Arizona ADU Laws

Complete 2026 guide to accessory dwelling unit regulations

✓Strong Statewide Law

📋Quick Facts

Max Size
1,000 sq ft
Size Limit
75% of primary
Owner Occupancy
May be required
Parking
Set locally
Approval Process
✓ By-right
Effective Date
5/21/2024

📜Recent Legislation

HB 2720 (2024) - Statewide ADU mandate for cities 75k+ population

⚠️Key Requirements & Restrictions

  • •Applies only to municipalities with 75,000+ residents
  • •HOA rules can still restrict ADUs
  • •Local design/location regulations may apply

📖Detailed Analysis

HB 2720 signed May 21, 2024 by Gov. Hobbs. Mandates cities 75k+ allow at least one attached AND one detached ADU per lot in single-family zones. Phoenix allows up to 2 ADUs (1 attached + 1 detached), 3rd allowed on 1+ acre lots if one is affordable housing. Phoenix max size: 75% of main house or 1,000 sqft (lots up to 10k sqft). Tucson max: 75% or 1,000 sqft, minimum 650 sqft guaranteed. HOAs can still restrict - statewide law does not override private covenants.

🔗Official Resources

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⚠️ Disclaimer

The information provided on this website is for general informational purposes only and does not constitute legal, financial, or professional advice. ADU laws, regulations, and requirements vary by jurisdiction and change frequently. While we strive to keep this information accurate and up-to-date, we make no representations or warranties of any kind about the completeness, accuracy, reliability, or suitability of this information. Always consult with qualified local professionals, including attorneys, architects, and your local planning department, before making any decisions regarding ADU construction or investment. Use of this information is at your own risk.

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Last updated: February 2026