can be sold as separate legal units — but only in cities that have passed a local enabling ordinance
- Requires converting the property to a condominium: involves attorneys, surveyors, CC&Rs, a condo plat map, and California Department of Real Estate approval
- Existing mortgage lender approval is required if there's a mortgage on the property
- The ADU and primary home would each have separate titles, HOA-style governing documents, and separately financed/insured
Exciting in concept, but the condo conversion process is expensive and time-consuming — typically $30,000–$60,000+ in professional fees and several months of process. Most applicable to investors in cities that have already adopted local ordinances. This will become more practical as more cities opt in and the market matures.
AB 976
Owner Occupancy✓ In Effect
Owner-Occupancy for ADUs Permanently Eliminated
Permanently prohibited cities from requiring property owners to live on-site as a condition of having a standard ADU. Removed the 2025 sunset date that would have allowed cities to reimpose owner-occupancy restrictions in the future.
Key Provisions
- Cities permanently cannot require owner-occupancy for standard ADUs — no future sunset date
- Owner-occupancy requirements for JADUs depend on whether the JADU has its own bathroom — see AB 1154 (2025)
- Cities can still prohibit short-term rentals (under 30 days) for both ADUs and JADUs
Property owners can now rent out both the primary home and the ADU without living on-site — permanently. This is one of the most important laws for investor clients who want to purchase a property specifically to rent out both units.
AB 434 / AB 1332
Pre-Approved Plans✓ In Effect
All Cities Must Offer Pre-Approved ADU Plans Online
Required all California cities and counties to establish programs for pre-approving ADU plans and publishing them on their websites. Cities with 200,000+ residents faced a hard January 1, 2025 deadline. Also increased the maximum ADU height to 25 feet in some cases and relaxed setback requirements for pre-approved plans.
Key Provisions
- Every California city must accept submissions for pre-approval and publish approved plans on their website
- Height limits for detached ADUs increased to up to 25 feet in certain situations (up from 16 feet in some areas)
- Pre-approved plans may still require property-specific modifications for site conditions
- Architects retain ownership of their pre-approved designs — users typically pay a licensing fee
- Pre-approved plans can move through plan check significantly faster since structure-level review is already done
LA, San Jose, and San Diego have robust pre-approved plan libraries online. Smaller cities may have minimal options. Always check the specific city's website before estimating timelines based on pre-approved plans — quality and selection vary widely. The 25-foot height allowance is worth flagging for clients who want a 2-story ADU.
AB 916
Bedroom Conversion✓ In Effect
No Public Hearing Required to Add Bedrooms Within an Existing Home
Prohibited cities from requiring a public hearing to add bedrooms within an existing residential structure — enabling garage, attic, and basement conversions to bedrooms without the costly and time-consuming public hearing process.
Helpful for homeowners looking to expand interior square footage — for example, converting an attached garage to living space before adding a JADU within the home. Removing the public hearing requirement was a meaningful reduction in friction and cost for interior conversions.
AB 1661
Utilities✓ In Effect
ADUs Exempt from Individual Utility Meter Requirement
Exempted ADUs from the prior law requiring all residential units to have their own individual utility meters. ADU electrical and gas service can run through the primary home's existing meters — saving several thousand dollars in installation costs.
Reduces upfront ADU construction costs by eliminating the need to pay utilities to install a new meter — typically $3,000–$10,000+ depending on the utility and location. Property owners can still choose to install a sub-meter if they want to separately bill ADU tenants for utilities.
2021–2022 — Lot Splitting, Multi-Family & Key Cleanups4 bills
SB 9 (2021)
Lot Splitting✓ In Effect
Lot Splitting + Two-Unit Development on Single-Family Lots
Allowed single-family lots to be split into two separate parcels, or permitted a second home to be added as a duplex. When combined with ADU rights, a single formerly single-family lot can support 3–4 total units. AB 1061 (2025) expanded this to most historic districts.
Key Provisions
- A single-family lot can be split into two parcels — each parcel can then have its own primary dwelling
- Two-unit development option: a second dwelling can be added on the same lot (creating a duplex) without splitting
- Adding a second unit does NOT eliminate ADU rights — enabling 3–4 total units on the lot
- Each resulting parcel from a lot split must be at least 1,200 sq ft
- Owner-occupancy (in one of the units) is required for at least 3 years following a lot split — applicants must sign a notarized affidavit
- Properties in high fire hazard zones, flood zones, or wetlands are excluded
- As of Jan 1, 2026: most properties within historic districts are now eligible — see AB 1061
Homeowners with larger lots can split the parcel, sell one half, and use the proceeds to fund ADU construction on the remaining lot. This is one of the most powerful wealth-building tools available under California law. Important: SB 9 (2021) is the lot-splitting law. SB 9 (2025) is a completely separate and unrelated bill about HCD enforcement.
SB 10
Zoning✓ In Effect
Cities May Voluntarily Upzone Near Transit to Allow Up to 10 Units
Gave cities the optional ability to upzone parcels near major transit corridors to allow up to 10 residential units per parcel, bypassing CEQA environmental review. Unlike SB 79 (2025), this is voluntary — cities are not required to use it.
Key Provisions
- Optional for cities — they are not required to implement it (contrast with SB 79 which is mandatory)
- Must apply to parcels in a "transit-rich area" or "urban infill site"
- Exempt from very high fire hazard severity zones
- No CEQA environmental review required for qualifying upzones
Several cities have used SB 10 to voluntarily increase density near transit. If your client's property is near a transit corridor, check whether the local city has adopted an SB 10 upzone — it could significantly expand development options beyond what standard ADU law allows.
AB 2221 / AB 221
Cleanup✓ In Effect
Cleanup: 60-Day Rule Covers All Agencies Including Utilities — Multi-Family Concurrent Builds Allowed
Expanded the 60-day permit deadline to every agency involved in the review process — including utilities and water districts, not just planning departments. Also enabled ADUs to be built concurrently with new multi-family development projects, and clarified front setback exemptions.
Key Provisions
- The 60-day permit approval clock applies to ALL agencies in the review — including water districts, utility companies, and other reviewing entities, not just the planning department
- Front setbacks cannot prevent an ADU under 800 sq ft from being built
- Developers can build ADUs concurrently within new multi-family development projects, without needing to complete the primary building first
If a utility or water district is causing permit delays beyond 60 days, they are subject to the same 60-day rule as the planning department. Citing AB 2221 when escalating with utility agencies often resolves delays quickly — this is a tool most homeowners don't know they have.
SB 897
Cleanup / Sprinklers✓ In Effect
No Fire Sprinkler Retrofits Required — Unpermitted Work No Longer Blocks ADU Permits
Eliminated the requirement to retrofit fire sprinklers in the primary home when adding an ADU. Allowed ADU permits to proceed even when unpermitted work exists on the property — as long as it's not an active health or safety hazard. Required the state to establish an ADU grant program.
Key Provisions
- Adding an ADU does NOT trigger a requirement to retrofit fire sprinklers into the primary home
- Existing unpermitted work on a property does not block an ADU permit — unless it presents an active health or safety hazard
- Cities cannot withhold demolition permits on a property simply because an ADU permit has been issued there
- Required the state to establish a grant program to fund ADU and JADU construction (in addition to the CalHFA ADU grant that was already in place)
Prior to SB 897, cities were using the fire sprinkler retrofit requirement as an effective tool to block or significantly raise the cost of ADU approvals — sometimes adding $20,000–$50,000+ to a project. SB 897 removed that tactic entirely. The unpermitted work provision also removes a major hurdle for older properties where some work was done without permits over the years.
2020 — The Foundational Reform Wave5 bills
AB 68
Lot Rules✓ In Effect
ADU & JADU Allowed on All Single-Family Lots — No Minimum Lot Size
Allowed homeowners to build one ADU and one JADU on any single-family residential lot. Eliminated minimum lot size requirements statewide and removed the requirement to replace off-street parking when a garage is converted to an ADU.
Key Provisions
- No minimum lot size required to build an ADU
- One ADU and one JADU can coexist on any single-family lot
- No replacement parking required when converting a garage to an ADU
Before 2020, homeowners were frequently told their lot was "too small" to build an ADU. That restriction was eliminated by AB 68 — nearly every single-family property in California is now eligible to build at least one ADU and one JADU.
AB 881
Setbacks✓ In Effect
4-Foot Setback Standard Established — HOAs Cannot Prohibit ADUs
Established 4-foot side and rear setbacks as the statewide ADU standard. Front setbacks cannot prevent construction of an ADU up to 800 sq ft. HOAs cannot prohibit ADU construction — state law overrides CC&Rs.
Key Provisions
- 4-foot side and rear setbacks are the statewide standard — cities cannot require more for ADUs
- Front setbacks cannot block an ADU up to 800 sq ft, regardless of local front setback requirements
- No minimum lot size requirement
- HOAs cannot prohibit ADU construction — state ADU law supersedes HOA CC&Rs and governing documents
Every California property has the right to build at least an 800 sq ft ADU, regardless of lot size or setback restrictions. For HOA communities: while HOAs cannot prohibit construction, they can still enforce reasonable and objective design and aesthetic standards — as long as those standards don't effectively prevent the ADU from being built at all.
SB 13
Fees & Permits✓ In Effect
Impact Fees Waived for Small ADUs — 60-Day Permit Deadline Established
Cut permit approval from 120 to 60 days. Waived all impact fees for ADUs under 750 sq ft. Fees for larger ADUs must be proportional to the ADU's size relative to the primary home — not charged at the same rate as a full primary home. Eliminated the prior 5-year owner-occupancy requirement.
Key Provisions
- ADU permit approval required within 60 days of complete application (down from 120 days)
- Impact fees completely waived for ADUs under 750 sq ft of livable space
- Impact fees for larger ADUs must be proportional to the ADU's size relative to the primary dwelling — not a flat fee
- Prior 5-year owner-occupancy requirement eliminated
The 60-day permit clock is one of the most actionable rights homeowners have. If a city exceeds this timeline, they are non-compliant with state law. HCD has enforcement authority — and AB 712 (2025) now adds significant financial penalties for cities that violate these timelines after being warned.
AB 671
Financing✓ In Effect
State Must Publish a List of All ADU Grants & Financial Incentives
Required HCD to maintain and publicly publish a comprehensive, up-to-date list of all state grants and financial incentives available for ADU construction — particularly programs aimed at homeowners who will offer affordable rents.
HCD maintains this list at hcd.ca.gov. Check there for the most current list of available financing programs, including the CalHFA ADU grant program and any locally administered incentive programs in your area.
AB 3182
HOA✓ In Effect
HOAs Cannot Prohibit ADU Construction
Explicitly prohibited homeowners associations from banning or unreasonably restricting ADU construction on member properties. State ADU law takes precedence over HOA CC&Rs and governing documents. HOAs later received further restrictions under SB 625 (2025) for disaster reconstruction.
Key Provisions
- HOA CC&Rs and governing documents that ban or effectively prohibit ADU construction are void and unenforceable
- State ADU law supersedes HOA rules
- HOAs can still enforce objective, reasonable design and aesthetic standards — such as color palette, exterior finish materials, or roof pitch requirements
- However, those HOA aesthetic standards cannot be so restrictive that they effectively prevent ADU construction
Many homeowners in gated or planned communities believe their HOA prevents them from building. Under AB 3182, any outright HOA ban on ADU construction is unenforceable under state law. If your HOA is citing their CC&Rs to block an ADU, request a written explanation — and consult with a real estate attorney if needed, as the HOA may be liable for costs if they improperly block a lawful ADU.