A California emissions programme that checks your truck's onboard diagnostics and reports the result to CARB. It replaced the old roadside smog inspection with a scheduled test you are responsible for submitting.
Nearly every diesel and alternative-fuel vehicle over 14,000 lb GVWR that touches a California public road. That includes trucks registered outside California, and it explicitly includes fleets of one.
For a California-registered vehicle the deadline follows your DMV registration expiration month. For a vehicle registered in another state it follows the last digit of the VIN. Most non-agricultural vehicles now test twice a year rather than once.
File at cleantruckcheck.arb.ca.gov
CARB charges an annual compliance fee per vehicle, indexed to California CPI. The emissions test itself is charged separately by whoever performs it.
Yes. CARB's own guidance covers vehicles registered outside California that operate on California roads. Out-of-state vehicles take their deadline from the last digit of the VIN rather than a DMV registration month.
Yes. CARB's guidance explicitly includes single-vehicle fleets. There is no small-fleet exemption.
Most non-agricultural vehicles are on a twice-a-year compliance schedule. This is the detail carriers most often get wrong, because the programme is frequently described as annual.
CARB places a DMV registration hold on a non-compliant vehicle automatically. The truck cannot be legally registered until compliance is restored.
Annual, plus per-driver queries
Annual
Every 24 months
Quarterly
Annual
Every 90 days
Annual