States
California
Ontario

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
ES

Enav Smog Shop

4.4 · 43 reviews
Smog inspection station · 2314 S Vineyard Ave Ste H, Ontario, CA 91761

Enav Smog Shop 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
SS

SAS Star Certified Smog Check Ontario Ca

4.4 · 17 reviews
Smog inspection station · 2209 E 4th St, Ontario, CA 91764

SAS Star Certified Smog Check in Ontario, California offers reliable emissions testing and vehicle inspections. View hou...

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

Ontario Smog Check

4.3 · 85 reviews
Smog inspection station · 5420 W Mission Blvd, Ontario, CA 91762

Ontario Smog Check 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
IN

In N Out Smog Check & Clean Truck Air Check Services

4.3 · 18 reviews
Smog inspection station · 534 S Mountain Ave, Ontario, CA 91762

In N Out Smog Check & Clean Truck Air Check Services offers emissions testing and vehicle inspection in Ontario, Califor...

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

ACE Smog Center

4.2 · 90 reviews
Smog inspection station · 601 E Holt Blvd, Ontario, CA 91761

ACE Smog Center offers emissions testing and smog check services in Ontario, California. View hours and details about th...

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

Low Price Smog Check

4.0 · 104 reviews
Smog inspection station · 2480 S Archibald Ave, Ontario, CA 91761

Low Price Smog Check offers emissions testing and vehicle inspection in Ontario, California. View hours and details.

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

Immanuel Auto Smog Check

4.0 · 50 reviews
Smog inspection station · 817 E Holt Blvd Ste #B, Ontario, CA 91761

Immanuel Auto Smog Check 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
ES

Express Smog Repair

2.8 · 23 reviews
Smog inspection station · 105 W California St, Ontario, CA 91762

Express Smog Repair 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

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