ADU Rules in Tucson, AZ (2026)
ADU rules, permit requirements, size limits, and fees for Tucson, AZ. Source-cited from official municipal code.
Yes, ADUs are allowed in Tucson, AZ.
Tucson, AZ permits accessory dwelling units (ADUs) on residential properties. ADUs — also called granny flats, in-law units, backyard cottages, or secondary suites — are secondary housing units on a single-family or multifamily lot. State and local law actively preempts local restrictions, making ADU approval a streamlined ministerial process. In Tucson, the local building department handles ADU permit applications. Below you will find the current size limits, setbacks, fees, and timeline for building an ADU in Tucson.
ADU Size Limits
ADU Size Limits in Tucson: Detached ADU: up to seventy-five percent of the gross floor area of the single-family dwelling on the same lot or parcel or one thousand square feet, whichever is less (max height: varies — see official source). Attached ADU: size varies by zoning — see official source. Arizona does not have a JADU concept equivalent to California's §66313(d) (JADU; formerly §65852.22, recodified by SB 477, 2024). Tucson UDC limits ADU to 50% of primary dwelling or 1,200 sqft. University of Arizona proximity makes smaller (400-700 sqft) studio ADUs highly rentable to graduate students.
| Type | Max Size | Max Height |
|---|---|---|
| Detached ADU | seventy-five percent of the gross floor area of the single-family dwelling on the same lot or parcel or one thousand square feet, whichever is less · Verified June 4, 2026 · Source | See official source |
| Attached ADU | See official source | See official source |
Permit Fees
ADU Permit Fees in Tucson: Plan check fee: Varies. Building permit fee: Varies. Impact fees: None. School fees: None or N/A. Total estimated permit cost: Varies.
| Fee Type | Amount |
|---|---|
| Plan Check | None |
| Building Permit | None |
| Impact Fees | None |
| School Fees | None |
| Total Estimate | None |
Permit Timeline
Tucson ADU Permit Timeline: Permit timeline has not been confirmed — contact the department for current processing times. Apply through the local building department online permit portal. Phone: (520) 791-5550.
Setback Requirements
ADU Setback Requirements in Tucson: Front setback: follows zone standard. Side setback: no minimum. Rear setback: no minimum.
Parking Requirements
Parking Requirements: Municipality may not require that a lot or parcel have additional parking to accommodate an accessory dwelling unit or require payment of fees instead of additional parking
Restrictions & Requirements
- ADU must be on same lot as primary single-family dwelling
- Maximum size: 50% of primary dwelling or 1,200 sqft
- One ADU per single-family residential lot per HB 2297
- Corner lots may have additional street-facing setback requirements
- Impervious surface and lot coverage limits apply per UDC zone
- Saguaro cactus protection: any ADU construction requiring excavation near a Saguaro requires AZ Game & Fish permit for relocation
How Many ADUs Are Allowed?
Number of ADUs Allowed in Tucson: Single-family lots: not confirmed — see official source. Multifamily properties: not confirmed — see official source.
- Single-Family Lots
- 1 ADU per single-family lot per Arizona HB 2297
- Multifamily Properties
- ADUs allowed in some multifamily zones per Tucson UDC — consult PDSD for specific zone standards
Statewide Preemption
ADU Preemption
Arizona state law preempts local ADU rules — local governments cannot impose stricter standards.
View Arizona preemption detailsState Law & Preemption
State Preemption: AZ state law preempts local ADU restrictions. Tucson must approve compliant ADU applications by right.
Frequently Asked Questions
Can I build an ADU in Tucson?
Yes. Tucson, AZ allows accessory dwelling units. On a single-family lot you can build 1 ADU per single-family lot per Arizona HB 2297.
How big can an ADU be in Tucson?
The maximum size for a detached ADU in Tucson is seventy-five percent of the gross floor area of the single-family dwelling on the same lot or parcel or one thousand square feet, whichever is less square feet.
How long does it take to get an ADU permit in Tucson?
The typical ADU permit timeline in Tucson is Contact Tucson PDSD for ADU permit processing timeline — see tucsonaz.gov/pdsd.
Do I need extra parking for an ADU in Tucson?
Tucson parking rules for ADUs: Municipality may not require that a lot or parcel have additional parking to accommodate an accessory dwelling unit or require payment of fees instead of additional parking
Do I have to live on-site to have an ADU in Tucson?
Owner-occupancy requirement in Tucson: No familial, marital, employment or other preexisting relationship required between owner or occupant of single-family dwelling and occupant of accessory dwelling unit
Source: Tucson Unified Development Code Section 6.7.4 — Accessory Dwelling Units; Arizona HB 2297 (Laws 2024, Chapter 204). Last verified April 6, 2026. View source