CDL Classes: A, B, and C Explained
Every US commercial driver’s license falls into one of three federally defined classes — A, B, or C — set by vehicle weight rating, not by state. Every state issues the same three classes under the same federal definitions; what varies by state is the fee, the testing process, and which third-party testers (if any) are allowed.
Deciding which class you need is the first real fork in the path to a CDL — it determines which vehicles you can drive and which endorsements even apply to you.
Class A — Combination vehicle
- Federal weight threshold
- A combination of vehicles with a gross combination weight rating (GCWR) of 26,001 lbs or more, provided the vehicle(s) being towed have a gross vehicle weight rating (GVWR) over 10,000 lbs.
- What it permits
- The broadest class — a Class A holder may also operate a Class B or Class C vehicle, provided they hold any endorsement that vehicle requires.
- Typical vehicles
- Tractor-trailers, tanker trucks, livestock carriers, and flatbeds towing a heavy trailer.
Class B — Heavy straight vehicle
- Federal weight threshold
- A single vehicle with a GVWR of 26,001 lbs or more, or that same vehicle towing a trailer weighing 10,000 lbs GVWR or less.
- What it permits
- A Class B holder may also operate a Class C vehicle, provided they hold any endorsement it requires, but not a Class A combination.
- Typical vehicles
- Straight trucks, dump trucks, box trucks, and large buses that aren't towing a heavy trailer.
Class C — Small vehicle
- Federal weight threshold
- A single vehicle or combination that meets neither the Class A nor Class B weight threshold, but that either is designed to carry 16 or more passengers including the driver, or is used to transport hazardous materials as federally defined.
- What it permits
- The narrowest class — it exists specifically to cover passenger- and hazmat-carrying vehicles too light to fall into Class A or B on weight alone.
- Typical vehicles
- Passenger vans, small buses, and box trucks placarded for hazardous materials.
First-time applicants: check ELDT
Getting a Class A or Class B CDL for the first time, or upgrading an existing Class B to Class A, requires completing Entry-Level Driver Training (ELDT) with an FMCSA-registered provider before the skills test — the same requirement applies to a first-time school bus or passenger endorsement. A first-time hazmat endorsement also requires ELDT, but gates on the knowledge test rather than the skills test. Full ELDT requirements →
By state
Class definitions don’t change state to state, but fees, testing rules, and third-party testing availability do. This covers 51 of the 51 US jurisdictions on record so far.
Browse CDL requirements by state →Class definitions above are drawn directly from 49 CFR §383.91 (eCFR), the federal regulation that sets them, and verified against its current text during this review.