Permit Required? Required
Typical Fee Range $1,500–$5,000 Total includes building, zoning review, and all mechanical, electrical, and plumbing trade permits.
Fee Method Valuation-based
Apply Online Apply at City of San Antonio Development Services Department →

What's Required in San Antonio

  • Required for all habitable secondary units with kitchen/bath facilities.
  • Maximum size is generally 1,100 sq ft or 50% of the main house square footage.
  • Owner must reside on the property (in either unit).
  • Must follow International Residential Code (IRC) for all habitable spaces.
  • Separate utility meters may be required depending on SAWS/CPS policies.
  • Zoning review ensures the ADU meets setback and density requirements.

How to Get a ADU Permit in San Antonio

1

Step 1: Zoning Review

Consult a DSD Planner to verify ADU allowance on your lot.

2

Step 2: Full Plan Design

Hire a professional for full IRC-compliant architectural and MEP plans.

3

Step 3: BuildSA Submission

Apply for 'Residential New Construction' for the ADU unit.

4

Step 4: Permit Payment

Pay building and impact fees (estimated $1,500+ total).

5

Step 5: Full Inspections

Schedule the same inspection sequence as a new home (Slab, Frame, Trades, Final).

Frequently Asked Questions

Yes, provided you meet size and owner-occupancy requirements.
Permit fees generally range from $1,500 to $5,000, not including construction.
Up to 1,100 sq ft or 50% of the primary dwelling's size.