CDL Classifications:
A, B, and C Licenses Covered

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What is a Commercial Driver’s License (CDL)?

If you long for a career on the road rather than in an office, you’ll most likely need a commercial driver’s license. Since 1986, drivers have been required to get a commercial driver’s license (CDL) to drive commercial motor vehicles (CMVs) such as tractor-trailers, semi-trucks, dump trucks, and passenger buses. There are three classes of CDLs that determine the kinds of vehicles you’re permitted to drive: Class A, Class B, and Class C. CDL classification is also determined by the vehicle's gross vehicle weight rating (GVWR) and other specific requirements.

It takes highly specialized knowledge and skills to operate a commercial motor vehicle. But prior to 1986, many states allowed anyone with an automobile driver license to operate a CMV. As a result, many drivers throughout the country were driving CMVs without proper training. On October 27, 1986, the Commercial Motor Vehicle Safety Act was signed into law. This law made it mandatory for all drivers of commercial vehicles to have a CDL. By ensuring that bus drivers and operators of large trucks are highly trained and qualified, this law has improved highway safety significantly.

How to Get a CDL

The minimum age to apply for a CDL is typically 21. However, some states allow drivers between the ages of 18 and 20 to apply for a single-state CDL. A single-state CDL allows the driver to only operate a commercial vehicle within the driver’s state of residence (intrastate driving). When the driver turns 21, that restriction is automatically removed.

You can apply for a CDL at a local DMV office. There are strict federal guidelines for obtaining a CDL, and each state has its own requirements that need to be also met. You must pass both a written knowledge exam and a driving skills test, which are designed by your state.

To drive certain specialized types of vehicles such as buses or tank trucks or carry hazardous materials, you must also apply for the proper endorsements on your CDL. Endorsements include Passenger (P), allowing you to carry passengers; Tank (T), allowing you to drive trucks containing liquid cargo; and H (Hazardous Materials), allowing you to drive trucks containing such hazardous materials as flammable liquids, explosives, or radioactive substances. To obtain an endorsement, you will need to pass a specialized knowledge exam and possibly a specialized driving skills test. To obtain a School Bus (S) endorsement, you must also undergo a thorough background check.

Below is a list of all Commercial Driver’s License classes.

  1. 1

    Class A CDL

    You must have a Class A CDL to operate a combination vehicle with a GVWR of 26,001 or more pounds, provided the GVWR of the vehicle(s) being towed exceeds 10,000 pounds.

    With a Class A CDL and the proper endorsements, you may drive the following types of vehicles:

    • Tractor-trailers
    • Truck and trailer combinations
    • Tank vehicles
    • Livestock carriers
    • Flatbeds

    tractor trailer
    Tractor semi truck with flatbed trailer (image credit)

    With the proper endorsements, your Class A CDL may also allow you to drive some Class B and Class C vehicles.

  2. 2

    Class B CDL

    You must have a Class B CDL to operate a single vehicle with a GVWR of 26,001 or more pounds, or tow a vehicle whose GVWR does not exceed 10,000 pounds.

    With a Class B CDL and the appropriate endorsements, you may drive the following types of vehicles:

    • Straight trucks
    • Large passenger buses
    • Segmented buses
    • Box trucks
    • Dump trucks with small trailers
    • Tractor-trailers

    Young man entering a HART’s bus
    Young man entering a HART’s passenger bus (image credit)

    With the proper endorsements, your Class B CDL may also allow you to operate some Class C vehicles.

  3. 3

    Class C CDL

    A Class C CDL allows you to operate a vehicle that is designed to transport 16 or more occupants (including you, the driver) or transport hazardous materials (HazMat), materials that are classified as hazardous under federal law.

    With a Class C CDL and the proper endorsements, you may drive the following types of vehicles:

    • Small HazMat vehicles
    • Passenger vans
    • Combination vehicles not covered by Classes A or B

    Tanker truck of Sodium Hydroxide Solution
    HazMat Tanker truck of Sodium Hydroxide Solution (image credit)

Andrei Zakhareuski, Driving-Tests.org Founder
Andrei is a driver with 11+ years of experience and the founder of Driving-Tests.org.

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