Accessory Dwelling Unit (ADU) Permit in Unincorporated Cochise County, Arizona

Unincorporated Cochise County requires an accessory dwelling unit (adu) permit for: Property must have an existing single-family home; the property owner must occupy either the primary dwelling or the ADU as their primary residence; ADU must be equal to or lesser in height than the principal dwelling, and limited to 75% of the principal dwelling's gross (heated/cooled) square footage or 1,000 sq ft, whichever is less; ADUs permitted as an accessory use on any parcel where a single-family dwelling is allowed — at least one attached and one detached ADU per parcel; on lots one acre or larger, one additional detached ADU is permitted (except near airport high-noise/accident-potential zones); ADU cannot be subdivided or segregated in ownership from the principal dwelling; Recreational vehicles, railroad cars, and camper shells are NOT permitted as an ADU in any zoning district; park model trailers ARE permitted per A.R.S. §11-820.03 on parcels zoned one dwelling unit per 3+ acres, on a semi-permanent/permanent foundation; Manufactured homes/rehabilitated mobile homes permitted as an ADU only in zoning districts where they are otherwise a permitted use; Special Use Authorization required for commercial use of an ADU; a Variance is required for any deviation from ADU development standards; Complete the ADU application and submit online through the Cochise County permitting portal under 'Apply for a P&Z project' before applying for the residential building permit. If your project isn't listed, confirm with Cochise County Development Services Department — Building Safety Division at 520-432-9300 before starting work.

In Unincorporated Cochise County, the published Accessory Living Quarters (ADU) planning review/processing fee is: $100. These are the jurisdiction's own published figures — see the fee schedule table and source citations on this page.

Unincorporated Cochise County does not publish a plan-review timeline for this permit. Contact Cochise County Development Services Department — Building Safety Division at 520-432-9300 for current turnaround.

You'll need: Accessory Dwelling Unit Application (PDF); Site Plan showing ADU development-standard compliance. See the required-documents checklist on this page for details on each.

Unincorporated Cochise County requires 1 inspection(s) for an accessory dwelling unit (adu) permit, in order: Final (under subsequently issued residential building permit). Schedule each through Cochise County Development Services Department — Building Safety Division (520-432-9300).

Apply through Cochise County Development Services Department — Building Safety Division at 1415 Melody Lane, Building F, Bisbee, AZ 85603. Phone: 520-432-9300, email: developmentservices@cochise.az.gov. Office hours: Mon–Fri 8:00 AM – 5:00 PM. Official information: https://www.cochise.az.gov/202/Development-Services.

Unincorporated Cochise County, Arizona has adopted: 2015 International Building Code (IBC), with Cochise County local amendments — current as of building-safety and FAQ pages accessed 2026-07-07; 2015 International Residential Code (IRC), with Cochise County local amendments, plus Appendix Q (Tiny Houses) of the 2018 IRC adopted separately; 2015 International Existing Building Code (IEBC); 2015 International Mechanical Code (IMC); 2015 International Fire Code (IFC); 2015 International Fuel Gas Code (IFGC); 2015 International Plumbing Code (IPC); 2015 International Swimming Pool and Spa Code (ISPSC) — inserted in place of IBC Section 3109 per local amendment; NFPA 70 National Electrical Code (NEC), 2014 Edition; Sound Attenuation Ordinance, as mandated by A.R.S. §§28-8481 and 28-8482; NOTE: Cochise County is actively developing a Building Code update (CP2045 implementation) as of mid-2026, with a Builder's Roundtable held May 28, 2026 and a Building Code Advisory and Appeals Board reviewing proposed amendments; the 2015-edition code set above remains the adopted/in-force code as of this file's lastVerified date — no new edition has been adopted yet.. Local amendments apply — see the Unincorporated Cochise County overview page for the full list.

Yes, in zoning districts where a single-family dwelling is permitted, subject to owner-occupancy, height, and size limits (75% of the principal dwelling's gross square footage or 1,000 sq ft, whichever is less). Written Planning Division approval is required before you can apply for the residential building permit. Source: https://www.cochise.az.gov/237/Accessory-Dwelling-Units