ADU Rules: Mesa vs Tempe
How do adu rules rules compare between Mesa, AZ and Tempe, AZ?
Mesa has fewer restrictions than Tempe.
Mesa, AZ
Maricopa County
Mesa allows ADUs by right in all single-residence districts under MZO Section 11-31-3 (updated by Ordinances 5883 and 5950). No minimum lot size. Maximum 1,000 sq ft or 75% of primary residence. Garage conversion parking replacement eliminated.
View full Mesa rules →Tempe, AZ
Maricopa County
Tempe permits Accessory Dwelling Units (ADUs) in residential zones following a 2022 ordinance update. ADUs can be detached, attached, or converted from existing structures. They must meet size, setback, and design standards but do not require additional parking.
View full Tempe rules →Key Facts Comparison
| Fact | Mesa | Tempe |
|---|---|---|
| Max Size | 1,000 sq ft or 75% of primary | 75% of primary home or 1,000 sq ft |
| Lot Minimum | None required | - |
| Garage Convert | No replacement parking needed | - |
| State Law | HB 2720 (2025) | - |
| Setbacks | - | 5 feet from side and rear lines |
| Parking | - | No additional parking required |
| STR Use | - | Not permitted for rentals under 30 days |
| Design | - | Must match primary dwelling style |
Highlighted rows indicate differences between cities.
Mesa FAQ
Can I build an ADU on my property in Mesa?
Mesa allows ADUs by right in all single-residence districts under MZO Section 11-31-3 (updated by Ordinances 5883 and 5950). No minimum lot size. Maximum 1,000 sq ft or 75% of primary residence. Garage conversion parking replacement eliminated.
What are the size limits for an accessory dwelling unit in Mesa?
Max Size: 1,000 sq ft or 75% of primary. Lot Minimum: None required. Garage Convert: No replacement parking needed. State Law: HB 2720 (2025).
Tempe FAQ
Can I build an ADU in Tempe?
Yes. Tempe allows one ADU per single-family lot, up to 1,000 square feet or 75% of the primary dwelling. A building permit is required.
Can I rent out my ADU on Airbnb?
No. Tempe's ADU ordinance prohibits using ADUs as short-term rentals (under 30 days). Long-term rentals are permitted.
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