Short Answer
Yes, building permitAustin allows additional dwelling units on lots zoned SF-1, SF-2 or SF-3 of at least 5,750 square feet. Since HOME Phase 1 took effect on February 5, 2024, those lots can hold up to 3 units, with no primary or secondary unit distinction and no zoning separation minimum. Each unit needs a building permit through Residential Plan Review.
Source: City of Austin: Additional Dwelling Units (linked under Sources below)
Austin ADU Permits at a Glance
- ADU permits, last 12 months
- 71
- Median application to issue
- 224 days
- Slowest quarter took at least
- 720 days
- New detached ADUs
- 39
Of the 7 cities we track for ADUs, Austin ranks slowest by median wait.
Who Can Apply and Do the Work
Apply with the New Construction and Addition Building Permit application through Residential Plan Review. Plan review fees are invoiced and paid through the AB+C portal. Each unit needs its own unique address.
What You Need Before the Permit Is Issued
- Confirm the lot is zoned SF-1, SF-2 or SF-3 and is at least 5,750 square feet.
- Check deed restrictions yourself; the City does not enforce them.
- Fire separation under IRC R302.1(1) still applies even though the zoning separation minimum is gone.
- Request an address for each unit.
What Else to Know in Austin
HOME stands for Home Options for Families and Missing Middle Housing. Phase 1 replaced the old two-unit and ADU rules on single-family lots; read the City's HOME amendments page before designing.
Austin ADU Permit Costs
Austin does not publish a flat ADU permit fee; plan check and permit fees are calculated from the project valuation when you apply, so we don't quote one.
What Austin's ADU Permit Data Shows
| Type of ADU | Permits | Share |
|---|---|---|
| Conversion of a garage, basement or other existing space | 5 | 7% |
| New detached ADU | 39 | 55% |
| Attached ADU | 12 | 17% |
| Junior ADU | 0 | 0% |
| Not specified in the description | 15 | 21% |
ADU Permits Issued per Month
Types are classified from each permit's description. Building permits whose description mentions an ADU or additional or accessory dwelling unit. Data from Austin Issued Construction Permits, October 30, 2025 to October 30, 2026.
Where ADUs Are Being Permitted
| ZIP code | Permits (12 mo) |
|---|---|
| 78704 | 16 |
| 78744 | 11 |
| 78757 | 6 |
| 78702 | 5 |
| 78703 | 5 |
| 78752 | 5 |
Recent ADU Permits
| Issued | Work as described by the city |
|---|---|
| 2026-10-22 | *Green Building* New 2-story 4 bedroom 3.5 bathroom two-family (duplex) residence with attached garage covered |
| 2026-10-15 | Building 2 2 Story SFR rear of main house with alley access - ADU / Garage |
| 2026-10-12 | *Green Building* New 2-story 4 bedroom 3.5 bathroom two-family (duplex) residence with attached garage covered |
| 2026-10-09 | Addition and remodel to existing 2-story residence part of two-unit use per the Home ordinance (originally bui |
| 2026-08-13 | *Green Building* New 2-story 4 bedroom 3.5 bathroom two-family (duplex) residence with attached garage covered |
| 2026-08-12 | *Green Building* New 2-story 4 bedroom 3.5 bathroom two-family (duplex) residence with attached garage covered |
How to Get an ADU Permit in Austin
- Confirm what your lot allows. Zoning, existing unit count, hillside, fire and historic status decide which ADU types and how many you can add.
- Choose the program and plans. Decide between the State program and the Local program; they cannot be combined.
- Complete the prerequisites listed above before you file.
- File the building permit through PermitSF, over the counter or for in-house review.
- Build, pass inspections and get final sign-off before anyone moves in.
Frequently Asked Questions
Do I need a permit to build an ADU in Austin?
Austin allows additional dwelling units on lots zoned SF-1, SF-2 or SF-3 of at least 5,750 square feet. Since HOME Phase 1 took effect on February 5, 2024, those lots can hold up to 3 units, with no primary or secondary unit distinction and no zoning separation minimum. Each unit needs a building permit through Residential Plan Review.
How long does an ADU permit take in Austin?
For the 71 ADU permits issued between October 30, 2025 and October 30, 2026 with both dates published, the median time from application to issue was 224 days, and a quarter took 720 days or longer, according to the city's open data.
How many ADU permits does Austin issue?
71 in the 12 months to October 30, 2026. About 7% converted existing space such as a garage, 55% were new detached units, 17% were attached and 0% were junior ADUs, based on the permit descriptions.
How many units can I build on an Austin single-family lot?
Up to 3 units on lots zoned SF-1, SF-2 or SF-3 of at least 5,750 square feet, under HOME Phase 1, effective February 5, 2024.
Related Permit Guides
- Austin Building Permits
- ADU Permit Requirements: What Homeowners Need to Know
- Los Angeles ADU Permit Requirements
- San Francisco ADU Permit Requirements
- San Diego ADU Permit Requirements
- Chicago ADU Permit Requirements
- Seattle ADU Permit Requirements
- New York ADU Permit Requirements
Sources
Official sources checked on . Rules change; confirm with the department before you start work.
- City of Austin: Additional Dwelling Units (austintexas.gov)
- City of Austin: HOME Amendments (austintexas.gov)
- Austin Issued Construction Permits (data.austintexas.gov)