ADU (Accessory Dwelling Unit) Permit in San Antonio (2026)
ADU (Accessory Dwelling Unit) permit requirements, fees, and process for San Antonio, TX. Find out if you need a permit and how to apply.
Yes, a ADU (Accessory Dwelling Unit) permit is required in San Antonio, TX.
A ADU (Accessory Dwelling Unit) permit is required in San Antonio, TX. The City of San Antonio Development Services Department (DSD) handles permit applications for San Antonio. Below you will find the current thresholds, fees, and process for obtaining a adu (accessory dwelling unit) permit in San Antonio.
When Is a Permit Required?
When a ADU (Accessory Dwelling Unit) Permit Is Required in San Antonio: All secondary dwelling unit construction
Permit Fees
ADU (Accessory Dwelling Unit) Permit Fees in San Antonio: $2,000–$8,000 including impact fees. Estimated timeline: 4-8 weeks.
Estimated timeline: 4-8 weeks
How to Get a ADU (Accessory Dwelling Unit) Permit in San Antonio
Verify whether your project meets the permit threshold in San Antonio: All secondary dwelling unit construction.
Prepare your permit application and plans. Contact the City of San Antonio Development Services Department (DSD) at https://www.sanantonio.gov/DSD for required documentation.
Submit your application online at https://www.sanantonio.gov/DSD/Permits/PermitPortal or in person at the City of San Antonio Development Services Department (DSD).
Pay the permit fee: $2,000–$8,000 including impact fees.
Wait for plan check approval. Estimated timeline: 4-8 weeks.
Schedule required inspections through https://www.sanantonio.gov/DSD/Inspections. All inspections must pass before project is finalized.
Important: San Antonio DSD building permit required. SAWS (San Antonio Water System) connection and impact fees apply for new utility connections. UDC Section 35-311 standards must be met.
City of San Antonio Development Services Department (DSD)
Phone: (210) 207-1111
Website: https://www.sanantonio.gov/DSD
Online Permits: https://www.sanantonio.gov/DSD/Permits/PermitPortal
Hours: Mon-Fri 7:45am-4:30pm
Frequently Asked Questions
Can I build a secondary dwelling unit (ADU) on my San Antonio property?
Yes. San Antonio allows secondary dwelling units on most residential lots under the Unified Development Code (UDC) Section 35-311. The unit can be up to 1,000 sqft for detached units. No owner-occupancy requirement in most zones. You'll need a building permit from the Development Services Department (DSD). SAWS (San Antonio Water System) connection fees apply for new utility service.
What zone is my San Antonio property in?
Use the San Antonio GIS Zoning Map at gis.sanantonio.gov/DSD/ZoningMap to look up your property's zoning designation. The city uses R-1 through R-6 for single-family and RM-4 through RM-6 for multifamily residential zones. You can also contact DSD at (210) 207-1111 for zoning verification.
Are short-term rentals (Airbnb) allowed in San Antonio?
Yes, with registration. San Antonio requires STR registration for all rentals of 30 days or fewer. The fee is $200/year. Both owner-occupied and non-owner-occupied STRs are allowed with registration. Hotel Occupancy Tax (HOT) must be collected. Your registration number must appear on all booking platform listings. Noise ordinance and occupancy limits apply.
Does San Antonio have historic district restrictions?
Yes. San Antonio has some of the strongest historic preservation rules in Texas. If your property is in a local historic district (King William, Lavaca, Government Hill, and others) or is a designated landmark, exterior alterations require a Certificate of Appropriateness from the Historic Design and Review Commission (HDRC). The process applies to all exterior changes including additions, new construction, and demolition.
What are the utility providers in San Antonio?
CPS Energy (City Public Service) provides electricity and natural gas for San Antonio. SAWS (San Antonio Water System) provides water and wastewater service. Both are city-owned utilities. CPS Energy handles interconnection for solar installations and offers net metering. New SAWS connections and impact fees apply when adding dwelling units.
Does San Antonio charge impact fees for residential development?
Yes. Unlike Dallas, San Antonio does charge impact fees for residential development. Fees depend on location and the type of utility connection required. SAWS (San Antonio Water System) charges connection fees for new water and wastewater service. Contact San Antonio DSD and SAWS for current fee schedules before planning a project.
Source: San Antonio Building Code — ADU (Accessory Dwelling Unit) Requirements. Last verified April 6, 2026. View source