CDL license classes and requirements: Class A, B, C, endorsements and how to get a CDL

Checked against official sources · Last reviewed October 6, 2026

A CDL license (commercial driver's license) is issued by your home state under federal rules and lets you drive a class of commercial motor vehicle. There are three classes: A for combination vehicles, B for heavy straight vehicles and C for small vehicles designed to carry 16 or more passengers or that haul placarded hazardous materials.

Endorsements add vehicle types such as tankers, hazmat, double/triple trailers and buses. You get your first CDL license by holding a commercial learner's permit, finishing entry-level driver training for Class A or B, and passing a skills test. [1][3][4][5][6][7]

CDL classes: Class A, B and C

The license shows which vehicle groups you may drive: A for combination vehicle, B for heavy straight vehicle and C for small vehicle. The weight tests use the weight rating or the actual weight, whichever is greater.

The examples below only show how the tests apply. Check your own vehicle's ratings and loaded weight.

Sources: [1][2][3][5][16]

Do you need a CDL?

Under federal rules you need a CDL when your vehicle falls into one of the three groups:

• A combination with a combined rating or weight of 26,001 lbs or more, when the trailer's rating or weight is over 10,000 lbs (Class A).
• A single vehicle with a rating or weight of 26,001 lbs or more, even if it tows a trailer rated 10,000 lbs or less (Class B).
• A vehicle of any size hauling placarded hazardous materials (or any quantity of a listed select agent or toxin), or one designed to carry 16 or more passengers including the driver (Class C).

A non-hazmat freight truck that stays under the Class A and B lines doesn't need a CDL under federal rules. The CDL rules apply whether you drive across state lines or only inside one state.

For a combination, the combined rating (GCWR) is the greater of the value on the truck's FMVSS certification label, if shown, or the highest sum of the truck's and trailer's ratings or weights. [1][2][3][17][18]

Class A vs Class B CDL: what's the difference?

Class A is for combinations: a combined weight rating or actual weight of 26,001 lbs or more, where the towed unit's rating or weight is over 10,000 lbs. Class B is for a single heavy vehicle: a rating or actual weight of 26,001 lbs or more, including one towing a trailer rated 10,000 lbs or less. Both tests use the weight rating or the actual weight, whichever is greater.

A driver who passed the Class A knowledge and skills tests may also drive Class B and Class C vehicles, and one who passed the Class B tests may drive Class C vehicles, as long as they hold any endorsements those vehicles need. To drive in a group your CDL doesn't cover, you retake and pass the related tests. An upgrade from B to A needs a learner's permit first and entry-level driver training.

If you take the Class A skills test in a combination connected by a pintle hook or other non-fifth-wheel hitch, your license gets an O restriction: no tractor-trailer combination connected by a fifth wheel that requires a Class A CDL.

Sources: [1][2][4][6][16][19]

CDL endorsements

You need an endorsement on your CDL to drive double/triple trailers, passenger vehicles, tank vehicles, school buses, or vehicles hauling hazardous materials. Each endorsement takes its own test on top of the CDL's knowledge and skills tests.

A tank vehicle (tanker) is a commercial motor vehicle designed to carry liquids or gases in a tank or tanks with an individual rated capacity over 119 gallons and a total rated capacity of 1,000 gallons or more, whether the tank is attached permanently or temporarily. An empty storage tank not designed for transportation, temporarily attached to a flatbed trailer, doesn't count.

For the hazmat endorsement, the state can't issue, renew, upgrade or transfer it unless the TSA (Transportation Security Administration) has found you don't pose a security risk, or you hold a valid TWIC (Transportation Worker Identification Credential). States must make you renew it at least every 5 years, so the TSA screening repeats.

More on the hazmat endorsement: requirements, TSA check and cost.

Sources: [3][4][5][6][7][20]

Commercial learner's permit (CDL permit)

A commercial learner's permit (CLP) is required before your first CDL, and before an upgrade that needs a skills test. To get one you must:

• Be 18 or older, with proof of age.
• Pass a general knowledge test for the vehicle group you'll drive (and, if you want a P, S or N endorsement, that endorsement's knowledge test).
• Certify that you aren't disqualified and don't hold a license from more than one state.
• Show proof of citizenship or lawful permanent residency (or get a non-domiciled CLP), proof that the state is your state of domicile, and the states where you've been licensed in the past 10 years.

With a CLP you may drive on public roads for training only with a valid CDL holder of the right class and endorsements beside you in the front seat (in a passenger vehicle, directly behind you or in the first row behind you), watching and directly supervising. You must also hold a valid driver's license from the same state. You can't haul hazardous materials on a CLP, and the only endorsements allowed on it are P, S and N.

A CLP is valid for at most one year from its first issue date without retaking the knowledge tests. You can't take the CDL skills test in the first 14 days after the CLP is first issued.

More on the CDL permit and permit test. [4][6][7]

Entry-level driver training (ELDT)

If you got your CLP on or after February 7, 2022, you must finish entry-level driver training from a provider on FMCSA's Training Provider Registry before taking the skills test for a Class A or B CDL, or for a P or S endorsement, for the first time. For a first hazmat (H) endorsement, the training comes before the hazmat knowledge test.

ELDT covers first-time Class A and B CDLs and upgrades to them. Except for the hazmat endorsement, the theory and behind-the-wheel parts must be done within one year of finishing the first part. Once you complete the course, the training provider submits your certification to FMCSA (Federal Motor Carrier Safety Administration) through the registry.

More on CDL training (ELDT) and how to check a school is registered. [7][19][21][22]

How long does it take to get a CDL, and what does it cost?

The federal rules set two timing checkpoints, not a total time. You can't take the skills test in the first 14 days after your learner's permit is first issued, and for a first Class A or B CDL you must finish entry-level driver training before the skills test. The permit is valid for at most one year from its first issue date without retaking the knowledge tests, and (except for hazmat) the training's theory and behind-the-wheel parts must be done within one year of finishing the first part.

We haven't found an official national figure for what a CDL costs. Your state issues the permit and the license, and entry-level training comes from a provider you pick from FMCSA's Training Provider Registry, so the cost depends on your state and your training provider. [3][4][7][19][21]

Restrictions on your CDL

The vehicle you test in can limit what you may drive. The state adds a restriction code to your license in these cases:

Sources: [5][16]

How old do you have to be?

You must be 18 or older to get a commercial learner's permit, and a permit comes before your first CDL.

To drive a commercial motor vehicle in interstate commerce under the federal driver qualification rules, you must be at least 21, unless an exception applies. A driver who operates only within one state is subject to that state's driver qualification requirements. [4][7][8][23]

CDL self-certification: the four categories

When you apply for a CDL, you make one of four certifications about the kind of driving you do. Interstate means you drive or expect to drive in interstate commerce; intrastate means only within your state. Excepted means you only do kinds of driving that are excepted from all or part of the driver qualification rules.

Sources: [7]

Medical card, drug testing and the Clearinghouse

The CDL rule's medical certification documentation requirements apply to applicants and CLP or CDL holders who self-certify non-excepted interstate (see the four categories above). Since June 23, 2025, a new CLP or CDL applicant who will drive in non-excepted interstate commerce must be examined and certified by a medical examiner. FMCSA sends the certificate to the state electronically. You must be re-certified at least every 24 months (more often for some drivers), and CDL and CLP holders with a current certificate no longer have to carry the medical card. See DOT physical.

DOT drug and alcohol testing applies to drivers who need a CDL and to their employers; see DOT drug testing. States must check the Drug and Alcohol Clearinghouse and can't issue, renew, transfer or upgrade a CDL for a driver who is prohibited from driving. [7][24][25][26][27]

Disqualification and the one-license rule

You may hold only one driver's license at a time if you drive a commercial motor vehicle.

A disqualified driver must not drive a CMV, and an employer must not knowingly let one. CLP and CDL holders can be disqualified for listed offenses whether they were driving a CMV or another vehicle. For example, a first conviction for driving a CMV (one not hauling hazardous materials, which has its own column in the rule) under the influence of alcohol, or with an alcohol concentration of 0.04 or greater, means a 1-year disqualification from driving a CMV. [28][29]

Common questions