Studded tires

Studded tires are only legal Nov. 1 - Mar. 31. Motorists using studded tires before or after these dates could incur a fine from law enforcement. Approved studded tires & chains

There is no individual exception to the studded tire season. When traveling in Washington, you are required to follow the State of Washington's motor vehicle laws.

Studded tires do not satisfy state chain requirements. If chains are required on your vehicle, you'll have to install them even on studded tires.

Motorists are encouraged to visit a tire dealer to learn more about stud-free winter traction tires that are legal for year-round use and do not cause the same roadway damage as studded tires. These tires are different from "all season" tires and have a more aggressive tire tread.

See more about studded tires and other pavement research from the WSDOT Materials Laboratory.

Traction tires

The following qualify as traction tires when required on Washington roadways:

Approved traction tires - including an eighth of an inch tread and a M&S or All Season label or a Mountain/Snowflake symbol.

Installing chains makes any tire a traction tire. Approved tire chains

Chains and alternatives

Those traveling into higher elevations should carry chains and have approved traction tires whenever winter weather is possible, especially Nov. 1 through March 31.

Studded tires do NOT satisfy state chain requirements; if chains are required, they'll have to installed on top of studded tires.

4WD/AWD and chains

4WD/AWD vehicles (under 10,000 pounds) do not need chains installed during "chains required" notices, but drivers still must carry chains with them in case conditions worsen and they're required to install chains during a "chains required on all vehicles" notice.

Chain placement

Front- and rear-wheel drive vehicles

On a front-wheel drive vehicle you must install chains on the front two tires. On a rear-wheel drive vehicle, you must install chains on the rear two tires.

Commercial vehicles/trailers

Consult Commercial vehicles chain requirements

Non-commercial vehicles and trailers, RVs, etc.

Vehicle, trailer and load combinations that are under 10,000 pounds must follow regular chain requirements. If the non-commercial vehicle and trailer combined are under 10,000 pounds, the law only requires the pulling vehicle to be chained when "chains required" is posted, though drivers can install chains on both the pulling vehicle and the trailer if they wish to.

Vehicle, trailer and load combinations that are more than 10,000 pounds must chain up when "chains required" is posted - even if 4WD/AWD. Consult Commercial vehicles chain requirements for chain placement for vehicle and trailer - which is required based on weight not type of vehicle.

Alternative traction devices

Some vehicles cannot accommodate chains and must use one of the WSP-approved "alternative traction devices" to satisfy chain requirements on vehicles with five or less axels. These textile tire covers are also called "snow socks." For more details, visit the Washington State Patrol's Vehicle and Equipment Requirements page under the "traction tires" section.

Stevens Pass and Snoqualmie Pass map of chain up and off areas (PDF 50 KB)

Traction and chain requirements