CARB Clean Truck Check Compliance Information

Who must comply

Clean Truck Check applies to almost every non-gasoline vehicle over 14,000 pounds GVWR that operates in California. The rule is operation-based, not registration-based, which means out-of-state and out-of-country carriers are equally subject once their trucks cross into California.

• Diesel heavy-duty vehicles > 14,000 lb GVWR. The bulk of the program. On-highway tractors, vocational trucks (dump trucks, concrete mixers, vacuum trucks), and similar.
• Heavy-duty alternative-fuel vehicles. CNG, LNG, propane, and certain hybrid drivetrains are covered. Battery-electric vehicles have their own compliance handling that effectively reduces to recordkeeping rather than emissions testing.
• California-registered motorhomes > 14,000 lb GVWR. Included under the motorhome subprogram with its own test workflow.
• Out-of-state and out-of-country carriers operating in California.Same rule. CARB's jurisdiction attaches to operation in California, not registration.

What's notcovered: gasoline-powered vehicles, vehicles under 14,000 lb GVWR (most pickup trucks and vans), government-owned vehicles under separate program coverage, and vehicles that don't operate in California. A truck registered in Nevada that never crosses the state line isn't subject to Clean Truck Check.

Testing cadence

Each subject vehicle has an assigned compliance deadline. The owner must have a passing compliance test on file in CTC-VIS against that deadline. Currently — through 2027 — the cadence is biannual, meaning two passing tests per year per vehicle, scheduled against two annual deadlines.

Starting with compliance deadlines in 2028 and after, the cadence shifts to quarterly— four passing tests per year per vehicle. Because every deadline has a 90-day testing window that opens before the deadline date, quarterly cadence starts to execute in Q4 2027 for fleets with Q1 2028 deadlines. The rule is technically "2028", but the operational change shows up in fleets' 2027 calendars. We have a deeper treatment on the 2027 testing changes page.

Testing can be satisfied three ways: by visiting a CARB-credentialed in-shop tester, by hiring a credentialed mobile tester to come to your yard, or by running an Clean Truck Check device device that submits tests automatically during normal vehicle operation. CARB credentials the tester (the person + their equipment), not the location — so an in-shop test, a mobile test, and an remotely-submitted test are equally valid compliance events. See the testing options comparison for which approach fits which fleet profile.

Fees and certificates

Two costs apply to each subject vehicle each year:

1. The annual CTC-VIS compliance fee. Paid through your CTC-VIS account at cleantruckcheck.arb.ca.gov. The fee is set by CARB rule, not by the tester or any third party. You pay it once per vehicle per compliance year.
2. The cost of the actual test. Paid to the CARB-credentialed tester. In-shop rates run $90-$300 per test in mid-2026; mobile rates $120-$350; Clean Truck Check device subscription prices are a flat per-vehicle rate that covers all tests within the subscription term, including retests.

Once the annual fee is paid and a passing test is on file, CTC-VIS issues a downloadable compliance certificate. The certificate must be retained as proof of compliance and should be kept in the vehicle's document binder for roadside enforcement encounters. CTC-VIS keeps a digital record, but having a physical copy on the truck protects against any database lookup issues during a roadside stop.

For step-by-step instructions on the CTC-VIS workflow — account creation, vehicle addition, fee payment, certificate download — see our CTC-VIS account setup walkthrough.

If a vehicle is non-compliant — missed deadline, missing test, unpaid fee — CARB flags the vehicle in the DMV registration system. That flag can trigger a registration hold at renewal and raises the practical risk of roadside enforcement. The remedy in every case is the same: resolve the underlying issue in CTC-VIS (pay the fee, submit a passing test, address the failed test) and the flag clears on the next CTC-VIS cycle.

Finding a tester

CTC Directory maintains a searchable list of every CARB-credentialed Clean Truck Check tester in the program. The list is rebuilt weekly from CARB's public CTC-VIS tester database so credentials lapse and additions flow through automatically.

Three ways to find one:

• Search by city or ZIP — the fastest path if you know where you need testing.
• Browse by state — every state with credentialed testers has its own hub page.
• For Southern California specifically, Clean Truck Check Pro (CTCP) runs mobile testing across LA Basin, Inland Empire, and San Diego. For nationwide Clean Truck Check device subscription testing, Smart CTC covers US, Canada, and Mexico. (Disclosure: both are operated by the team that runs this directory. The directory also surfaces every other credentialed tester with equal prominence on the state and city pages.)

California fleets typically start with the California state hub. Out-of-state fleets crossing into California — looking for a tester on their California route — can find their target state or California region from the site map.