ADU Rules in Tucson, AZ (2026)

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 Tucson Planning and Development Services Department (PDSD) 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 50% of primary dwelling floor area or 1,200 sqft, whichever is less (max height: 20 feet). Attached ADU: 50% of primary dwelling floor area. Arizona does not have a JADU concept equivalent to California's Gov Code 65852.22. 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.

Permit Fees

ADU Permit Fees in Tucson: Plan check fee: $200–$1,200. Building permit fee: Based on construction value — typically $700–$3,000. Impact fees: Tucson transportation and water impact fees may apply depending on ADU type and utility service. School fees: None or N/A. Total estimated permit cost: $1,500–$8,000 total fees including development fees. Tucson Water connection fees for new water/sewer service (typically $1,500–$5,000 depending on meter size). Tucson Transportation Impact Fee may apply for new dwelling units. Fee schedule: https://www.tucsonaz.gov/pdsd/fees

Permit Timeline

Tucson ADU Permit Timeline: Tucson PDSD building permit: typically 3-6 weeks for residential ADU. Electronic plan review available via Tucson's Online Services portal. Construction typically 3-9 months. Tucson's permitting process is generally more streamlined than Phoenix due to smaller permit volume. Apply through the Tucson Planning and Development Services Department (PDSD) online permit portal. Phone: (520) 791-5550.

Setback Requirements

ADU Setback Requirements in Tucson: Front setback: follows zone standard. Side setback: 5 feet. Rear setback: 5 feet. Per Arizona HB 2297, municipalities cannot require rear or side setbacks greater than 5 feet for ADUs. Tucson's UDC was updated to reflect this maximum. Front setback follows primary dwelling line per applicable zone standard. R-1 zones typically require 25 ft front setback for primary dwellings.

Parking Requirements

Parking Requirements: No additional off-street parking required for ADUs per Arizona HB 2297. Tucson cannot require additional parking for ADUs as a condition of approval under state law.

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: 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. Arizona HB 2297 (2024) requires at least 1 ADU to be allowed on lots with single-family dwellings in municipalities with populations over 5,000. Tucson's UDC may allow additional ADUs in some zones — contact PDSD for guidance.

State Law & Preemption

Historic District Considerations

Frequently Asked Questions