What Are the Carb States and What Does Carb Compliant Mean?

Imagine that you’re living in Los Angeles in the 1940s. You leave your home to go to the market, but you can barely see your surrounding environment due to an influx of smog. You can only see three blocks ahead of you. You feel the piercing, burning pain in your eyes and feel unwell taking in whatever is in the air. You wonder if there is a chemical attack or something else, but whatever it is, it’s not pleasant and affecting your environment (literally). 

While this may sound like some sort of fiction, this actually happened in 1943 in Los Angeles. After thinking it was a nearby plant causing the problem, it was later realized that smog from cars was the primary culprit. That incident caused a domino effect in Los Angeles with the city creating the Los Angeles County Air Pollution Control District and by 1967 establishing the California Air Resources Board (CARB). Now, California has some of the strictest requirements when it comes to smog and emissions, thanks to CARB. As a driver, you may come across this term and wonder what is CARB and what does CARB compliant mean? We’ve broken it down for you in this brief guide. 

What CARB and CARB Compliant Actually Means | Metromile

What does CARB refer to? 

If you’ve seen the acronym CARB related to cars, you probably understand it’s not related to carbs like pasta or bread. CARB refers to the California Air Resources Board and is the state of California’s agency that was created to help combat air pollution in 1967. 

What’s important to note is that California has been a leader in combatting the effects of air pollution and is a trailblazer in the field. The federal Clean Air Act noticed California’s efforts and aimed to reduce air pollution on a national level — while giving California the ability to set its own unique and even stricter standards for emission regulations. 

Since its inception, CARB has done many notable things to reduce emissions including:

  • Setting the nation’s first tailpipe emission standards
  • Creating nationwide standards related to vehicle greenhouse gas emissions
  • Regulations related to manufacturers creating more zero-emission vehicles (ZEV)
  • Eliminating lead in gasoline 
  • Creating new standards for clean-burning fuel 

On top of that, CARB was given the responsibility of monitoring and reducing greenhouse gas emissions that affect climate change in the 2000s. As you can see, the agency has done a lot to help the state of California and is a leader on the national stage when it comes to setting standards related to air pollution. 

What is CARB compliant?

The state agency CARB recently made changes where certain vehicles must be deemed ‘CARB compliant’. But what is carb compliant, exactly?

As of 2020, the Department of Motor Vehicles, in collaboration with CARB, began verifying compliance with certain vehicles to ensure certain standards were met. It is specifically related to a Truck and Bus Regulation to get emissions up-to-date to current standards. 

This is geared toward diesel trucks and buses, so not necessarily the everyday passenger car. To become CARB compliant, drivers must replace their 2010 or older trucks or buses or use an acceptable alternative while reporting as part of the Truck Regulation Upload, Compliance and Reporting System (TRUCRS).

If you need to become CARB compliant and don’t, the DMV may place a hold on your registration. Additionally, if you need assistance to make that happen there are CARB compliant funding programs that can help you out listed here. 

CARB compliant can also refer to other things that are not motor vehicles such as generators, lawnmowers, leaf blowers, and other types of power equipment. CARB has specific regulations for those items to help reduce pollution. 

Which states are considered CARB states? 

While CARB refers to the California Air Resources Board, other states have joined forces to adopt similar emission standards in their own states. As noted above, California has the ability to set stricter standards and other states are following suit with their own clean air programs. 

Currently, there are 14 other CARB states plus the District of Columbia that have adopted California’s emission standards. The CARB states (aside from California) include:

  1. Colorado
  2. Connecticut
  3. Delaware
  4. Maine
  5. Maryland
  6. Massachusetts
  7. New Jersey
  8. New York 
  9. Oregon
  10. Pennsylvania
  11. Rhode Island
  12. Vermont
  13. Virginia 
  14. Washington 
  15. Washington D.C. 

There are other states such as Minnesota, New Mexico, as well as Nevada that are working toward passing legislation to become CARB states. 


CARB refers to the California Air Resources Board whereas the EPA refers to the Environmental Protection Agency. Both entities work toward reducing air pollution and emissions but have some differences. 

CARB is the state agency in California and the EPA is the federal agency overseeing things nationwide. As noted previously, CARB can have even tougher requirements than the EPA though. California and other CARB states must abide by CARB compliance, whereas other states would have to defer to the emission standards set by the EPA. 

The bottom line 

If you see the term CARB or have a requirement to become CARB compliant, now you have an idea of what it all means. The state agency has paved the way for other CARB states to reduce air pollution and emissions and create a world that is healthier and safer for you and the environment. 

If you’re a low-mileage driver, see how you can reduce emissions and save money with pay-per-mile auto insurance through Metromile. Grab a free quote to see how much you could save. 

Melanie Lockert is a freelance writer, podcast host of the Mental Health and Wealth show, and author of Dear Debt. She’s a cat mom to two jazzy cats, Miles and Thelonious, an amateur boxer, music lover, and needs coffee to function.