Washington clean car standards

Transportation is the largest source of carbon pollution in Washington, accounting for almost 45% of total emissions in the state. Under the Clean Cars Law, new vehicles sold in Washington have to meet the strictest emission standards in the country to protect people's health. Vehicle pollution causes health problems, such as cancer and asthma, and also contributes to climate change.

Zero emission vehicle standards

On March 25, 2020, Gov. Jay Inslee signed the Motor Vehicle Emission Standards – Zero Emission Vehicles (ZEV) bill. This bill directs Ecology to adopt California vehicle emission standards, including zero emission vehicle standards that require a percentage of the vehicles sold in Washington to be zero emission.

Ecology plans to start this rulemaking June 22 at the rule proposal stage. The rulemaking will include:

  • Zero-emission vehicles for passenger cars, light-duty trucks, and medium-duty vehicles
  • Zero-emission vehicles for medium- and heavy-duty trucks (Advanced Clean Trucks)
  • Low-emission vehicle requirements for medium-duty vehicles

As part of the rulemaking, Ecology will be holding two online public information sessions:

For questions on the rulemaking, contact Elena Guilfoil, or 360-972-5166.

Committed to cleaner vehicles

In 2005, the Legislature adopted the Clean Car Law, requiring new cars to comply with California vehicle emission standards starting in 2009. Since 1971, California has had a waiver under the federal Clean Air Act to set emission standards that are more protective than the national standards set by EPA. The federal Clean Air Act allows states to adopt the federal standards or California's standards. Washington is one of 14 states, plus the District of Columbia, that chooses to follow California’s lead.

In 2018, EPA proposed to weaken the national vehicle emission standards by freezing emission improvements for model years 2021 through 2025. California adopted more protective standards.

In December 2018, we updated our low emission vehicles rule to keep Washington in line with California, making sure that vehicles sold in Washington continue to meet the more protective emission standards. This rule regulates cars and light-duty trucks. New vehicles that do not meet Washington's vehicle emission standards cannot be registered, licensed, rented, or sold here — even if they meet federal standards. It is your responsibility to make sure your car meets the state standards.

Buying a car in Washington

If you buy a new car in Washington, then you can register it in Washington. Washington car dealers must sell vehicles that meet California's vehicle emission standards. If you buy a car with less than 7,500 miles that doesn't meet the California standards, then you can't register it in Washington. If you a buy a car with more than 7,500 miles, then you can register it in Washington.

Fourteen other states, including Oregon and California, have the same vehicle emission standards. If you buy a  2009 or newer model car in one of those states, it will meet state standards.