Arlington, TX Accessory Structures: ADU Permits (2026)

Arlington regulates accessory dwelling units (ADUs) — referred to as accessory living quarters or guest quarters — under the Arlington Unified Development Code (UDC) Article 4 (Use Regulations) and Article 5 (Development Standards). In most R-1, R-2, R-3, and RS series residential districts, an ADU with full kitchen facilities is not permitted by right and requires a Specific Use Permit (SUP) under UDC § 4.4. The SUP application is filed with the Community Development and Planning Department, reviewed by Planning and Zoning Commission, and approved by Arlington City Council after a public hearing with notification to property owners within 200 ft. Approval criteria include neighborhood compatibility, parking adequacy, lot size sufficiency (typically 8,000 sq ft minimum for an ADU), and infrastructure capacity. Once the SUP is granted (typically 3–6 months), the applicant submits construction plans through the OneStart permit portal for building permit review under the 2018 International Residential Code as locally amended. Detached ADUs are subject to UDC accessory structure standards: typically 600 sq ft maximum, 15 ft maximum height, 5 ft side and rear setbacks, single-story. Texas state law has not preempted Arlington's discretionary SUP process. Bonus districts (Downtown, Entertainment District near Globe Life Field/AT&T Stadium) have different mixed-use ADU provisions.