CDL Requirements by Class

Updated 10 min read

Part of Driver Files & Medical

49 CFR §383.91(a)

Three vehicle groups, defined by weight rating rather than by what the truck looks like. Class A is a combination over 26,001 lb GCWR towing more than 10,000 lb; Class B is a single heavy vehicle; Class C is everything else that carries 16+ passengers or placarded hazmat.

Low-poly render of a truck in a training yard with cones
The class is decided by the rating plate, not by the shape of the truck.

The three classes

ClassWhat it coversThe thresholdSection
ACombination vehicleGCWR 26,001+ lb, towing over 10,000 lb§383.91(a)(1)
BHeavy straight vehicleGVWR 26,001+ lb, towing up to 10,000 lb§383.91(a)(2)
CSmall vehicle16+ passengers including the driver, or placarded hazmat§383.91(a)(3)

To run a specific truck and trailer through those thresholds, use the CDL class finder; to weigh the two heavy licences against each other for the work you want, read Class A vs Class B.

Class A licenses down: an A holder may drive B and C vehicles, subject to holding the right endorsements. The reverse is not true, and the common mistake is a B holder hooking a heavy trailer "just this once" — the rating on the trailer plate decides the class, whatever the load weighs on the day.

Low-poly render of a rigid straight truck with a box body parked beside a tractor-trailer, both facing the same way on an empty concrete lot
Left, the rigid straight truck a Class B covers. Right, the tractor and separate trailer that need a Class A.

Endorsements and restrictions

Endorsements add authority; restrictions remove it. The endorsements are H for hazardous materials, N for tank vehicles, X for the two combined, P for passengers, S for school buses and T for double and triple trailers. H and X require a federal security threat assessment, which takes weeks and is the single longest lead time in the whole licensing process.

Restrictions arrive quietly. Take the skills test in a truck with an automatic and you hold an E restriction: no manual transmission. Test without air brakes and you hold L. Test a Class A combination joined by a pintle hook rather than a fifth wheel and you hold O: no fifth-wheel tractor-trailer. Each of them is removable, and each requires re-testing in a vehicle without the limitation.

Getting the licence

  1. 01Complete entry-level driver training with a provider on the federal training registry, before the skills test.
  2. 02Pass the knowledge tests and hold the commercial learner's permit for at least 14 days.
  3. 03Hold a valid medical certificate — the 24-month one from the DOT physical — and self-certify your operating category with the state.
  4. 04Pass the three-part skills test: vehicle inspection, basic control, and the road test.

The training requirement is federal and the registry is federal, but the testing is the state's. A training certificate from an unregistered school is worth nothing at the counter, so check the registry before you pay tuition.

Low-poly render of a truck in a training yard with cones
The yard is where two of the three skills tests happen.

Where the states differ

Part 383 is a floor. States must meet it and may go beyond it, and they do — on minimum age for intrastate work, on the road test route and scoring, on how long a permit lasts, on the fee, and on how fast the medical certification reaches the record. Two neighbouring states can differ by weeks in total elapsed time for exactly the same driver.

Interstate driving is federally 21 and over. Several states license at 18 for intrastate work only, and a driver who takes an interstate load on an intrastate licence has a violation that the carrier shares. Check the state's own commercial licensing page for the current fee and route detail — those are the two things that move most often.

Sources

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