Navigating the SB-9 lot split process can be complex, often requiring coordination with planning departments, engineers, and surveyors.
We are an LA-based land use consulting firm specializing in entitlements and permitting, helping property owners across Southern California move projects from concept through approval.
For homeowners considering an SB-9 lot split, we provide guidance to help determine the best path forward and move projects efficiently through review.
SB-9 was enacted as part of California’s broader response to the ongoing housing crisis, which has created a critical need for increased housing supply, particularly within single-family zones where development has historically been limited.
Under California Government Code, SB-9 allows qualifying homeowners to create additional housing opportunities by subdividing residential parcels and increasing density on eligible lots. The goal is to enable more housing in existing neighborhoods without requiring large-scale rezoning or discretionary approvals.
The law supports affordable housing production by unlocking underutilized land in established residential areas. By allowing lot splits and additional units on a single-family parcel, SB-9 creates more housing options while maintaining local zoning frameworks and reducing the need for infrastructure expansion.
An SB-9 lot split allows qualified homeowners to divide a single parcel of land into two separate lots. It comes from the SB-9, a state law that aims to create new housing opportunities on limited land.
In simple terms, you may be able to take one residential lot and legally separate it into two separate lots. Each new lot can then have its own residential home and supporting structure.
This doesn’t mean every property in California can be split.
The SB-9 only applies to qualifying single-family properties. SB-9 rules can’t be used on commercial lots. Moreover, each city reviews applications based on specific eligibility requirements.
At its core, the SB-9 allows homeowners on a single-family residential lot to do two things with their property.
First is what we call an urban lot split. You can divide one residential lot into two separate parts.
Second, you get the ability to build up to four structures on what was once a single-family property. Apart from two primary homes, you may also build accessory dwelling units (ADUs) or junior accessory dwelling units (JADUs).
The SB-9 lot split isn’t just a simple division of land. Properties must meet specific qualifying criteria and requirements before they can be approved.
Qualifying Criteria & Requirements
Process: SB-9 projects are reviewed through a ministerial process. This means cities evaluate applications based on objective zoning standards, rather than discretionary review or public hearings.
Restrictions
Location-Based Restrictions: The property must not be within protected environmental areas. You’re also not qualified if your property is considered a historic property, located within a historic district, or within a conservation zone.
One of the most important rules under SB-9 is the minimum lot size. Even if your property qualifies, the new parcels can’t be too small.
The SB-9 requires that the newly split lots must be roughly the same size. The split should be no smaller than 60/40.
Additionally, each resulting parcel must be at least 1,200 square feet in size. As a result, the original lot must typically be at least 2,400 square feet to support an SB-9 lot split.
In general, you can build up to four residential units under the SB-9 rules. These include the following.
Note that what you can build will vary depending on your actual lot size and local regulations. In many cases, site limitations and ADU/JADU rules can prevent you from building more than one primary home per lot.
An SB-9 lot split creates new opportunities for homeowners by increasing flexibility in how a residential property can be used and developed.
In general, the lot split process starts when you submit an SB-9 application to the local planning department. Examples of paperwork you need to submit include basic forms, property information, and supporting documents.
Next, the city reviews the application to confirm SB-9 eligibility. This may include evaluation of zoning, access, and environmental constraints. Applicants should be prepared to provide surveys, parcel maps, tree reports, and proof of legal street access.
Once the review is complete, the lot can be split through a ministerial process. After approval, the lot then becomes two separate legal properties.
The process of subdividing a lot under SB-9 rules can take approximately 7 to 12 months. The exact timeframe depends on your specific project.
If you require more permits, like design review or grading, the processing time will take longer. Moreover, you should also consider the time required for obtaining other permits.
In some cases, your property may need permits from the Department of Public Works or the Environmental Health Division.
It is critical to submit a complete application package at the outset, as incomplete submittals can result in delays, requests for additional information, or resubmittal requirements.
Whether you should pursue an SB-9 lot split or build an accessory dwelling unit (ADU) on your existing property depends on your goals and site conditions—there is no one-size-fits-all solution.
If your only goal is to add extra living space, then building an ADU is cheaper and more practical. You can still build another housing unit while keeping full control over your property.
An SB-9 lot split, on the other hand, provides greater long-term flexibility by creating two legal parcels and expanding future development potential. While the process is more complex, it can maximize the overall use and value of the property over time.
While the SB-9 can be advantageous for a lot of homeowners, not everyone qualifies. Below are some of the limitations of the SB-9.
No. An advantage of the SB-9 is that it uses a ministerial approval process.
If you meet the requirements, the city can approve your application without public hearings. You don’t need to deal with neighborhood votes or planning commission approvals.
Yes. You can legally sell a lot that has been subdivided through the SB-9. However, if your property currently has a loan, you must get your mortgage provider’s approval. You must obtain a partial release of the mortgage before you can legally sell one of the lots.
Navigating the SB-9 lot split process can be complicated. Even straightforward projects need careful coordination.
This is where we can help.
Pattern is an LA-based land use consulting firm that specializes in entitlements and permitting. We help property owners work through lengthy approval processes throughout Southern California.
Our team works directly with regulatory agencies to support efficient project delivery and ensure compliance throughout the entitlement process. For homeowners considering an SB-9 lot split, Pattern can assist with feasibility analysis, permitting strategy, and application support.
If you need guidance with your project, consider reaching out to Pattern. We’re here to help you determine the best path forward!
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