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Clean Truck Check Directory
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Compliance Deadlines

When is your Clean Truck Check due?

Clean Truck Check uses recurring compliance windows tied to your vehicle. Miss the window and you risk non-compliance fees and registration holds.

Who is covered

  • Most non-gasoline heavy-duty vehicles operating in California with a GVWR over 14,000 lbs.
  • Includes in-state and out-of-state vehicles that operate in California.
  • Specific motor home, agricultural, and emergency exemptions may apply.

Submission frequency

Vehicles that meet the OBD test requirements typically need to submit more frequently than vehicles tested via smoke opacity. CARB publishes the cadence for each compliance cycle, including initial onboarding deadlines and ongoing renewals.

What triggers a fee

  • Failure to complete a required test within the compliance window.
  • Vehicle unable to communicate with the OBD tester (and no smoke opacity submitted as backup where required).
  • Continued non-compliance after notice.

How to stay ahead

  • Log into your CARB CTC account and bookmark your next due date.
  • Schedule with a Certified Tester before the last week of the window.
  • If you have many trucks, stagger testing and use a fleet tracker.
Not a substitute for CARB guidance. CTC Connect publishes plain-English explanations of publicly available compliance information. Always verify rules with the official CARB Clean Truck Check program. Need a Certified Tester? Search the directory.