Chain Law!

Winter often means snow-covered and icy roads. Experienced truckers know that the lighter the load, the less traction the tires have. But even trucks hauling heavy loads can lose traction in the snow and ice. That’s why many states will put chain law into effect. Chain law requires truckers to put tire chains on their tires in order to gain more traction. Usually, when chains are required for trucks, cars are also required to use chains or snow tires.

Chain law is publicized by road signs and state road condition portals- websites, road condition hotlines, and the like. You’ll usually only see chain law go into effect on mountain passes, but states can require chains on any roadway that encounters dangerous winter travel conditions.

Some states require that truckers carry the minimum required chains through the winter months, even if they aren’t planning to chain up. Many states may allow cables instead of chains, but most will require truckers to carry chains. Cables are generally frowned on for being less effective.

California Chain Law

Road Conditions: 800-427-7623 (in state) or 916-445-7623(out of state)
Cal-Trans: 916-654-5741
California Chain-up Requirements

California does not require truckers to carry chains during certain times of the year. However, when trucks enter a posted “chains required” area, they must be carrying chains. And when chain law is in effect, truckers cannot proceed without chains on their tires. Cal-Trans will set up “truck screening” areas when chains are required to make sure that truckers are carrying the minimum required chains, so that if they need to use chains, they will be able to install them.

Generally, California requires 5-axle trucks to have chains on all tires on the main drive axle, two tires on the other drive axle, and one tire on each side of the trailer- any axle.


California has three Chain Conditions they enforce.

R-1 Chain Law:
Chains are required on all vehicles except passenger vehicles and light-duty trucks under 6,000 pounds gross weight and equipped with snow tires on at least two drive wheels. Chains must be carried by vehicles using snow tires. All vehicles towing trailers must have chains on one drive axle. Trailers with brakes must have chains on at least one axle.

R-2 Chain Law:
Chains are required on all vehicles except four-wheel-drive vehicles under 6,500 pounds gross weight and equipped with snow tires on all four wheels. Chains for one set of drive wheels must be carried by four wheel-drive vehicles using snow tires.