Imperial County, CA Accessory Structures: ADU Impact Fees (2026)
Key Facts
- Exempt threshold
- Under 750 sq ft
- Fee cap
- Proportional to primary home
- Authority
- Gov. Code § 65852.2(f)(3)
- Connection fees
- Also proportional, not flat
Summary
Imperial County exempts ADUs under 750 square feet from impact fees entirely, and caps fees on larger units proportional to the primary home's square footage.
Impact fee exemptions and limitations are based on the size of the ADU. ADUs up to seven hundred fifty (750) square feet are exempt from impact fees, and ADUs that are seven hundred fifty (750) square feet or larger may be charged impact fees but only such fees that are proportional in size (by square foot) to those for the primary dwelling unit. (Gov. Code, § 65852.2, subd. (f)(3))U.Property owners have the option of installing a new electrical meter if the local electrical utility company (Imperial Irrigation District) does not object to the installation of an additional service on the property, subject to the following conditions:a)A second electrical service panel (meter) for ADU only must be installed adjacent to the existing electrical service panel for the primary residential dwelling. In the event of an emergency, the County Fire Department must be able to shut off all services in one (1) location.b)The new service only applies to ADUs and not attached garages. A subpanel would be required for a new garage. (Ord. No. 1565, §§ 1, 2, 12-15-20; Ord. No. 1587, §§ 1, 2, 12-5-23; Ord. No. 1593, §§ 7, 8, 6-18-24)
Official source re-checked September 7, 2026: no newer edition of the code had been published (publisher’s edition: Code of Ordinances: Supplement 62 - 9-25).
Full Breakdown
Under Imperial County Code, an accessory dwelling unit smaller than 750 square feet pays no impact fees at all. Once an ADU reaches 750 square feet or more, the county may charge impact fees, but only in proportion, by square footage, to what the primary dwelling would pay. Water and sewer connection or capacity charges follow the same proportionality rule when the ADU counts as a new residential use.
Violations & Fines
There is no owner violation here: the restriction runs against the county: it cannot assess a flat impact fee on ADUs under 750 sq ft, or a disproportionate fee on larger units.
Frequently Asked Questions
Does Imperial County charge impact fees on ADUs?
Are ADU water/sewer connection fees different?
Sources & Official References
Other rules in Imperial County
California rules heatmap·Compare Imperial County to another location·View the California accessory structures overview
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