Clean Truck Check testers in Ontario, CA

31 testing businesses in Ontario are on CARB's public Clean Truck Check tester list (33 credentialed testers). 30 offer mobile testing at your yard, 15 can do smoke opacity tests for older non-OBD trucks and 24 test motorhomes. Counting nearby cities, 349 listings are within 20 miles.

Testers in Ontario

More testers within 20 miles of Ontario

Trucking in Ontario: what to know

Ontario combines the ONT air-cargo airport with dense distribution-center blocks south of I-10 and along the 60. The Inland Empire holds roughly a billion square feet of warehouse space (Pitzer College estimate), so local fleets and owner-operators run a high volume of tests. Mobile testers who visit distribution centers and truck yards are common here.

San Bernardino County covers most of the Inland Empire warehouse belt (Fontana, Ontario, Rialto, San Bernardino) and the High Desert along I-15. The Inland Empire holds roughly a billion square feet of warehouse space (Pitzer College estimate), so local fleets and owner-operators run a high volume of tests. Mobile testers who visit distribution centers and truck yards are common here.

What a Clean Truck Check costs in Ontario

Testers set their own prices and most do not publish them. Across the California prices we found, an OBD test usually costs $50–$135 per vehicle and a smoke opacity test $190–$200. Mobile testers in Ontario may add a trip fee but often discount fleets that test several trucks at once. How prices compare.

Frequently asked questions

How many Clean Truck Check testers are in Ontario?

CTC Finder lists 31 testing businesses in Ontario from CARB's public tester list (33 credentialed testers), last checked November 1, 2026. Listing on CARB's list is optional, so the real number can be higher.

Is there mobile Clean Truck Check testing in Ontario?

Yes. 30 listed businesses in Ontario offer mobile testing, which means the tester comes to your yard. Use the Mobile filter above to see them.

How much does a Clean Truck Check test cost in Ontario?

Testers set their own prices. Published prices for an OBD test are usually $50–$135 per vehicle; smoke opacity tests for older trucks often cost more, and mobile testers may add a trip fee. See the cost guide.

How often does my truck need a Clean Truck Check test?

Most trucks test twice a year, on a schedule tied to the DMV registration expiration date. CARB says OBD trucks move to four tests a year beginning October 2027. California-registered (non-commercial) motorhomes and agricultural vehicles test once a year. See the deadline guide.

Source: CARB's public Clean Truck Check tester list, last checked . Listing on CARB's list is optional for testers, so some credentialed testers are not shown. Services, hours and prices change; please confirm with the tester before you go. Something wrong? Send a correction.