Lot splits under SB 9 in Santa Ana: the local rules

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

What Santa Ana's code says

Santa Ana code What Santa Ana's code adds
How the lot may be divided	Each new lot must be between 40% and 60% of the original lot's area. Applies: Applies to urban lot splits; the lot being split must be at least 2,400 square feet. § 41-2109 · code text Each of the resulting lots must be between forty (40) percent and sixty (60) percent of the original lot area.
Unit size	New primary homes: over 500 and at most 800 square feet; a smaller existing home may expand to 800. Applies: Applies to two-unit projects and to lots created by an urban lot split. § 41-2115 · code text A primary dwelling that was legally established prior to the two-unit project and that is smaller than eight hundred (800) square feet may be expanded to eight hundred (800) square feet after or as part of the two-unit project.
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. § 41-2109 · code text The resulting lots must each be at least one thousand two hundred (1,200) square feet.
Standards	Each lot needs at least 12.5 feet of street frontage; an easement serving up to 2 units: 12 feet minimum. Applies: Applies to access for lots in an urban lot split. § 41-2109 · code text Each resulting lot must have frontage on the public street right-of-way of at least twelve and one-half (12.5) feet. No more than 2 homes of any kind may be built on a lot created by an urban lot split. Applies: Applies to lots created by an urban lot split. § 41-2115 · code text No more than two (2) dwelling units of any kind may be built on a lot that results from an urban lot split. A two-unit project is allowed, plus any ADU or JADU that state law and the city's ADU ordinance require. Applies: Applies only to lots not created by an urban lot split. § 41-2115 · code text A lot that is not created by an urban lot split may have a two-unit project under this section, plus any ADU or JADU that must be allowed under state law and the city's ADU ordinance. Rooftop decks are not allowed on any new or remodeled home or structure. Applies: Applies to lots with a two-unit project. § 41-2115 · code text No rooftop deck is permitted on any new or remodeled dwelling or structure on a lot with a two-unit project. At most 25% of an existing home's outer walls may be demolished, unless tenant-free for the last 3 years. Applies: Applies to two-unit projects that demolish part of an existing home. § 41-2115 · code text The two-unit project may not involve the demolition of more than twenty-five (25) percent of the existing exterior walls of an existing dwelling unless the site has not been occupied by a tenant in the last three (3) years. Buildings may cover at most 35% of net lot area; 50% for new one-story buildings deed-restricted to stay one-story. Applies: Applies to two-unit projects, and only so far as it does not prevent 2 units of 800 square feet each. § 41-2115 · code text The maximum building coverage of net lot area shall be thirty-five (35) percent. If new structures are proposed to be one-story and be deed restricted to be maintained as one-story structures in perpetuity, a fifty (50) percent lot coverage is allowed.

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Frequently asked questions

Can I split my lot under SB 9 in Santa Ana?

Santa Ana's code: Each new lot must be at least 1,200 square feet. (Applies to each lot created by an urban lot split.) (§ 41-2109); New primary homes: over 500 and at most 800 square feet; a smaller existing home may expand to 800. (Applies to two-unit projects and to lots created by an urban lot split.) (§ 41-2115).

Lot splits under SB 9 in Santa Ana

What Santa Ana's code says

Who this affects

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