CARB Clean Truck Check Compliance Checker
Check whether your truck is subject to California's Clean Truck Check program.
Based on CARB's published Clean Truck Check rules for vehicles over 14,000 lbs GVWR operating in California. Confirm your specific vehicle's status in CARB's CTC-VIS system.
Get More Out of the CARB Compliance Checker
Applies Based on Where You Operate, Not Where You're Registered
Clean Truck Check applies to vehicles operating in California above the GVWR threshold, regardless of where the truck is titled or where the operating company is based.
Testing Method Depends on Engine Type and Age
Newer diesel engines with onboard diagnostics get a faster OBD data check; older or non-OBD-equipped vehicles go through a smoke opacity test instead.
The Testing Frequency Is About to Double
Starting October 2027, OBD-tested vehicles move from two tests a year to four, a meaningful increase in compliance overhead worth planning for now rather than after it takes effect.
CARB Compliance Checker: Formula, Benchmarks, and a Worked Example
California's Clean Truck Check program applies to a lot of trucks that operate in the state even occasionally, and the testing frequency is about to change for diesel vehicles with onboard diagnostics. This calculator checks whether your truck is subject to the program, which testing method applies, and what the annual fee runs, based on your truck's GVWR, model year, and engine type.
Who the Program Actually Applies To
California's Clean Truck Check program applies to heavy-duty vehicles with a gross vehicle weight rating over 14,000 pounds that operate in California, whether or not the vehicle is registered there. If your truck is above that weight threshold and runs any routes into or through California, the program applies to you, which catches a lot of out-of-state trucking operations that might not expect to be in scope.
Two Different Testing Methods
Vehicles with a 2013-or-newer diesel engine equipped with onboard diagnostics go through an OBD data check, a faster, electronic pull of the engine's emissions data. Vehicles without that OBD capability, generally older diesels or certain other configurations, go through a smoke opacity test instead, a more traditional tailpipe emissions measurement. Which method applies to your truck depends entirely on the engine's model year and whether it has OBD.
The Testing Frequency Change Coming in 2027
In 2026, most vehicles subject to the program test twice a year. Starting October 2027, vehicles tested through the OBD method move to four tests a year, doubling the compliance burden for exactly the newer, OBD-equipped diesel trucks the program is designed around. Vehicles using the smoke opacity test aren't affected by this specific change. Planning for the increased frequency now, rather than scrambling when it takes effect, keeps a fleet from falling out of compliance.
What the Annual Fee Actually Costs
The Clean Truck Check annual compliance fee is $32.13 for 2026, rising to $33.12 for fee deadlines falling on or after January 1, 2027. It's a modest per-vehicle cost on its own, but it adds up across a fleet and is worth budgeting for alongside the testing itself, since missing either the fee or a required test can result in being flagged non-compliant.
What Happens If You're Not Compliant
A non-compliant vehicle can face restrictions on registration renewal and potential citations when operating in California, and the state has been actively expanding enforcement of the program. If this calculator shows your truck is subject to the program, the practical next step is registering with CARB's Clean Truck Check system directly and scheduling your required testing before a deadline catches you off guard.
Related Calculators
IFTA Calculator
Calculate your quarterly IFTA fuel tax by state.
Try it free →Tax Calculator
Estimate self-employment and income tax as an owner-operator.
Try it free →Per Diem Calculator
Calculate your per diem deduction for days on the road.
Try it free →HOS Calculator
Track your 11/14/70-hour HOS clocks.
Try it free →