Question 1

What is Clean Truck Check?

Accepted Answer

California Air Resources Board's (CARB) emissions inspection program for heavy-duty vehicles, also called HD I/M. Covered vehicles must be reported in CTC-VIS, pay an annual fee and pass periodic tests by a CARB-credentialed tester.

Question 2

Which vehicles need Clean Truck Check?

Accepted Answer

Nearly all diesel and alternative-fuel vehicles with a manufacturer GVWR over 14,000 lbs that operate on California roads, including out-of-state, out-of-country, government and personal vehicles. Gasoline vehicles are not covered.

Question 3

Which vehicles are exempt?

Accepted Answer

Zero-emission, emergency, military tactical and historical vehicles; motorhomes registered outside California; vehicles under an experimental permit; new engines certified to the optional 0.01 g/bhp-hr NOx standard (2023–2027 only). There is no low-mileage exemption.

Question 4

How often must a truck be tested in 2026?

Accepted Answer

Twice a year. For California plates the deadlines are the DMV registration expiration date and six months later; other vehicles follow the last digit of the VIN.

Question 5

When does quarterly (4 times a year) testing start?

Accepted Answer

October 2027, for OBD-equipped trucks (diesel 2013+ and alternative fuel 2018+). Not January 1, 2027. Non-OBD trucks stay at twice a year.

Question 6

How early can I test before a deadline?

Accepted Answer

Up to 90 days before the compliance deadline. A test within that window keeps the vehicle compliant through the next deadline.

Question 7

Which vehicles test only once a year?

Accepted Answer

California-registered motorhomes (not used commercially) and agricultural vehicles used only in farming operations.

Question 8

Is there a once-a-year option for low-mileage trucks (SB 1064)?

Accepted Answer

No. SB 1064 would have allowed annual testing for trucks under 1,000 miles a year, but it was vetoed in September 2026.

Question 9

What is the CARB annual compliance fee?

Accepted Answer

$32.13 per vehicle in 2026 and $33.12 per vehicle for deadlines on and after January 1, 2027 (it was $31.18 in 2025). Paid only in CTC-VIS by card or TeleCheck eCheck.

Question 10

How much does a Clean Truck Check test cost?

Accepted Answer

Testers set their own prices. Published California prices are usually $50–$135 per truck for an OBD test and $190–$200 for a smoke opacity test; mobile testers may add a trip fee and often discount fleets.

Question 11

Which test does my truck need?

Accepted Answer

OBD scan for diesel 2013+ and alternative fuel 2018+; smoke opacity (SAE J1667) plus visual inspection for diesel 2012 and older; visual inspection only for alternative fuel 2017 and older.

Question 12

Who can perform a Clean Truck Check test?

Accepted Answer

Only a CARB-credentialed tester. Owners may test their own vehicles only if they are credentialed themselves.

Question 13

How do I find a Clean Truck Check tester near me?

Accepted Answer

CTC Finder lists 2,867 CARB-credentialed testing businesses in California by county, city and ZIP code, 2,543 of them mobile, built from CARB's public tester list (checked November 1, 2026). Listing on CARB's list is optional, so some testers are missing.

Question 14

Is mobile Clean Truck Check testing available?

Accepted Answer

Yes. 2,543 of the 2,867 listed California testing businesses say they come to your yard.

Question 15

Can a Clean Truck Check be done remotely or with telematics?

Accepted Answer

Yes for OBD trucks, if a CARB-credentialed tester runs it with a CARB-certified device. CARB lists 8 certified continuously connected (telematics) device approvals from Geotab, Samsara, Motive, Zonar, Verizon Connect and Pacific Track; tests upload automatically only for credentialed testers' telematics devices. Smoke opacity tests cannot be done remotely.

Question 16

Where do I register a truck for Clean Truck Check?

Accepted Answer

In CARB's CTC-VIS portal at cleantruckcheck.arb.ca.gov. Vehicle changes must be reported within 30 calendar days.

Question 17

How do I get the compliance certificate?

Accepted Answer

Download it from CTC-VIS once the fee has cleared (1–2 business days by card, up to 7 by eCheck) and a passing test is on file. The DMV record can take another 3–5 business days.

Question 18

What is the penalty for not complying?

Accepted Answer

DMV registration holds (SB 210 / Q212), notices of violation and civil penalties of up to $10,000 per day per vehicle under Health and Safety Code § 42402. Tampering can cost up to $37,500 per violation.

Question 19

How does CARB find non-compliant trucks?

Accepted Answer

Roadside Remote Emissions Monitoring Devices (REMD) and license-plate readers, used since January 2023. A flagged truck gets a Notice to Submit to Testing and has 30 days to pass a test.

Question 20

Do out-of-state trucks need Clean Truck Check?

Accepted Answer

Yes, according to CARB, whenever they operate in California. EPA approved the rule into the state plan only for in-state vehicles in January 2026, but CARB says it still enforces it for all vehicles.

Question 21

Can a tester outside California do the test?

Accepted Answer

Yes, if they are CARB-credentialed. CARB's list includes 506 credentialed testing businesses outside California.

Question 22

How do I contact CARB about Clean Truck Check?

Accepted Answer

Hotline (866) 634-3735, email HDIM@arb.ca.gov. CTC Finder is independent and not affiliated with CARB.

Question	Answer	Details
What is Clean Truck Check?	California Air Resources Board's (CARB) emissions inspection program for heavy-duty vehicles, also called HD I/M. Covered vehicles must be reported in CTC-VIS, pay an annual fee and pass periodic tests by a CARB-credentialed tester. Source	Read more
Which vehicles need Clean Truck Check?	Nearly all diesel and alternative-fuel vehicles with a manufacturer GVWR over 14,000 lbs that operate on California roads, including out-of-state, out-of-country, government and personal vehicles. Gasoline vehicles are not covered. Source	Read more
Which vehicles are exempt?	Zero-emission, emergency, military tactical and historical vehicles; motorhomes registered outside California; vehicles under an experimental permit; new engines certified to the optional 0.01 g/bhp-hr NOx standard (2023–2027 only). There is no low-mileage exemption. Source	Read more

Question	Answer	Details
How often must a truck be tested in 2026?	Twice a year. For California plates the deadlines are the DMV registration expiration date and six months later; other vehicles follow the last digit of the VIN. Source	Read more
When does quarterly (4 times a year) testing start?	October 2027, for OBD-equipped trucks (diesel 2013+ and alternative fuel 2018+). Not January 1, 2027. Non-OBD trucks stay at twice a year. Source	Read more
How early can I test before a deadline?	Up to 90 days before the compliance deadline. A test within that window keeps the vehicle compliant through the next deadline. Source	Read more
Which vehicles test only once a year?	California-registered motorhomes (not used commercially) and agricultural vehicles used only in farming operations. Source	Read more
Is there a once-a-year option for low-mileage trucks (SB 1064)?	No. SB 1064 would have allowed annual testing for trucks under 1,000 miles a year, but it was vetoed in September 2026. Source	Read more

Question	Answer	Details
What is the CARB annual compliance fee?	$32.13 per vehicle in 2026 and $33.12 per vehicle for deadlines on and after January 1, 2027 (it was $31.18 in 2025). Paid only in CTC-VIS by card or TeleCheck eCheck. Source	Read more
How much does a Clean Truck Check test cost?	Testers set their own prices. Published California prices are usually $50–$135 per truck for an OBD test and $190–$200 for a smoke opacity test; mobile testers may add a trip fee and often discount fleets. Source	Read more

Question	Answer	Details
Which test does my truck need?	OBD scan for diesel 2013+ and alternative fuel 2018+; smoke opacity (SAE J1667) plus visual inspection for diesel 2012 and older; visual inspection only for alternative fuel 2017 and older. Source	Read more
Who can perform a Clean Truck Check test?	Only a CARB-credentialed tester. Owners may test their own vehicles only if they are credentialed themselves. Source	Read more
How do I find a Clean Truck Check tester near me?	CTC Finder lists 2,867 CARB-credentialed testing businesses in California by county, city and ZIP code, 2,543 of them mobile, built from CARB's public tester list (checked November 1, 2026). Listing on CARB's list is optional, so some testers are missing. Source	Read more
Is mobile Clean Truck Check testing available?	Yes. 2,543 of the 2,867 listed California testing businesses say they come to your yard. Source	Read more
Can a Clean Truck Check be done remotely or with telematics?	Yes for OBD trucks, if a CARB-credentialed tester runs it with a CARB-certified device. CARB lists 8 certified continuously connected (telematics) device approvals from Geotab, Samsara, Motive, Zonar, Verizon Connect and Pacific Track; tests upload automatically only for credentialed testers' telematics devices. Smoke opacity tests cannot be done remotely. Source	Read more

Question	Answer	Details
Where do I register a truck for Clean Truck Check?	In CARB's CTC-VIS portal at cleantruckcheck.arb.ca.gov. Vehicle changes must be reported within 30 calendar days. Source	Read more
How do I get the compliance certificate?	Download it from CTC-VIS once the fee has cleared (1–2 business days by card, up to 7 by eCheck) and a passing test is on file. The DMV record can take another 3–5 business days. Source	Read more

Clean Truck Check key facts

Basics

Deadlines

Cost

Testing

Registration

Enforcement

Out of state

Contacts