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Emissions Testing in Ontario, California

Find 32 licensed smog check stations in Ontario. Browse test-only centers, STAR-certified locations, and shops offering registration renewal inspections. Requirements in California vary by vehicle type and model year.

32 stations
Ontario, CA
View California requirements
RM

Ramirez Mobile Clean Truck Check & Opacity Testing

5.0 · 10 reviews
Smog inspection station · 520 S Cypress Ave, Ontario, CA 91762

Ramirez Mobile Clean Truck Check & Opacity Testing offers smog check and vehicle inspection in Ontario, California. View...

smog check Vehicle Inspection OBD-II Diagnostics Check Engine Light Diagnosis
MT

Mendoza Test Only

5.0 · 5 reviews
Car inspection station · 216 S San Antonio Ave, Ontario, CA 91762

Mendoza Test Only offers reliable smog check and vehicle inspection services in Ontario, California. View hours and deta...

smog check Vehicle Inspection OBD-II Diagnostics Check Engine Light Diagnosis
CD

California Diesel Compliance DBA THE DPF SHOP

5.0 · 2 reviews
Smog inspection station · 1609 S Grove Ave #110, Ontario, CA 91761

California Diesel Compliance DBA THE DPF SHOP offers emissions testing and smog check in Ontario, California. View hours...

smog check Vehicle Inspection OBD-II Diagnostics Check Engine Light Diagnosis
PO

Porsche Ontario Service Center

5.0 · 640 reviews
Auto repair shop · 2262 Inland Empire Blvd, Ontario, CA 91764

Porsche Ontario Service Center offers emissions testing and smog check services in Ontario, California. View hours and d...

smog check Vehicle Inspection OBD-II Diagnostics Check Engine Light Diagnosis
OS

Ontario Smog Check JC

5.0 · 40 reviews
Smog inspection station · 759 E Holt Blvd, Ontario, CA 91761

Ontario Smog Check JC offers emissions testing and smog check services in Ontario, California. View hours and details.

smog check Vehicle Inspection OBD-II Diagnostics Check Engine Light Diagnosis
CS

California Smog Depot

5.0 · 1 reviews
Smog inspection station · 1141 W Holt Blvd # 2, Ontario, CA 91762

California Smog Depot offers emissions testing and smog check services in Ontario, California. View hours and details.

smog check Vehicle Inspection OBD-II Diagnostics Check Engine Light Diagnosis
SC

Smog Check Coupons

5.0 · 1 reviews
Smog inspection station · 122 E California St, Ontario, CA 91762

Smog Check Coupons offers emissions testing and vehicle inspection services in Ontario, California. View hours and detai...

smog check Vehicle Inspection OBD-II Diagnostics Check Engine Light Diagnosis
V1

Voyager 1 smog

5.0 · 1 reviews
Smog inspection station · 703 S Euclid Ave, Ontario, CA 91762

Voyager 1 smog offers emissions testing and smog check services in Ontario, California. View hours and details on their...

smog check Vehicle Inspection OBD-II Diagnostics Check Engine Light Diagnosis
LA

Los Altos Smog

5.0 · 5 reviews
Smog inspection station · 1409 W Holt Blvd, Ontario, CA 91762

Los Altos Smog offers emissions testing and smog check services in Ontario, California. View hours and details.

smog check Vehicle Inspection OBD-II Diagnostics Check Engine Light Diagnosis
AS

Avid Smog Inc.

5.0 · 7 reviews
Smog inspection station · 1409 W Holt Blvd Unit D1, Ontario, CA 91762

Avid Smog Inc. offers emissions testing and smog check services in Ontario, California. View hours and details for vehic...

smog check Vehicle Inspection OBD-II Diagnostics Check Engine Light Diagnosis
OS

ONTARIO SMOG

4.9 · 113 reviews
Smog inspection station · 152 N Mountain Ave, Ontario, CA 91762

Ontario Smog offers emissions testing and smog check services in Ontario, California. View hours and details for vehicle...

smog check Vehicle Inspection OBD-II Diagnostics Check Engine Light Diagnosis
S&

S & E SMOG CHECK & OIL CHANGE

4.8 · 157 reviews
Smog inspection station · 2235 E 4th St suite h, Ontario, CA 91764

S & E SMOG CHECK & OIL CHANGE offers emissions testing and smog check services in Ontario, California. View hours and de...

smog check Vehicle Inspection OBD-II Diagnostics Check Engine Light Diagnosis

City Guide

Emissions Testing in Ontario, California

Finding a reliable place for emissions testing or a smog check in Ontario is easier than ever. Our directory lists 32 licensed and verified emissions testing stations in the city, including STAR-certified and test-only centers where required. Whether you're renewing your registration or completing an out-of-state transfer, this page helps you quickly locate nearby inspection facilities and understand what applies in California.

Do Vehicles in Ontario Need an Emissions Test?

Most drivers in Ontario follow the same rules set by California. Requirements vary based on vehicle age, fuel type, and county. If you're unsure whether your ZIP code or vehicle model year requires a test, use this directory to browse local stations or review our state-specific testing requirements.

Types of Smog Check Services Available

  • Standard emissions tests for gasoline vehicles
  • OBD-II inspections for 1996+ model years
  • Tailpipe testing for older vehicles where required
  • Diesel emissions testing
  • Hybrid and electric vehicle smog checks
  • Registration renewal support
  • Test-only or STAR-certified inspections (state dependent)

Each listing includes the station's address, contact information, operating hours, and service notes to help you choose the right location.

Smog Check Tips for Ontario Drivers

Before heading to a testing center in Ontario, make sure:

  • Your check engine light is off
  • Your vehicle has completed recent drive cycles
  • The gas cap is properly sealed
  • The engine is fully warmed up
  • You have your registration and ID

Following these steps greatly increases the chance of passing on the first attempt.

Why Use This Directory?

Drivers in Ontario rely on this directory because it provides a complete list of verified emissions testing stations, map-based navigation for quick lookup, accurate state-updated requirements, support for gasoline, diesel, hybrid, and electric vehicles, and clear explanations of exemptions and frequency rules.

View California Requirements

Frequently Asked Questions About Emissions Testing in Ontario, California

Get answers to common questions about smog checks, testing requirements, and finding the right station in Ontario.

You can use this directory to find licensed emissions testing and smog check stations in Ontario. Browse the listings above to see addresses, contact details, and services offered, then choose the station that's most convenient for your part of the city.
It depends on California's emissions testing program, your registration ZIP code, and your vehicle's model year and fuel type. Some areas of California require testing, while others do not. Check your California state page in this directory or your DMV's website to see if your address in Ontario is in a testing area.
Most emissions programs require testing every one or two years, usually tied to registration renewal. Some vehicles are tested more frequently, and others are exempt for the first few model years. Use the California state page to see the current 2025 schedule for your vehicle type and registration area.
Prices vary by station and vehicle, but most emissions tests in Ontario fall within the typical range for California. Many stations list pricing by phone or on their website, and some offer coupons or discounts. Use the listings above to contact a station directly for current pricing.
Requirements depend on vehicle type (gasoline, diesel, hybrid, electric), model year, and weight, as well as where your vehicle is registered in California. In many states, fully electric vehicles are exempt, newer vehicles are temporarily exempt, and certain older or specialty vehicles may have different rules. Check the California state page for the latest 2025 requirements.
Most stations in Ontario ask you to bring your current registration or renewal notice, a valid photo ID, and proof of insurance if required by California. Make sure your vehicle is warmed up and the check engine light is off before you arrive.
If your vehicle fails, the station will provide a report showing the reason for failure (such as stored OBD-II codes or high tailpipe readings). In most programs, you must complete repairs and pass a retest before renewing your registration. Some states offer repair assistance, cost caps, or waivers. Details are listed on the California page in this directory.
In some states, certain vehicles are directed to specific station types (such as STAR or test-only centers). Unless your renewal notice or DMV instructions say otherwise, you can usually choose any licensed station in Ontario. If you're unsure, ask the station when you call or check the instructions on your renewal notice.

Can't find what you're looking for? Contact our customer support team