SB 9 Lot Split in Los Angeles (2026 Rules)

An SB 9 lot split lets a homeowner in a single-family zone divide one lot into two. Then you can build up to two homes on each new lot. Approval is ministerial, which means no public hearing if the plan meets the rules. In Los Angeles in 2026, though, the process is harder than it sounds. The rules changed in 2025 and again on January 1, 2026. Some fire-damaged areas are also on hold, and the eligibility screen is strict.

This guide explains what SB 9 allows today and who qualifies. It also covers how the City of Los Angeles and LA County handle an SB 9 lot split, and when an ADU is the smarter move.

What SB 9 allows

California passed SB 9 in 2021 and has amended it since. It gives single-family lots two tools:

Two-unit development. You can build up to two main homes on one single-family lot, attached or detached. On a lot that has not been split, you can usually add ADUs as well.
Urban lot split. You can divide one lot into two parcels and build up to two homes on each. That allows up to four homes on the original property.

Overall, the key difference from an ADU is ownership. In most cities, you cannot sell an ADU apart from the main house. By contrast, each lot created by an SB 9 lot split can be sold on its own.

What changed in 2025 and 2026

SB 450, in effect since 2025

Cities must approve or deny a complete SB 9 application within 60 days.
Cities cannot apply stricter or less uniform standards to SB 9 projects than to other housing in the same zone.
Also, cities can deny a project only for specific health and safety impacts.
The old limit on tearing down more than 25 percent of a home’s outside walls no longer applies to two-unit projects.

AB 1061, in effect since January 1, 2026

Historic districts are no longer excluded across the board. In the City of Los Angeles, that includes Historic Preservation Overlay Zones. For example, a two-unit project can now move forward on a site with a non-contributing building. Likewise, a lot split can proceed if it does not touch a contributing building or any outside structural wall in the district. However, individually listed landmarks stay ineligible.

Palisades and Eaton fire areas

Meanwhile, Executive Order N-32-25 suspends SB 9 for certain sites. Specifically, it covers sites inside the Palisades or Eaton fire areas that also sit in a state Very High Fire Hazard Severity Zone. While the order is in effect, those lots cannot use SB 9.

Who qualifies for an SB 9 lot split

First, the lot must be zoned single-family and sit in an urban area. Then it has to pass a list of exclusions and tenant protections.

Site exclusions

Protected habitat, wetlands, conservation land and prime farmland.
Very High Fire Hazard Severity Zones, unless the project meets current fire safety and building codes. So many hillside lots can still qualify, except in the suspended fire areas above.
Earthquake fault zones and flood zones, unless the project meets seismic or flood rules.
Hazardous waste sites that the state has not cleared for housing.
Individually listed historic landmarks.

Tenant protections

You cannot demolish or alter a unit that a tenant lived in during the past three years.
You also cannot demolish or alter rent-stabilized or deed-restricted affordable units. In the City of Los Angeles, a pre-1978 property with two units can fall under rent stabilization.
Finally, a unit removed from the rental market under the Ellis Act in the past 15 years is off limits.

Lot split rules

Each new lot must be at least 1,200 square feet. In addition, neither lot can be smaller than 40 percent of the original.
You must sign an affidavit that you plan to live in one of the homes for at least three years after approval. Land trusts and qualified nonprofits are exempt.
You cannot split a lot that was already created by an SB 9 lot split. A city can also refuse a split if the same owner split a lot next door.
After a split, each new lot can hold two homes in total. ADUs and junior ADUs count toward that limit.

Standards cities can and cannot apply

Standard	What state law sets
Home size	Rules cannot block two homes of at least 800 sq ft each
Side and rear setbacks	Up to 4 feet; none for an existing building or a rebuild in the same footprint
Parking	Up to 1 space per home; none within a half mile walk of good transit or one block of a car share
Rentals	Must be longer than 30 days
Other zoning rules	Apply only if they do not block the two 800 sq ft homes
Building and fire codes	Apply in full

Still, on hillside lots in Los Angeles, building, grading and fire rules often decide what you can build long before zoning does. Our guide to building a fire-resistant home in Los Angeles covers what fire zone work adds.

How an SB 9 lot split works in Los Angeles

City of Los Angeles

Check eligibility on ZIMAS. Search your address, open Planning and Zoning, and view the SB 9 Eligibility checklist. It flags habitat, historic status and other screening items.
For two homes on one lot, you submit plans to LADBS for plan check and permits.
For a lot split, you file the parcel map with Los Angeles City Planning. The filing fee falls under Administrative Review, Major. The Bureau of Engineering also charges separate map fees, so check the city’s fee estimator for current amounts.
Sign the declarations. You confirm that the project will not demolish or alter protected housing. If you plan to tear down a home, you may also file a No Net Loss Declaration.
Record the map, then permit and build the homes.

The LADBS SB 9 page links the city’s memo, fact sheet and declaration forms.

Unincorporated LA County

In unincorporated areas, two-unit projects go through a ministerial site plan review with LA County Planning. A lot split also needs an approved and recorded parcel map. Eligible zones are R-1 and R-A, plus a few specific plan zones. Under current county guidance, the county also excludes lots in the coastal zone. That includes the Santa Monica Mountains coastal area.

Ventura County and Conejo Valley cities

Thousand Oaks, Simi Valley, Camarillo, Moorpark, Oxnard and other cities each have their own SB 9 rules and forms. The state framework is the same. Still, fees and design standards differ, so confirm local rules before you pay for design.

What an SB 9 lot split really costs

In practice, plan for two separate budgets: the split itself and the new home.

The split: a boundary and topo survey, a civil engineer for the parcel map, city fees, and title and recording costs. Utility separation can add a lot, because each lot needs its own sewer, water and power.
The new home: a new house costs about the same as any ground-up build. Our guide to new home construction cost in Los Angeles breaks down cost per square foot, design, permits and site work.

Then compare both budgets with what the new lot is worth before you commit. Early SB 9 data from UC Berkeley’s Terner Center showed that Los Angeles drew far more applications than any other city in the first year. Even so, approvals lagged, and many projects stalled at the planning stage.

SB 9 lot split or ADU?

For most Los Angeles homeowners, an ADU is still the faster and cheaper way to add a second home. ADU approvals are routine, the 60-day review is well tested, and you keep one lot and one mortgage. Our ADU permitting process guide shows how that path works.

On the other hand, an SB 9 lot split makes more sense when:

You want to sell or refinance part of the property on its own.
The lot is large and flat, with room for two homes and their own access.
You plan to live on site for at least three years.
Utilities can be split without a long or hard sewer run.

So the first step is a feasibility check. That means the ZIMAS screen, a look at slope and utilities, and a rough budget for the split and the build. In a few weeks, it tells you whether SB 9 is a real opportunity or a detour. If you are weighing a bigger main house instead, our guide to home additions in Los Angeles covers that option.

FAQ

Frequently Asked Questions

How small can an SB 9 lot split be?

Each new parcel must be at least 1,200 square feet, and neither parcel can be smaller than 40 percent of the original lot.

Do I have to live on the property after an SB 9 lot split?

Yes. The applicant must sign an affidavit stating they intend to live in one of the units as their principal residence for at least three years after the split is approved. Community land trusts and qualified nonprofits are exempt.

How many units can I build with an SB 9 lot split?

Up to two units on each new lot, for a maximum of four on the original property. After a split, ADUs and junior ADUs count toward the two-unit limit on each lot.

Is SB 9 allowed in the Palisades and Eaton fire areas?

Not right now for sites that are both inside those fire perimeters and in a state-identified Very High Fire Hazard Severity Zone. Executive Order N-32-25 suspends SB 9 for those properties.

How do I check if my Los Angeles property qualifies for SB 9?

Search your address on ZIMAS, open the Planning and Zoning section and view the SB 9 Eligibility checklist. It screens for habitat, historic status and other exclusions before you spend money on design.

Considering an SB 9 Lot Split in Los Angeles?

Send us your address and what you hope to build. We will review eligibility, topography and utilities with you and help you decide whether SB 9, an ADU or an addition is the better path.

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