FREE SB-9 SCREENING

SB-9 Lot Split Checker

See whether your Bay Area parcel looks like a candidate for an SB-9 urban lot split, and what the two resulting lots would measure.

Screen Your Lot First

SB-9 lets some Bay Area homeowners divide a single-family lot into two parcels. Many parcels are ruled out by a single condition: a tenant in the last three years, a historic designation, or a lot that is simply too small to divide. Answer five questions and see where yours stands before you pay for a survey.

Total lot size (sq ft)

Current zoning

How would you divide the lot?

Check anything that applies to your property

In a designated historic district, or a landmark property This parcel was already created by a previous SB-9 split You or an immediate family member already SB-9 split an adjoining parcel A tenant has occupied the property at any point in the last 3 years A unit on the site is rent controlled or has a recorded affordability restriction The plan would demolish or alter more than 25% of the existing exterior walls In a very high fire severity zone, floodway, wetland, prime farmland or conservation easement

Will you occupy one of the resulting lots as your primary residence for at least 3 years?

This is a preliminary screening based only on what you entered. It is not a determination and it is not legal advice. SB-9 is administered by your city or county, which applies its own objective development standards; local rules vary across the Bay Area and parts of the law have been challenged in court, so the state rules are not the complete picture. The final determination rests with that jurisdiction. Confirm your parcel with your local planning department, and book a free consultation with 9Builders to talk through what your lot can actually support.

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SB-9 Lot Split Questions

What Bay Area homeowners ask before they apply.

SB-9 lets an owner divide one qualifying single-family lot into two parcels of at least 1,200 sq ft each, and it allows up to two units on each resulting parcel. It does not override local rules. Cities and counties still apply their own objective standards for setbacks, height, and design, and they still review the application. Units created under SB-9 must also be rented for terms of at least 30 days.

A completed SB-9 lot split creates two legally separate parcels, so they can generally be sold separately once the parcel map is recorded and any conditions the jurisdiction attached have been satisfied. Timing and conditions vary by city, and the owner-occupancy affidavit can affect your plans. Confirm the details with your jurisdiction and a real estate attorney before you count on a sale.

To apply for an SB-9 lot split, the applicant signs an affidavit stating an intent to occupy one of the resulting parcels as a principal residence for at least three years after approval. It applies to lot splits, not to simply adding a second unit under SB-9. Cities enforce and document it differently, so ask your planning department how it is handled before you file.

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SB-9 Lot Split Checker

Screen Your Lot First

What we flagged

SB-9 Lot Split Questions

What does SB-9 actually allow, and what does it not?

Can I sell the two lots separately?

What does the 3-year owner-occupancy requirement mean in practice?

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