Accessory dwelling unit near me

Looking for accessory dwelling unit near me in Ontario, CA? Call AccessoryDwellingUnit Solutions for a contact a provider — no obligation. Licensed adu builders serve Ontario and the surrounding area, and you'll get straight answers on timing and what affects the price.

Last updated: September 24, 2026

What affects the price

Building an ADU involves several moving parts that shape your total budget. The biggest factor is whether you choose a prefabricated unit or a custom build on-site. Site preparation is also significant; if your land requires extensive grading, utility trenching, or foundation work, costs will climb. Your choice of finishes—like kitchen cabinetry, flooring, and siding materials—also shifts the bottom line. We help you navigate these variables to find a setup that fits your property. Exact pricing confirmed free on the call.

About this service

This search helps you find established professionals who understand the specific land-use regulations in your neighborhood. You need this when you are in the research phase and want to see examples of completed work in your immediate area. Finding help nearby allows you to discuss specific zoning challenges related to your lot size and setbacks with experts who have already navigated the requirements of your local municipal office.

Frequently asked in Ontario

What are the disadvantages of ADUs in Ontario?

Disadvantages can include the initial construction costs and the potential impact on your yard space. Ontario's specific zoning regulations regarding size and placement are also important factors. However, many homeowners find the increased property value and rental income opportunities outweigh these concerns.

How much does an ADU cost in California?

The cost of an ADU in California varies greatly depending on size, materials, and site-specific needs in Ontario. Factors like foundation requirements and utility connections significantly impact the price. A personalized quote is the best way to get an accurate cost estimate.

What are the rules for ADUs in Ontario?

Ontario has specific local ordinances that govern accessory dwelling units, including regulations on size, height, and setbacks. You'll need to ensure your proposed ADU complies with these rules. We can help you find professionals well-versed in these local requirements.

Is an ADU allowed in California?

Yes, accessory dwelling units are widely permitted in California due to state laws encouraging their development. However, each city, including Ontario, has its own specific ordinances that must be followed. Verifying these local rules is crucial.

What are the rules for ADUs in California?

California has state laws that streamline ADU development, often setting minimum standards that cities must adhere to. Local jurisdictions still have specific requirements regarding size, height, setbacks, and parking. It's essential to consult the specific city's municipal code.

California has offered various grant programs to help offset the costs of ADU construction, particularly for affordable housing initiatives. The availability and specific terms of these grants can change. Researching current state and local housing programs is recommended.

Also serving nearby: Chino · Rancho Cucamonga · Jurupa Valley · Pomona · Fontana

All cities in California →

More on this: HUD ADU resources — ADU policy and financing research.

Service area details

182,457residents

3,650per sq mile

4ZIP codes served

Serving all of Ontario — population 182,457; about 3,650 residents per square mile across 50.0 sq mi. ZIP codes covered include 91758, 91761, 91762, 91764.

Neighborhoods served in Ontario: Downtown Ontario, Central Park, De Anza, Sunkist, Montclair — and every surrounding area.