San Diego County Supervisors Approve Ordinance Allowing Separate ADU Sales, Aligning Local Rules With State Law

Ordinance change opens a pathway for accessory units to be conveyed separately in unincorporated areas

The San Diego County Board of Supervisors voted unanimously on March 4, 2026, to approve an ordinance amendment designed to align county rules on accessory dwelling unit (ADU) sales with California state law. The action updates county policy to allow the separate sale or conveyance of ADUs under a framework authorized by Assembly Bill 1033 (AB 1033), a state measure that took effect in 2024 and permits local governments to opt in through local ordinance.

The change applies to unincorporated areas of San Diego County, where county land-use regulations govern. It does not automatically change rules inside the county’s incorporated cities, which may adopt their own ordinances and implementation standards.

What AB 1033 authorizes—and what it requires

AB 1033 created a legal mechanism for a local agency to allow a primary dwelling unit and its ADU or ADUs to be conveyed separately as condominiums, provided the jurisdiction adopts an implementing ordinance. The law also includes requirements tied to condominium creation and subdivision approvals, which can involve compliance with the Subdivision Map Act and the Davis-Stirling Common Interest Development Act.

A key operational requirement in the state framework is lender consent when a lien exists on the property: prior to recordation or modification of a subdivision map and condominium plan, lienholders must provide written consent in a form that confirms approval of recordation and acknowledgement of any terms and conditions imposed by the lender.

• Local implementation is optional; separate ADU conveyance depends on a jurisdiction adopting an ordinance.
• Condominium conversion triggers mapping, recordation and governance requirements commonly associated with common-interest developments.
• Where a lien is present, lender consent is required before recordation steps can move forward.

How the county arrived at the vote

County planning materials outline that the Board of Supervisors first directed staff on March 13, 2024, to evaluate the feasibility of implementing AB 1033 locally. The county’s Planning Commission later considered recommendations on December 5, 2025, as part of an ADU Zoning Ordinance Amendment package that included the separate sale concept. The March 4, 2026, board vote finalized the county’s ordinance alignment with the state’s opt-in framework.

Practical implications for homeowners and buyers

The ordinance is expected to create a new legal route for property owners in unincorporated communities to convert eligible ADUs into condominium interests that may be conveyed separately from the main home. However, the ability to complete an actual separate sale can depend on meeting mapping and condominium requirements, recordation steps, and financing constraints that may arise from lender consent and underwriting practices for newly created condominiumized ADUs.

The county action updates local rules to match a state-authorized pathway for separate conveyance, while leaving condominium formation and recordation requirements intact.