ADU (Accessory Dwelling Unit) permits across Arizona
Where each city draws the line on adu (accessory dwelling unit) work. Sort any column — useful if you build across several towns and need to know where the rules change.
Cities compared
12
Always need one
12
Depends on size
0
| Where the line falls | Fee | |||
|---|---|---|---|---|
| Mesa | 517,151 | Yes | Building an accessory dwelling unit (a casita, garage apa… | The code does not print a dollar amount. Building and plann… |
| Gilbert | 288,790 | Yes | Plan on a building permit (plus electrical, plumbing, and… | The code does not print a dollar amount. Permit fees are se… |
| Chandler | 281,231 | Yes | Building an accessory dwelling unit (a casita, garage apa… | The code does not print a dollar amount. Chandler sets perm… |
| Glendale | 258,143 | Yes | Building an accessory dwelling unit (garage apartment, ca… | The code prints no dollar amount. Building permit fees are … |
| Scottsdale | 246,170 | Yes | Plan on a building permit plus zoning approval to build a… | The code does not print a dollar amount. Building permit fe… |
| Tempe | 190,114 | Yes | Building an accessory dwelling unit (garage apartment, ca… | — |
| Surprise | 167,564 | Yes | Building an accessory dwelling unit (casita, garage apart… | The code does not print a dollar amount. Surprise sets perm… |
| Buckeye | 114,334 | Yes | Building an accessory dwelling unit (casita, garage apart… | Building permit plus development impact fees per City of Bu… |
| Avondale | 96,609 | Yes | Building an accessory dwelling unit (casita, garage apart… | Building permit fees are set by the Chief Building Official… |
| Bullhead City | 43,266 | Yes | A garage apartment, casita, or other accessory dwelling u… | Fees follow the City of Bullhead City Comprehensive Fee Sch… |
| Douglas | 15,819 | Yes | Building an accessory dwelling unit (garage apartment, ca… | Building permit fees per 15.08.010, valuation-based (reside… |
| Cottonwood | 12,939 | Yes | An accessory dwelling unit is a habitable structure; the … | — |
“Unconfirmed” means the city's code doesn't state the rule plainly enough to publish. Those city pages link straight to the ordinance section instead.
Why neighboring cities disagree
Every city starts from a model code and then edits it. One town raises the shed cutoff, the next lowers the fence height, a third exempts the structure where its neighbor only exempts repairs to it. None of that is visible from a national article — you have to read each ordinance, which is what these pages do.