There are 6 commercial endorsements and 2 restrictions for commercial driver licenses (CDLs). Each endorsement or restriction requires the commercial driver to pass specific tests.
|Endorsement or restriction||Description|
|Passenger endorsement (P)||All passenger endorsements are connected to a vehicle class (Class B or C), depending on the weight of the vehicle:
|School bus endorsement (S)||Required for drivers who operate school buses to transport students to or from school and for school sponsored events.
All school bus endorsements are connected to a vehicle class (Class B or C):
|Double/triple trailers endorsement (T)||Required for drivers pulling sets of double or triple trailers.|
|Tank vehicle endorsement (N)||Required for drivers of vehicles carrying liquids or liquid gases in portable or fixed tanks. This endorsement isn’t required for portable tanks with a rated capacity under 1,000 gallons.|
|Hazardous materials endorsement (H)||Required for drivers of vehicles carrying the types of hazardous materials that require the vehicle to be classified or placarded for hazardous materials. This endorsement requires drivers to be fingerprinted and undergo a federal background check the first time they get an HME, or when they renew or transfer a license from another state.|
|Combination endorsement (X)||This is a combination of a tank and hazardous materials endorsement.|
|Air brake restriction (K)||This is an automatic restriction. If a driver has successfully passed the necessary written and driving tests for air brake equipped vehicles, this endorsement will be removed. Drivers who don’t pass these tests are restricted on the CDL to non-air brake vehicles.|
|Intrastate only restriction (U)||This is for drivers of CDL vehicles who are restricted to driving only within Washington, either because:|