ADU guides · Updated October 2026

Phoenix ADU guides: short answers first.

Each guide opens with a direct answer, then the details and the cases where it depends. Every rule and figure carries a date and an Arizona or local source.

Cost and income

How much does an ADU cost in Phoenix?Published 2026 ranges by ADU type, the costs on top of construction, and why bids differ.Read the guide How much rent can an ADU make in Phoenix?Current Phoenix rents by unit size, and what pushes an ADU's rent up or down.Read the guide

Rules

What are the ADU rules in Phoenix in 2026?HB 2720, the 2025 amendment and Phoenix's own numbers for size, height and setbacks.Read the guide Can my HOA stop me from building an ADU in Phoenix?Why city approval and HOA approval are two separate questions.Read the guide

Use and design

Can I use my ADU as a short-term rental in Phoenix?Phoenix's STR permit, the owner-on-site rule and how Scottsdale compares.Read the guide How do I keep an ADU cool in the Phoenix heat?Orientation, shade, insulation and cooling for a small building in a hot city.Read the guide

Have a specific lot in mind?

Guides cover the general rules. Send your address and we check your parcel. We work in Phoenix, Scottsdale, Tempe, Glendale and Paradise Valley.