California legalized 700,000 homes. Year one built 53.

Yes. SB 9 applies statewide and is in force. The only ruling that ever limited it, an April 2024 decision exempting five charter cities, was reversed by the California Court of Appeal on November 12, 2025. The appellate court did not settle the underlying constitutional question; it sent the case back to the trial court to reconsider under the amended law (SB 450). So SB 9 is operative everywhere today, though a future trial-court ruling could reopen the charter-city issue.

Yes, if your lot is in a single-family residential zone and meets the conditions. A lot split must create two parcels, each at least 1,200 square feet, and neither parcel can be smaller than 40% of the original lot, so it is close to an even split. The split is approved ministerially, meaning at staff level without a discretionary hearing, as long as your plans meet the objective standards.

Up to four. SB 9 lets you put two units on a single-family lot, and separately lets you split the lot in two. Combine them, split the lot, then build two units on each of the two new parcels, and one original single-family lot becomes four homes. Many owners use only part of this, for example adding one unit without splitting, but four is the ceiling the law was designed around.

Only if you do a lot split. For a lot split you must sign an affidavit stating you will live in one of the units as your principal residence for at least three years from the date of approval. Community land trusts and qualified nonprofits are exempt. If you simply add a second unit without splitting the lot, there is no owner-occupancy requirement.

Yes. Big charter cities like Los Angeles and San Diego are covered. SB 450, in force since January 1, 2025, explicitly states SB 9 applies to charter cities, and the November 2025 appellate reversal removed the one court order that had carved out five of them. As of 2026 there is no charter-city exemption in effect, though the trial court could revisit the question on remand.

A city must approve or deny a complete SB 9 application within 60 days, or the application is deemed approved. This firm deadline came from SB 450 and took effect in 2025. It was added specifically because some cities were slow-walking or over-conditioning SB 9 projects, which was one reason so few got built in the early years.

Because legal permission did not overcome the economics. UC Berkeley’s Terner Center found that in SB 9’s first year, across 13 studied cities, only 53 units and 41 lot splits were approved, a tiny fraction of the 700,000 homes the law was modeled to make feasible. The barriers were high construction costs, most homeowners lacking the expertise or capital to act as builders, and many cities layering on local restrictions. In Los Angeles, the largest city, zero lot splits were approved in 2022.

Before SB 9 passed, the Terner Center estimated that more than 700,000 new homes would become newly feasible to build if the law took effect. That figure measured what became legally and financially possible on paper. The Center itself warned it was unlikely anywhere near that many would actually be built. The gap between that 700,000 and the few dozen units approved in year one is the central lesson of SB 9: feasibility is not production.

No. Qualifying SB 9 projects receive ministerial approval, which means a staff-level sign-off against objective standards, with no discretionary public hearing and no review under the California Environmental Quality Act. This was meant to make the path fast and predictable. In practice, some cities added their own objective standards that slowed projects, which SB 450 then reined in.

No. SB 9 cannot be used on a property that has had tenants at any time in the previous three years, and it is blocked for 15 years on properties where units were withdrawn from the rental market under the Ellis Act. These rules exist to stop the law from being used to displace existing renters, so it is aimed at owner-occupied and long-vacant single-family properties.

SB 9 excludes historic properties and historic districts, farmland, wetlands and conservation land, high fire-hazard zones, floodplains, hazardous-waste sites, and earthquake fault zones. It also cannot be used to remove rent-controlled or recently tenanted housing. If your property is in any of those categories, SB 9 will not apply even if it is zoned single-family.

No. SB 9 requires that any rental of the units be for terms longer than 30 days, which rules out short-term vacation rentals like Airbnb. The law was written to add long-term homes, not to expand the short-stay market, so a plan that depends on nightly rentals will not qualify.

Possibly, for charter cities. When the Court of Appeal reversed the 2024 ruling in November 2025, it did not decide whether SB 9 is constitutional. It sent the question back to the trial court to re-examine under the amended law. So a future trial-court decision could again find a problem for charter cities, and that could be appealed. For now, in 2026, SB 9 stands statewide, but the legal story is not fully closed.