Heavy Duty Trucking Logo
MenuMENU
SearchSEARCH

CARB Clean Truck Check Compliance Begins Jan. 1

Starting January 2024, all trucks driving in California will need proof of compliance with CARB’s Clean Truck Check to continue operating in the state. Operating in California without registration in the compliance database could result in violations from CARB and/or the California Highway Patrol.

CARB Clean Truck Check Compliance Begins Jan. 1

Remote Emissions Monitoring Devices monitor the exhaust emissions of passing heavy-duty vehicles and flag potential high emitters.

Photo: CARB

3 min to read


Beginning on January 1, 2024, all trucks operating in California will need proof of compliance with California Air Resources Board (CARB) regulations to continue operating in the state. Vehicles must be registered in the Clean Truck Check database by Dec. 31.

Clean Truck Check, formerly known as the Heavy-Duty Inspection and Maintenance Program, was approved by CARB in 2021. CARB said the program ensures heavy-duty vehicles operating in California are well-maintained and repaired quickly when needed to reduce emissions and improve public health statewide, especially in disadvantaged communities disproportionately impacted by air pollution.

Ad Loading...

It also provides a level playing field for the businesses that operate these vehicles as it applies to both in-state and out-of-state registered heavy-duty vehicles, according to CARB.

The program includes nearly all non-gasoline vehicles with a gross vehicle weight rating over 14,000 pounds that operate in California. This includes public vehicles, trucks, buses, personal vehicles, California-registered motorhomes, single-vehicle fleets, and vehicles registered outside of California (not including motorhomes).

Clean Truck Check is being implemented in three phases.

Ad Loading...

Clean Truck Check rolls out starting in 2023 and into 2024.

Source: CARB

Phase 1 of Clean Truck Check

This initial phase, which started Jan. 1, began with the deployment of Remote Emissions Monitoring Devices (REMD).

REMDs monitor the exhaust emissions of passing heavy-duty vehicles and flag potential high emitters that may receive a Notice to Submit to Testing (NST).

NST’s require vehicle owners to submit a passing compliance test to CARB after any necessary emissions-related repairs are made, within 30 days of receipt of the notice. Failure to comply and remedy emissions-related concerns could result in DMV registration holds and/or removal from the compliance database.

Phase 2 of Clean Truck Check

This phase, which started Oct. 1, requires vehicle owners who are subject to the program to enter their vehicles in CARB’s Clean Truck Check database and pay an initial annual compliance fee of $30 dollars per vehicle by December 31.

Phase 2 also includes freight contractor, broker, and applicable freight facility requirements for hiring compliant fleets, allowing access to the facility, and record keeping.

Ad Loading...

Starting January 2024, all trucks driving in California will need proof of compliance with these requirements to continue operating in the state. Operating in California without registration in the compliance database could result in violations from CARB and/or the California Highway Patrol.

Phase 3 of Clean Truck Check

Phase 3 of Clean Truck Check requires heavy-duty vehicle owners to conduct periodic emissions testing on their vehicles.

This is similar to California’s Smog Check program for cars, according to CARB.

Periodic testing begins in 2024 and applies to all compliance deadlines after July 1, 2024.

Compliant tests may be submitted as early as April 2024. Periodic testing initially will be required twice per year for nearly all vehicles in the program.

Ad Loading...

Agricultural vehicles and California-registered motorhomes are required to test once annually. Testing requirements vary based on whether the vehicle is equipped with onboard diagnostics (OBD).

CARB reports Clean Truck Check will save more than 7,500 lives and prevent 2,500 hospital visits. 

Source: CARB

For California-registered vehicles, the compliance testing deadlines are linked to each vehicle’s DMV registration expiration/renewal date.

For vehicles registered outside of California and for vehicles exempt from DMV registration requirements, compliance deadlines are based on the last number of a vehicle’s VIN.

Passing test results may be submitted up to 90 days before a compliance deadline. Testing should be performed in a timely manner to avoid penalties and possible DMV registration holds.

A truck passes an emissions monitoring station in California.

Photo: CARB

More Safety & Compliance

Winter pileup accidents.
Disaster Responseby Jack RobertsApril 30, 2026

Avoiding Winter Pileups: Don’t Become the Next Link in the Crash-Chain

Winter roadway “pileups” aren’t one crash — they’re a chain reaction. Here’s what triggers them, how truck drivers can spot the danger early, and what to do if you're suddenly trapped in the mess.

Read More →
Mobile tablet showing Motus screen against highway background with Motus logo

FMCSA’s Motus System Is Coming. What Fleets Need to Know Now

The long-awaited registration system promises a single portal — and tighter fraud controls.

Read More →
Graphic with light bulbs, HDT Truck Fleet Innovators logo, and the word Nominations
Fleet ManagementApril 24, 2026

Nominations Open for HDT Truck Fleet Innovators 2026

Heavy Duty Trucking is searching for forward-looking leaders at trucking fleets as nominations for HDT’s Truck Fleet Innovators 2026. Deadline is May 15.

Read More →
Ad Loading...
Detroit ABA6 safety system.

Freightliner Expands Detroit Assurance with New Intersection and Turning Safety Tech

Detroit’s next-generation ABA6 safety system adds cross-traffic detection and enhanced side guard assist with left-turn protection, targeting high-risk urban scenarios.

Read More →
Illustration with ATRI logo and square blocks spelling out "research"
Fleet Managementby Deborah LockridgeApril 20, 2026

'Beyond Compliance,' Regulations, Driver Coaching on ATRI’s 2026 Research List

The American Transportation Research Institute will examine driver coaching, regulatory impacts — including the "Beyond Compliance" concept —and weather disruptions that shape trucking operations.

Read More →
Illustration of colorful map of United States with DataQs website screen superimposed

FMCSA Revamps DataQs to Improve Fairness, Speed of Reviews

New requirements add firm deadlines and independent review steps, addressing long-standing complaints about inconsistent rulings and slow response times.

Read More →
Ad Loading...
Illustration of driver medical exam paperwork over duotone background of a blood pressure check

FMCSA Extends Paper Medical Card Exemption … Again

Five states still aren't ready to accept commercial driver medical exam information directly from the medical examiner's registry.

Read More →
Collage of Top 20 Product award ceremonies
EquipmentMarch 31, 2026

HDT Honors the Best New Products of 2025 at TMC [Photos]

Heavy Duty Trucking's Top 20 Products awards recognize the best new products and technologies. Check out the award presentations at the 2026 Technology & Maintenance Council annual meeting.

Read More →
freightliner whitepaper
SponsoredMarch 31, 2026

Detroit Engines: Trusted Performance, Built for What's Next

The Detroit® Gen 6 engine platform proves that real progress doesn’t require a complete redesign. Built on 20 years of trusted technology, these engines are designed for efficiency, stronger performance, and greater reliability than before. And they do it all while complying with 2027 EPA standards on every mile.

Read More →
Ad Loading...
Aperia HALO front steer axle.
Safety & Complianceby Jack RobertsMarch 18, 2026

Aperia Expands Halo Platform with Steer-Tire Inflation System, Fifth-Wheel Integration

Aperia Technologies introduced a new automatic tire inflation system for steer axles and a partnership with Fontaine Fifth Wheel to integrate coupling status into its Halo Connect platform.

Read More →