Yorba Linda, CA Accessory Structures: ADU Impact Fees (2026)

Yorba Linda Municipal Code § 18.20.890 sets the City's ADU fee structure. Subsection A exempts any ADU smaller than 750 square feet from impact fees entirely, and for units at or above that threshold, fees are charged proportionately based on the ADU's square footage relative to the primary dwelling unit's square footage rather than as a flat per-unit charge. Subsection B goes further and waives planning processing and building plan check fees outright in two situations: first, when the applicant voluntarily records a perpetual restrictive covenant committing the owner to live in one of the dwelling units on the property as long as the ADU condition remains, recorded with the Community Development Director before the final building permit issues; and second, when an existing garage or carport is converted to an ADU or JADU and the applicant voluntarily replaces it with at least two on-site covered parking spaces for the primary residence, conforming to Section 18.22.030's parking standards.

Together these provisions mean a small owner-occupied ADU built into an existing garage can potentially avoid impact fees, planning processing fees and plan check fees altogether, while a larger, market-rate rental ADU still owes a proportional impact fee tied to its share of the lot's total square footage.