Class A vs Class B vs Class C CDL: What Is the Difference?
TL;DR
The class comes from weight and what you tow. Class A is a combination of 26,001 lbs or more with a towed unit over 10,000 lbs. Class B is a single vehicle of 26,001 lbs or more. Class C covers smaller vehicles that carry 16 or more people or hazardous materials, per 49 CFR 383.91.
Class A: heavy combinations
49 CFR 383.91 defines Group A as any combination of vehicles with a gross combination weight rating (GCWR) of 26,001 pounds or more, provided the GVWR of the vehicle being towed is over 10,000 pounds. That is the tractor-trailer. Both numbers matter: the combination has to reach 26,001 lbs and the towed unit has to exceed 10,000 lbs. Our Class A page covers what the license opens up.
Class B: heavy straight vehicles
Group B is any single vehicle with a GVWR of 26,001 pounds or more, or any such vehicle towing a vehicle that is not over 10,000 pounds GVWR (49 CFR 383.91). So a heavy single-unit truck qualifies, and it can pull a light trailer of 10,000 lbs or less without moving you into Class A. Pull something heavier and the combination becomes a Class A matter. GVWR is the manufacturer's rating for the loaded weight of a single vehicle, per 49 CFR 383.5.
Class C: smaller vehicles with a special load
Group C is a single vehicle or combination that meets neither the Group A nor the Group B definition, but that either is designed to transport 16 or more passengers including the driver, or is used to transport hazardous materials (49 CFR 383.91). Weight alone does not make something Class C. A smaller vehicle only needs a CDL when it carries 16 or more people or hazmat. The definition of a commercial motor vehicle in 49 CFR 383.5 also covers small vehicles designed for 16 or more passengers or used to transport hazardous materials.
The three classes side by side
Using the thresholds in 49 CFR 383.91:
- Class A: combination with GCWR of 26,001 lbs or more, and the towed vehicle's GVWR over 10,000 lbs.
- Class B: single vehicle with GVWR of 26,001 lbs or more, or towing a vehicle of 10,000 lbs GVWR or less.
- Class C: does not meet A or B, but is designed for 16 or more passengers including the driver, or carries hazardous materials.
How testing fits the class
You test for the class you plan to drive. 49 CFR 383.113 requires the basic vehicle control skills to be shown for the vehicle class the driver operates or expects to operate, and the skills test has the same three parts for every class: pre-trip inspection, basic control and on-road driving. Endorsements such as hazmat or passenger can add further knowledge tests. Your state sets fees and scheduling, so confirm details with your state licensing agency.
Practice the CDL general knowledge questions →