CDL
Commercial Driver's License (CDL)
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ExploreAbout this exam
A Commercial Driver's License (CDL) is a credential that authorizes you to operate a Commercial Motor Vehicle (CMV) on public roads. Driving a CMV demands a higher level of knowledge, experience, skills, and physical ability than driving a non-commercial vehicle, and CDL holders are held to a higher standard whenever they operate any type of motor vehicle on public roads. Serious traffic violations committed by a CDL holder can affect the ability to keep the CDL certification.
CDLs are not issued by the federal government. FMCSA does not issue CDLs; state governments are responsible for issuing them, and most drivers must obtain a CDL through their home State. Holding a license from more than one State is illegal. To obtain a CDL, an applicant must pass both skills and knowledge testing geared to these higher standards. Additional endorsements may be required for drivers of trucks with double or triple trailers, trucks with a tank, trucks carrying hazardous materials, and passenger vehicles.
Preparation means studying your home State's driver licensing materials, then practicing behind the wheel with a qualified CDL holder. Because requirements, fees, and scheduling vary by State, contact your State licensing bureau (for example, the Department of Motor Vehicles) for details on applications, testing, and endorsements.
What you'll study
About CDL preparation
Who actually issues my CDL?
Your home State does. FMCSA does not issue Commercial Driver's Licenses; state governments are responsible for issuing them. Contact your State licensing bureau, such as the Department of Motor Vehicles, for application steps, scheduling, and fees.
What does the testing involve?
An applicant must pass both knowledge testing and skills testing geared to the higher standards required for commercial motor vehicle operation. Plan to prepare for both parts, since passing one does not substitute for the other.
Can I hold a CDL from more than one State?
No. Most drivers must obtain a CDL through their home State, and it is illegal to have a license from more than one State. Apply where you actually reside rather than shopping for a license elsewhere.
When do I need an endorsement on top of the CDL?
Special endorsements may be required if you will drive a truck with double or triple trailers, a truck with a tank, a truck carrying hazardous materials, or a passenger vehicle. Your State licensing bureau can confirm which endorsements apply to the job you want.
How much does the test cost and how long is it?
Those details are set by each State, not by FMCSA, and are not published in the federal overview. Check with your State licensing bureau for current fees, test length, appointment availability, and any preparation materials it provides.
What happens if I fail a knowledge or skills test?
Retake rules, waiting periods, and any additional fees are State-specific and are not stated in the federal overview. Ask your State licensing bureau what its retake policy is before you schedule, so you can budget time and money accordingly.
What is the most common mistake candidates make?
Underestimating the higher standard that applies after licensing. CDL holders are held to a higher standard when operating any type of motor vehicle, and serious traffic violations can affect the ability to maintain CDL certification, so safe habits matter beyond the test day.
In what order should I study?
Start with general CMV knowledge, then add the specific areas tied to what you will drive, such as tank, hazardous materials, double or triple trailers, or passenger vehicles, since those require endorsements. Confirm the exact test structure with your State licensing bureau before booking.
Where can I get official information?
Use FMCSA's Commercial Driver's License Program pages for the federal overview and links to State resources, and use your State licensing bureau for anything transactional, including applications, appointments, fees, and endorsements.