Accessory Structures in Pima County, AZ (2026)
4 county-level rules, plus city-specific rules for 2 cities in Pima County, Arizona.
Verified from official government sources
ADU Rules
Unincorporated Pima County allows one attached and one detached ADU per residential lot, with strict setback and size standards to qualify.
Pima County ADU Permitting Standards
Some RestrictionsPima County Code § 18.09.020(U)
Accessory dwelling units are permitted on any residential or rural lot which allows a single-family dwelling. 2. Permitted coverage: Accessory dwelling unit square footage counts toward the accessory structure lot coverage limits for the zone in which the accessory dwelling unit is located and are permitted up to the maximum allowed by Section 18.09.020.U.5. Accessory dwelling unit(s) a...
ADU Owner Occupancy
If a Pima County property in the unincorporated area has an accessory dwelling unit, the owner must live there to legally rent it out short-term for stays of 30 days or less.
Pima County ADU Owner-Occupancy Rule
Some RestrictionsPima County Code § 18.09.020.U.10
The owner of a vacation rental or short-term rental of thirty days or less must reside on the property if the property contains an accessory dwelling unit. 11. No additional parking is required for accessory dwelling units to accommodate an accessory dwelling unit. 12. All Pima County Code regulations still apply, including, but not limited to, Protected Peaks ( 18.61), Hillside...
ADU Rental Restrictions
In unincorporated Pima County, the zoning code lets an accessory dwelling unit be rented short-term or long-term, and its square footage still counts toward the lot's coverage limits.
Pima County ADU Short-Term Rental Use
Few RestrictionsPima County Code § 18.09.020.U.9
Accessory dwelling unit(s) may be used as a short- or long-term rental. 10. The owner of a vacation rental or short-term rental of thirty days or less must reside on the property if the property contains an accessory dwelling unit. 11. No additional parking is required for accessory dwelling units to accommodate an accessory dwelling unit. 12. All Pima County Code regula...
Shed & Carport Rules
In CR-1 single-residence zoning covering unincorporated Pima County, sheds and accessory buildings max out at 1,500 sq ft (or 70% of the main house) and 24 feet tall.
Pima County Shed & Accessory Building Rules
Some RestrictionsPima County Code § 18.21.040 (CR-1 Single Residence Zone)
A. Permitted coverage: Fifteen hundred square feet, or seventy percent of the area of the largest main building on the lot, whichever is greater. B. Maximum height: Twenty-four feet. C. Minimum distance standards: 1. To front lot line: Sixty feet; 2. To side and rear lot lines: a. Four feet if building is not used for poultry or animals, b. Fifty feet if building is used for poultry or animals,
Accessory Structures by City in Pima County
2 cities in Pima County have their own accessory structures rules. Each link goes to that city's dedicated page with code citations.
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