San Diego County approves ordinance allowing ADUs to be sold separately

San Diego County officials have approved a new ordinance that will allow accessory dwelling units (ADUs) to be sold separately from the primary home on a property, creating a potential new pathway to homeownership in the region.

The San Diego County Board of Supervisors unanimously approved the ordinance amendment on March 4, 2026, aligning county policy with a relatively new California state law that authorizes local governments to permit the separate sale of ADUs as condominium units (Assembly Bill 1033), according to reporting by CBS 8 San Diego. The ordinance will take effect 30 days after approval.

Supporters say the change could expand homeownership opportunities and encourage more small-scale housing development in unincorporated areas of the county.

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What the New Ordinance Allows

The updated policy allows qualifying ADUs in unincorporated areas of San Diego County to be sold separately from the main residence through a condominium structure, according to county planning documents and local reporting.

Under this framework, a property containing a primary home and an ADU could be subdivided into two condominium units, each with its own deed and ownership structure.

The county’s Land Use and Environment Group also indicated that staff will return within 120 days with additional policy options focused on expanding homeownership opportunities. These options may include giving existing tenants living in ADUs the first opportunity to purchase the unit if it is placed on the market, according to coverage from CBS 8 San Diego and regional news service reports.

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Timeline Leading to the Vote

The ordinance approval followed more than a year of policy development and public input.

County planning staff were first directed to evaluate the possibility of allowing separate ADU sales in March 2024. Later that year, in October 2024, supervisors instructed staff to move forward with developing a local implementation program under AB 1033, according to materials from the San Diego County Planning & Development Services.

The county’s Planning Commission reviewed the proposal and recommended approval in December 2025 after several rounds of public outreach and stakeholder discussions. The final ordinance was then approved by the Board of Supervisors in early March 2026.

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City vs. County Implementation

While the City of San Diego has already adopted policies allowing accessory dwelling units to be sold separately under California’s AB 1033, the newly approved ordinance applies specifically to unincorporated areas of San Diego County. According to county officials, the policy aligns local regulations with state law while establishing guidelines for how ADUs can be subdivided and sold as condominium units. Because the City of San Diego operates under its own municipal code, it adopted its own AB 1033 ordinance earlier, which took effect in August 2025.

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Why the Policy Matters

Housing experts say policies like this are designed to expand the number of smaller, more attainable homes available for purchase, particularly in high-cost housing markets like San Diego.

Accessory dwelling units have become a significant part of California’s housing strategy over the past decade. State lawmakers have passed numerous reforms aimed at making ADUs easier to build as a way to increase housing supply without requiring large new developments.

Allowing ADUs to be sold separately could further expand their role in the housing market by converting what has traditionally been rental housing into entry-level homeownership opportunities.

Housing advocates note that smaller homes—such as ADUs—may offer lower purchase prices than traditional single-family houses, which could help first-time buyers enter the housing market in expensive regions.

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Quick Tip: If you’re considering building an ADU with the goal of selling it separately in the future, check whether your property is located in the City of San Diego or unincorporated San Diego County, as the rules and approval processes may differ depending on the jurisdiction.

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Xavier Rodriguez is the CEO of ADU Geeks, San Diego’s leading ADU consulting and project management firm. In 2024, the company was ranked No. 1 on the San Diego Business Journal’s Fastest Growing Private Companies list in the Small Business category, achieving 594.3% revenue growth.