Santa Clarita ADU connects homeowners in eight Santa Clarita Valley communities with a local ADU contractor. Four of them are inside the City of Santa Clarita. The other four are unincorporated Los Angeles County. That split decides where your ADU permit goes, so it’s the first thing to know about your address.
Which communities do you serve?
| Community | Where ADU permits go | What shapes an ADU there |
|---|---|---|
| Valencia | City of Santa Clarita | More than a dozen master-planned neighborhoods, each with its own HOA, so HOA design review is common |
| Newhall | City of Santa Clarita | Smaller, older lots around Old Town Newhall, where garage conversions are often practical |
| Saugus | City of Santa Clarita | Everything from 1950s Bouquet Canyon tracts to new Skyline Ranch homes, where HOA review is typical |
| Canyon Country | City of Santa Clarita | The widest range of lot sizes, from Sand Canyon horse property to denser tracts, with some parcels in fire hazard zones |
| Stevenson Ranch | LA County | A built-out master-planned community with 46 neighborhoods, where HOA review is common |
| Castaic | LA County | Ranges from no-HOA Live Oak to tracts with HOAs and Mello-Roos, with some parcels near wildland areas |
| Acton | LA County | Mostly light agricultural lots, where septic systems and fire hazard zones are common |
| Agua Dulce | LA County | Rural ranch and airpark properties, where septic systems and fire hazard zones are common |
For how ADU rules work across the whole city, see the City of Santa Clarita overview.
Why does city vs. LA County matter for an ADU?
In Valencia, Newhall, Saugus, and Canyon Country, ADU applications go to the City of Santa Clarita’s Planning Division under the city’s ADU ordinance. In Stevenson Ranch, Castaic, Acton, and Agua Dulce, they go to the LA County Department of Regional Planning under the county’s separate ordinance.
Some things are the same everywhere, because state law sets them:
- Ministerial review. A compliant ADU is approved without a public hearing.
- A 60-day decision. The agency must decide within 60 days of a complete application.
- No minimum lot size. Cities and counties can’t require one for an ADU.
- No short-term rentals for JADUs. Every Junior ADU must be rented for more than 30 days.
Other things differ. The City of Santa Clarita doesn’t allow any ADU to be rented for less than 30 days. In the county areas, septic-served properties usually get an Environmental Health review, and rural parcels in Very High Fire Hazard Severity Zones face added access and fuel modification requirements.
How do I know if my address is in the city or the county?
Don’t go by your mailing address. Many homes outside city limits still use a Santa Clarita-area address. The City of Santa Clarita’s Planning Division can confirm whether your parcel is inside city limits, and your contractor should confirm it before anything is filed.
Don’t see your community?
Call (661) 486-8393 or send us your details to check whether we can connect you with a contractor in your area.
How do I get connected with a local ADU contractor?
- Call or send your details. Call (661) 486-8393. If no one answers, leave a voicemail with your name, phone number, address, and the type of ADU you want.
- We pass your details to a local ADU contractor. They build ADUs in the Santa Clarita Valley.
- The contractor contacts you. They follow up directly to talk through your project.
- You decide. There’s no obligation to hire. See how to choose an ADU contractor first.
Santa Clarita Valley FAQs
Is Stevenson Ranch part of the City of Santa Clarita?
No. Stevenson Ranch is unincorporated Los Angeles County, just west of the city. LA County approved it as a master-planned community in 1987. ADU permits there go through the LA County Department of Regional Planning, not the city.
Is Canyon Country its own city?
No. Canyon Country is one of the four communities, with Valencia, Newhall, and Saugus, that combined in 1987 to form the City of Santa Clarita. It’s in Los Angeles County, like the rest of the city, and ADU permits go through the City of Santa Clarita.
Is Castaic a city?
No. Castaic is an unincorporated community in Los Angeles County along the I-5 corridor. It has no city government, so ADU permits go through LA County.
Is Agua Dulce part of Santa Clarita?
No. Agua Dulce is a small, rural town of about 4,000 people in unincorporated Los Angeles County. ADU permits there go through the county, and many properties are on septic systems or in fire hazard zones.
Is Newhall its own city?
No. Newhall is the historic core of the City of Santa Clarita, dating back to 1876. It became part of the city at incorporation in 1987, so ADU permits there go through the City of Santa Clarita.