Can I Build ADU in Phoenix, AZ? (2026)
Find out if you can build a adu in Phoenix, AZ. Rules, permit requirements, costs, and next steps.
Yes, ADUs are allowed in Phoenix, AZ. California state law ensures by-right approval.
An Accessory Dwelling Unit (ADU) is a secondary housing unit on a residential lot — also called a granny flat, in-law suite, or backyard cottage. In Phoenix, AZ, ADUs are permitted by right under state law, making them one of the most accessible ways to add housing on your property. ADUs can be detached, attached to the main home, or created by converting an existing garage or accessory structure.
ADU Rules in Phoenix
ADU Rules in Phoenix: Detached ADU max size: 50% of primary dwelling floor area or 1,200 sqft, whichever is less. Attached ADU max size: 50% of primary dwelling floor area. Setbacks: 5 ft side, 5 ft rear. Owner-occupancy: No owner-occupancy requirement under Arizona HB 2297. Phoenix removed its previous owner-occupancy requirement from its local ADU ordinance in 2024 to comply with state law.. State preemption applies: AZ law requires Phoenix to approve compliant ADUs by right.
Costs & Fees
ADU permits in Phoenix: Total estimated permit cost: $2,000–$10,000 total fees including development fees. Contact the Phoenix Planning and Development Department (PDD) for current fee schedule.
Timeline
Phoenix PDD building permit: typically 3-6 weeks for residential additions. Electronic plan review available via Phoenix ePermits portal. Construction typically 3-9 months.
Next Steps
Next steps for building an ADU in Phoenix: 1. Review full ADU rules including size limits, setbacks, and parking. 2. Apply for an ADU permit through the Phoenix Planning and Development Department (PDD) at https://www.phoenix.gov/pdd/permits. 3. Hire a licensed contractor familiar with AZ ADU requirements.
Phoenix Planning and Development Department (PDD)
Phone: (602) 262-7811
Website: https://www.phoenix.gov/pdd
Online Permits: https://www.phoenix.gov/pdd/permits
Frequently Asked Questions
Can I build an ADU on my Phoenix property?
Yes. Arizona HB 2297 (effective September 2024) requires Phoenix to allow ADUs on single-family lots and removed the previous owner-occupancy requirement. Phoenix updated its local ordinance to comply. ADUs can be up to 50% of your primary dwelling floor area or 1,200 sqft (whichever is less). No additional parking is required. Side and rear setbacks cannot exceed 5 feet per state law.
What are the short-term rental rules in Phoenix?
Phoenix requires STR registration ($250/year). Arizona SB 1350 (2016) originally preempted cities from banning STRs outright, but SB 1168 (2022) gave cities back some regulatory authority including the ability to require registration, impose safety requirements, and penalize nuisance properties. Maximum occupancy is 2 guests per bedroom plus 2 additional guests. A local contact person must be designated.
Does Phoenix have a solar mandate?
No, Phoenix does not have a solar mandate for new construction. However, Arizona's strong HOA solar protection law (ARS 33-1816) means your HOA cannot prohibit solar installations. Phoenix receives approximately 299 sunny days per year, making it one of the best solar markets in the US. Building permits are required for all solar installations.
What zoning district is my Phoenix property in?
You can look up your Phoenix zoning at the Phoenix Planning and Development Department website using the interactive zoning map at phoenix.gov/pdd/zoning. Most established single-family neighborhoods are zoned R1-6, R1-8, or R1-10. RE-24 and RE-43 are large-lot estate zones. R-2 through R-5 are progressively denser multifamily zones.
Are Saguaro cacti protected in Phoenix?
Yes. Saguaro cacti are protected under Arizona law. You cannot remove, destroy, or relocate a Saguaro cactus without first obtaining a permit from the Arizona Game and Fish Department. Violating this law can result in significant fines. If a Saguaro must be removed for construction, it must be relocated by a licensed cactus moving company with a valid permit.
Source: Phoenix Planning and Development Department (PDD) — Building Regulations. Last verified April 5, 2026. View source