Pomona, CA Accessory Structures: ADU Impact Fees (2026)

Sec. a of Pomona's Zoning and Development Code sets impact fees for accessory dwelling units. No impact fee is required for an ADU that is less than or equal to 749 square feet in area. Any impact fee required for an ADU of 750 square feet or larger must be charged proportionately in relation to the square footage of the primary dwelling unit, calculated as the floor area of the primary dwelling divided by the floor area of the ADU, times the typical fee amount charged for a new dwelling.

The code specifies that 'impact fee' in this section does not include any connection fee or capacity charge for water or sewer service, which are addressed separately under Sec. b. Utility Fees and Connections. If an ADU is built alongside a new single-family home, a separate utility connection and the normal connection fee and capacity charge for a new dwelling are required. Converted ADUs on a single-family lot created as an Interior ADU under Sec. 1 are not required to have a new or separate utility connection, and no connection fee or capacity charge applies to them.

All other ADUs not covered by that exception require a new, separate utility connection, subject to a connection fee or capacity charge proportionate to the burden the ADU creates, measured by floor area or by drainage-fixture units under the Uniform Plumbing Code, and the City-charged portion of that fee cannot exceed the reasonable cost of providing the service.