How to Legalize Your ADU with AB2533

Unpermitted ADUs are everywhere in California—and until recently, many homeowners didn’t have a clear or affordable path to fix them.

That’s where Assembly Bill 2533 (AB2533) comes in, offering a rare opportunity to legalize existing units without tearing them down, facing steep penalties, or navigating a maze of red tape.

If you’ve got a unit built before 2020 and you’re unsure how to make it compliant, this AB2533 guide will walk you through every step—backed by the expert insight of NEO Builders and Design, top-tier general contractors in Los Angeles specializing in ADU construction and design.

Known for being the fastest team in L.A. to get it done, they combine speed with quality to help homeowners legalize with confidence.

Understanding The Role of AB2533 in the California ADU Amnesty Program

What Is an ADU and Why Are They So Popular in California?

An Accessory Dwelling Unit (ADU) is a secondary housing unit located on the same lot as a primary residence. It can be detached (like a backyard cottage), attached (such as an addition), or converted from an existing space—most commonly a garage or basement.

In California ADU development has surged in popularity over the last several years, largely due to skyrocketing housing costs, a growing demand for rental housing, and the rise of multigenerational living. These small but functional units offer a creative solution to California’s housing shortage by adding livable square footage without expanding urban sprawl.

ADUs provide homeowners with flexibility, added property value, and—most importantly—a new stream of passive income.

With recent updates to California ADU regulations, these units are now faster, easier, and more affordable to build and legalize, especially with the support of experienced ADU contractors like NEO Builders.

Why Many Homeowners Built ADUs Without Permits

Strict zoning laws, high permitting fees, and inconsistent city rules once made legal ADU construction nearly impossible.

That’s why thousands of Californians built unpermitted ADUs—often unaware of the long-term risks, including citations (official notices of violation), legal liability, and even forced demolition. AB2533 was introduced as part of the California ADU Amnesty Program to help solve this exact problem.

AB2533 and the California ADU Amnesty Program: Why It Matters

The ADU amnesty program offers homeowners a streamlined path to bring unpermitted dwelling units up to code.

It prioritizes safety over complex administrative processes, allowing homeowners to legalize ADUs that meet basic habitability standards—even if they don’t comply with every aspect of current building codes.

Instead of requiring extensive retrofits or navigating layers of permitting procedures, the focus is on ensuring the unit is safe to live in.

It’s a win-win: cities get safer, more accountable housing, and property owners gain legal peace of mind.

The Key Legislation Behind AB2533 and ADU Legalization

How AB2533, SB 13, AB 68, and AB 881 Streamlined ADU Development

These new California ADU laws eliminated many of the local barriers that previously made building and legalizing accessory dwelling units nearly impossible.

Assembly Bill 2533 (AB2533), taking effect January 1, 2025, expands the California ADU Amnesty Program by including unpermitted ADUs and JADUs built between 2018 and 2020. It protects eligible homeowners from retroactive fees and encourages cities to focus on safety-based habitability standards rather than full modern code compliance. We break down exactly what AB2533 means—and which fees you can avoid—later in this guide.

Senate Bill 13 (SB 13), which took effect in January 2020, prohibited cities from requiring owner-occupancy for ADUs and Junior ADUs through 2025 and significantly reduced impact fees for smaller units.

Assembly Bill 68 (AB 68) required local agencies to approve ADUs within 60 days, allowed for multiple ADUs on a single lot, and banned cities from enforcing minimum lot size requirements.

Assembly Bill 881 (AB 881) clarified that local governments could not unreasonably restrict ADUs based on zoning, and reinforced that owner-occupancy requirements would be suspended. Together, these laws also limited cities’ ability to impose parking requirements, especially for ADUs near public transit or within existing structures.

These sweeping reforms paved the way for rapid ADU expansion and created the legal groundwork that AB2533 builds upon. If you’re curious about the statewide housing impact of these reforms, ADU amnesty reform provides helpful context.

For more on AB2533 and new ADU laws, check out: NEW ADU Laws in 2025 Are a GAME CHANGER

The Role of Health & Safety Code §17958.12

Health & Safety Code §17958.12 is one of the most important legal tools behind the Amnesty Program.

This section of the law gives local governments the authority to approve existing, unpermitted ADUs using “objective alternative standards”—even when those units don’t meet every element of today’s building codes.

The intent of this code is to prioritize health and safety while acknowledging that many older ADUs were built before the state reformed its ADU laws in 2020.

Instead of requiring homeowners to bring everything up to full modern code—which can be prohibitively expensive or even physically impossible—cities can now evaluate these units based on core habitability factors, like:

Adequate emergency exits and access
Safe electrical and plumbing systems
Structural soundness
Fire safety features (like smoke and carbon monoxide detectors)

This law is what allows cities to offer ADU amnesty in the first place. Without it, thousands of units would remain technically illegal, even if they were safe to live in.

By focusing on real-world livability over rigid compliance, §17958.12 has become the legal backbone of local ADU legalization efforts across California.

If you're a homeowner with an older unpermitted ADU, this law could be your pathway to full compliance—without having to tear out walls or rebuild from scratch.

ADU contractors like NEO Builders work directly with city inspectors to ensure units are evaluated fairly under this standard and upgraded only where truly necessary.

What AB2533 Means for Property Owners in 2025

Assembly Bill 2533 (AB2533), set to take effect on January 1, 2025, extends amnesty eligibility to cover unpermitted ADUs and JADUs constructed between 2018 and 2020.

This legislation allows eligible homeowners to legalize their units without facing retroactive impact fees, connection fees, or capacity charges—fees that cities often try to collect when bringing older units into compliance.

The bill also reinforces the use of simplified habitability standards, allowing cities to focus on health and safety rather than full modern code upgrades.

For homeowners who built ADUs during that time period, AB2533 is a game-changer, offering a realistic and affordable path to full accessory dwelling unit legalization.

Here’s a breakdown of the types of fees AB2533 helps homeowners avoid:

Impact Fees: These are fees cities typically charge developers to offset the strain that new housing puts on public infrastructure—such as roads, schools, parks, and emergency services. Even though unpermitted ADUs already exist, some cities have tried to apply these fees retroactively when homeowners seek to legalize them.
Connection Fees: These are charges for connecting an ADU to municipal water, sewer, or gas lines. In many cases, these fees are calculated the same way as for brand-new construction—even if the ADU was built years ago and already uses these utilities.
Capacity Charges: These fees are meant to account for the increased demand placed on public utility systems (like wastewater treatment facilities or power grids). Cities may attempt to apply these charges when legalizing older ADUs, especially if they weren't accounted for in planning models.

Thanks to AB2533, eligible homeowners are protected from these retroactive costs, which can sometimes total tens of thousands of dollars—making the legalization process far more affordable.

Who Qualifies for AB2533?

Eligibility Criteria Based on Construction Date

To qualify, your unpermitted ADU must have been built before January 1, 2020. Some cities align with the 2018–2020 window introduced by AB2533. Either way, proof of the construction date is crucial.

What Counts as Proof of an Existing ADU?

Acceptable documentation includes:

Old utility bills
Lease agreements
Construction receipts
Dated photos or satellite imagery
Property tax assessments

NEO Builders can help gather and present this information in a way that meets city requirements.

Differences Between ADUs and JADUs Under AB2533

A Junior ADU (JADU) is a smaller unit (under 500 sq ft) that shares amenities—such as a bathroom or kitchen—with the main home.

JADUs and standard ADUs are both eligible for legalization under AB2533 across California, though inspection and upgrade requirements may differ slightly.

Because JADUs are more compact and integrated into the primary residence, their documentation and compliance process may be less intensive.

That said, they still must meet essential habitability standards related to ventilation, safety, and electrical systems.

For homeowners, this means JADUs may be faster and more affordable to legalize—but working with experienced contractors like NEO Builders ensures the unit is properly categorized, compliant, and approved by local authorities.

Step-by-Step Guide to Legalizing Your ADU with AB2533

Initial Self-Assessment of Your Unit

Start by reviewing your ADU’s core safety features, including exits, smoke and carbon monoxide detectors, electrical panels, and ventilation.

If anything seems outdated, missing, or potentially unsafe, don’t wait—schedule a professional walkthrough with NEO Builders to identify exactly what’s needed for compliance.

Gathering and Submitting Required Documentation

Compile all evidence that shows your ADU existed before the program’s eligibility cutoff date.

This step is where many homeowners face delays, so accuracy and completeness are key. A knowledgeable contractor like NEO Builders can assist in preparing required documentation, including floor plans, system diagrams, and other materials that meet city submission standards.

Scheduling a Health and Safety Inspection

Local officials will inspect your ADU to identify any major safety concerns and ensure it meets basic habitability standards.

The goal of this inspection is not to penalize you—it’s to give you a clear roadmap for bringing your ADU up to legal and livable standards.

However, if inspectors find any life-threatening issues, such as exposed wiring or structural instability, those must be addressed immediately before moving forward.

Making Necessary Upgrades to Meet Habitability Standards

Common upgrades may include installing GFCI outlets, adding fire-rated doors, improving ventilation, updating smoke and carbon monoxide detectors, and repairing outdated plumbing or electrical systems.

All work must be completed by licensed professionals to meet local and state codes. NEO Builders works closely with homeowners to carry out these required upgrades, ensuring the ADU is safe, compliant, and ready for inspection without unnecessary delays.

Final Inspection and Receiving Your Certificate of Compliance

Once all required upgrades are completed, you’ll schedule a final inspection with your local building department.

If the unit passes, the city will issue a Certificate of Compliance—officially confirming that your ADU meets current health and safety standards.

From there, your ADU becomes fully legal, insurable, and eligible to generate rental income.

Common Challenges Homeowners Face When Legalizing Under AB2533

Missing Documentation or Unclear Construction Dates

This is one of the most common challenges homeowners face during the ADU legalization process.

If you don’t have physical proof of when your ADU was built, NEO Builders can help explore alternative verification methods—such as satellite imagery, dated photos, third-party affidavits, or past utility records—to support your case with the city.

Understanding Local Code Requirements

While California sets statewide guidelines for ADUs, local jurisdictions can—and do—adopt their own rules that add additional layers of regulation.

ADU requirements can vary significantly between cities like Los Angeles and Pasadena, and even within neighborhoods due to historic overlays, hillside zones, or specific plans.

That’s why working with a contractor who deeply understands local ADU regulations in California is essential to avoiding costly missteps and delays.

Budgeting for Modifications and Upgrades

Upgrade costs can range from a few thousand dollars to $30,000 or more, depending on the scope of work, the condition of the unit, and city-specific code requirements.

Always request a detailed scope of work and itemized budget estimate to avoid surprises. NEO Builders provides transparent, upfront pricing and will walk you through each required upgrade so you can plan with confidence.

Navigating Permits and Inspections Delays

City backlogs can stretch for months.

To stay ahead, submit applications early, track progress closely, and follow up frequently.

Partnering with an experienced contractor like NEO Builders can help streamline approvals, avoid common pitfalls, and keep your ADU legalization moving forward.

Benefits of Legalizing Your ADU With AB2533

Increased Property Value for Long-Term Wealth Building

Legal ADUs add verifiable square footage and rental potential to your property—both of which are major drivers of appraised value.

Buyers are far more willing to pay a premium for a unit that’s fully permitted and compliant.

For high-end homeowners, this means greater resale value and a stronger long-term return on investment.

Eligibility for Legal Rental Income

A permitted ADU can be leased without risk of legal pushback, helping offset your mortgage or fund home upgrades.

It also ensures compliance with California ADU regulations regarding tenant protections and rental duration.

Compliance with Lender and Insurance Requirements

Lenders and insurers typically exclude unpermitted dwelling units in Los Angeles and beyond from coverage or refinancing options.

Legalization turns your ADU into an insurable, financeable asset.

Protection from Fines and Legal Action

Legalizing your ADU under AB2533 can shield you from enforcement actions, such as daily fines or forced removal.

You get long-term peace of mind—and the freedom to use your space without fear.

City-by-City Variations in AB2533 Implementation

How the Process Differs in Los Angeles, Pasadena, and Culver City

Each city interprets and implements ADU amnesty slightly differently. For example:

Los Angeles allows alternative code compliance through LADBS (Los Angeles Department of Building and Safety), focusing on life safety over full modern code upgrades.
Pasadena requires detailed inspection reports as part of its legalization process, especially for units seeking financial assistance.
Culver City offers flexible conversion options but may require full architectural drawings, depending on the unit’s condition and layout.

Why It’s Important to Work With Local Experts in Your Area

Navigating AB2533 is much easier when you’re working with professionals who know your city’s process inside and out.

Contractors unfamiliar with local jurisdictions may overlook critical steps, slow down permitting, or cause unnecessary delays.

NEO Builders has worked in all major LA County cities and understands the specific permitting standards, documentation requirements, and inspection protocols each city enforces.

That local insight can make the difference between a stalled project and a fully legalized, rentable ADU.

What Happens If Your ADU Fails the Safety Inspection Under AB2533?

Correcting Life-Threatening Issues with Licensed Professionals

Cities cannot approve units with life-threatening issues like:

Structural failure
Exposed electrical wiring
Sewage backflow or leaks
Faulty gas lines

These must be addressed immediately.

Temporary fixes or DIY work won’t meet inspection standards. All repairs must be completed by licensed professionals who can document and certify the work.

NEO Builders offers full-service compliance support, from evaluating the issues to handling the upgrades and pulling permits.

Their team ensures your ADU meets the required standards—safely, quickly, and correctly—so you can move forward with legalization.

How Long Does the AB2533 ADU Legalization Process Take?

Timeline for Permit Review and Inspections

Expect 3–6 months from start to finish. This depends on your city’s workload and how quickly you gather documentation.

Average Time to Complete Upgrades

Minor fixes may take 1–2 weeks. Larger renovations can take 1–2 months, especially if structural changes are required.

Tips for Staying on Track and Avoiding Delays

Submit a complete application
Stay in touch with your city contact
Use one team for design, permitting, and building
Set a clear timeline with your contractor

Financial Considerations for ADU Legalization

Costs You Might Incur for Repairs and Permits

Depending on the condition of your ADU and your city’s specific requirements, here’s what you can expect to budget for:

Permits: $1,000–$8,500Permit costs vary by location, square footage, and project valuation. For example, in Los Angeles, converting a small garage might cost around $1,000 in permits, while a larger new construction ADU could run over $8,000.
Upgrades: $15,000–$30,000+Typical upgrades include electrical rewiring, plumbing updates, structural work, fire safety improvements, and GFCI outlet installations. The total depends on the current condition of your unit and the extent of work required to meet code.
Inspections: Usually included in city permit feesMost cities roll inspection costs into their overall permitting fees, so you likely won’t be billed separately—but always double-check with your local building department.

How NEO Builders Helps Homeowners Legalize Their ADU with AB2533

Seamless Legalization from Start to Finish

NEO Builders offers a true design-build experience. From initial assessment to completed construction, every step is managed in-house—ensuring speed, precision, and compliance without third-party delays.

Local Expertise, City by City

Whether you’re legalizing an unpermitted ADU in Los Angeles, Inglewood, or Burbank, NEO Builders knows the regulations, workflows, and city contacts that keep your project moving.

Trusted by High-End Homeowners

Affluent property owners choose NEO Builders for a reason: they prioritize discretion, design quality, and legal peace of mind.

The result? Beautiful, code-compliant ADUs delivered on time and with zero guesswork.

FAQs About AB2533 and ADU Legalization

What’s the deadline to apply for ADU legalization under AB2533?

Most cities require applications by the end of 2025, but timelines vary. Contact NEO Builders to confirm your city’s deadline.

Do I have to tear down my unpermitted ADU?

No—most units can be brought up to code with upgrades.

Will my property taxes increase after legalizing an ADU?

Possibly. Legalizing adds value, which may affect your assessment. However, increases are typically modest.

Can NEO Builders help me legalize my garage conversion?

Absolutely. Garage conversions are their specialty across Los Angeles County.

What cities does NEO Builders work in?

NEO Builders serves Los Angeles, Culver City, Thousand Oaks, San Fernando Valley, Burbank, Glendale, Altadena, Pasadena, and Inglewood.

Book a Free ADU Consultation with NEO Builders Today

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