Lot splits under SB 9 in Rialto: the local rules

Each rule below links to the section of the Rialto Municipal Code it was read from, with the code text one click away (checked October 2026). General information, not legal advice.

What Rialto's code says

Rialto code What Rialto's code adds
How the lot may be divided	Each new lot must be between 40% and 60% of the original lot area. Applies: Applies to each lot created by an urban lot split. § 17.51.050 · code text Each lot created by an urban lot split shall be between forty percent and sixty percent of the original lot area.
Minimum new lot size	Each new lot must be at least 1,200 square feet. Applies: Applies to each lot created by an urban lot split. § 17.51.050 · code text Each lot created by an urban lot split shall be at least one thousand two hundred square feet in area.
Standards	Each new lot must adjoin a public street right-of-way. Applies: Applies to each lot created by an urban lot split. § 17.51.050 · code text Each lot created by an urban lot split shall adjoin a public street right-of-way. At least 24 feet of frontage on the public street. Applies: Applies to each lot created by an urban lot split. § 17.51.050 · code text Each lot created by an urban lot split shall have frontage on the public street right-of-way of at least twenty-four feet. No more than 2 dwelling units on each new lot. Applies: Applies to a lot created by an urban lot split. § 17.51.050 · code text No more than two dwelling units of any kind may be built on a lot that results from an urban lot split. The original lot must be at least 2,400 square feet. Applies: Applies to the lot to be split. § 17.51.050 · code text The lot to be split must be at least two thousand four hundred square feet in area. Only a lot in a single-family residential zone may be split. Applies: Applies to an urban lot split. § 17.51.050 · code text The lot to be split is in a single-family residential zone. No street dedication or offsite improvements are required. Applies: Applies to an urban lot split. § 17.51.050 · code text Notwithstanding Section 66411.1 of the SMA, no dedication of rights-of-way or construction of offsite improvements is required for an urban lot split.

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Frequently asked questions

Can I split my lot under SB 9 in Rialto?

New lots from an urban lot split must be 40% to 60% of the original lot area and at least 1,200 square feet.

Lot splits under SB 9 in Rialto

Key points

What Rialto's code says

Who this affects

Frequently asked questions

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