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Find answers to some of the common questions about CDLs below. 

What is a CDL?

A CDL, or Commercial Driver’s license, is a type of driver’s license that allows you to drive a commercial motor vehicle (CMV).

When did CDLs start?

CDLs became a requirement in 1992 with the Commercial Motor Vehicle Safety Act.

This act created federal CDL qualifications and criteria with the aim of improving safety on U.S. roads and highways. 

The act created federal guidelines that all states must meet when issuing commercial driver’s licenses. 

The Federal Motor Carrier Safety Administration (FMCSA) of the Department of Transportation is the agency responsible for developing the standards and procedures for CDL testing and regulations. 

How much does a CDL license cost?

The exact cost of your commercial driver’s license and any endorsements will vary by state.

CDL endorsement costs anywhere from $10 to $100 to add to your license. 

The cost of CDL training school ranges anywhere from $1,000 to $8,000. 

How old do you have to be to have a commercial driver’s license?

Depending on the state, you must be 18 to 21 years old to qualify for a commercial driver’s license. 

Most states have an age limit of 21 years old to drive interstate routes (across state lines) and an 18-year-old age limit to drive within the state that issued your CDL (intrastate).

The CDL age requirements vary slightly from state to state, but are regulated at a federal level. 

What are the different CDL classes?

The different CDL classes are:

  • Class A: Allows you to operate most commercial vehicles with a GVWR of 26,001 pounds or more and a towing weight of 10,000 pounds or more.
  • Class B: Allows you to operate single or combined commercial vehicles with a GVWR of 26,001 pounds when the towing weight is under 10,000 pounds.
  • Class C: Allows you to operate a vehicle designed to carry 16 people (including the driver) under 26,001 pounds or carry hazardous materials under 26,001 pounds. Class C CDL requires either a Passenger or HazMat endorsement.

What are the CDL Restriction Codes?

CDL restriction codes may be added to your license depending on any medical conditions or what kind of vehicle you passed your test in.


Common CDL restriction codes include:

Restriction CodeDetails
BCorrective Lenses
CMechanical Aid
DProsthetic Aid
EAutomatic Transmission Only
FDuel Outside Mirror
GDaylight Only Operation
JSchool/Activity Bus Only
KCDL Intrastate Only
LNo Air Brake CMV
MGroup B or Group C Passenger Vehicles
NGroup C Passenger Vehicles Only
QBus Only
THazmat Prohibited
UHearing Aide Required
VMedical Variance Required
WMedical Waiver Required
XNo Cargo in CMV Tank Vehicle
ZNo Full Air Brake Equipped CMV

Read more about the different CDL classes and endorsements. 

Can you get financial aid for CDL training?

Yes, prospective CDL drivers can apply for financial aid to attend truck driving school. 

Financial aid options for CDL training include:

  • Private student loans.
  • Workforce Investment Act loans.
  • Military Aid.
  • Scholarships or grants.
  • Tuition Reimbursement programs.
  • Company-sponsored CDL training. 

How long is truck driving school?

The length of your CDL training program will vary depending on which Class of CDL you are training for and where you complete the program.

On average, your CDL training will last about 3 months.

However, some truck driving schools can be completed in a few weeks. 

Learn more about truck driving school.

How do you get a CDL without going to school?

If you are going to get a job as a trucker, most companies will require you to have completed some sort of training program. 

The best way to get your CDL without school is through the military. 

What are some CDL license jobs?

Your career options with a commercial driver’s license include more than just hauling cargo from point A to point B. 

Even within the traditional trucking category of transporting goods, you’ve got a nearly endless list of different industries to choose from – all the way from Agriculture and Aerospace to Entertainment and Defense. 

Other CDL and CDL-related jobs include:

  • CDL training instructor.
  • Terminal manager.
  • Fleet manager.
  • Transportation manager.
  • Dispatcher.
  • Bus driver.
  • Deliver driver.
  • Diesel mechanic, truck mechanic.
  • Chauffeur.
  • Yard Switch Operator.
  • CDL Owner-Operator. 

Do truck drivers get fired for accidents?

Yes, in cases where the driver is a fault for a preventable accident, they will typically be fired. 

Some companies may have a 3-strikes or point system depending on the severity or nature of the accident. 

Learn more about truck accident statistics. 

What is autonomous trucking?

Autonomous trucking describes self-driving trucks. 

Autonomous trucking is continuing to advance and become more prevalent in the transportation industry. 

This is for a few reasons:

  1. The self-driving technology is improving quickly.
  2. There is a shortage of qualified truck drivers. 
  3. It can help cut down on truck driving accidents. 

Do self-driving trucks mean you shouldn’t get a CDL if you were thinking about a commercial driving career?

No, fully autonomous trucking and a majority of self-driving trucks on the road is still a long ways off. There is going to need to be a lot of regulation, testing, and infrastructure in place before that happens. 

And, autonomous trucks will still need trained, qualified operators at the controls. CDL will likely be a major requirement for that for quite some time.