Commercial Driver’s License (CDL) classes and endorsements

Learn about the different kinds of commercial driver’s licenses (CDL), as well as which tests and endorsements you’ll need for each.

Overview

Applicants may apply for a CDL beginning at age 18. However, Federal Regulations state that a license holder, including CDL holders, must be 21 years of age to drive a commercial motor vehicle in interstate commerce. Therefore, CDL holders in Massachusetts under the age of 21 will be issued a K restriction (Intrastate Operation Only).

Commercial vehicles are divided into 3 classes based on size, weight, and functionality. Each class requires a different CDL. In addition to classes, you may also get endorsements, which permit you to drive specifically kinds of vehicles. For example, you'll need a special endorsement to drive a school bus. 

CDL Class	Tests Required	Possible Endorsements and Required Tests
Class A (Combination vehicle endorsement required)	General Knowledge Written Exam Combination Endorsement Written Exam Road Exam	H - Hazardous Materials Written Exam N - Tank Vehicles Written Exam P - Passenger Transport Written and Road Exam T - Doubles/Triples Written Exam X - HazMat and Tank Vehicles Written Exam L - Air Brakes Written and Road Exam S - School Bus Written and Road Exam
Class B	General Knowledge Written Exam Road Exam	H - Hazardous Materials Written Exam N - Tank Vehicles Written Exam P - Passenger Transport Written and Road Exam X - HazMat and Tank Vehicles Written Exam L - Air Brakes Written and Road Exam S - School Bus Written and Road Exam
Class C (Passenger, HAZMAT, or Airbrakes endorsement required)	General Knowledge Written Exam Road Exam Note: If upgrading to a Class C from a Class D, no road test is required UNLESS the endorsement requires one.	H - Hazardous Materials Written Exam N - Tank Vehicles Written Exam P - Passenger Transport Written and Road Exam X - HazMat and Tank Vehicles Written Exam L - Air Brakes Written and Road Exam S - School Bus Written and Road Exam

Endorsements

An endorsement is a designation on your CDL that indicates that you're qualified to operate specific kinds of vehicles or to use them in specific ways. For example, you need an endorsement to carry passengers in a commercial vehicle, and you also need an endorsement to drive a vehicle carrying hazardous materials. 

Once you've earned an endorsement, the letter that represents it will be printed on the front of your CDL, and a description on the back. 

Endorsement	Displays on Driver's License as	Description	Testing Requirements
A Endorsement (L restriction Removal)	Does not print on driver's license	Allows the customer to operate a commercial motor vehicles with airbrakes. The A Endorsement is implied in the absence of an L Restriction	Written exam and road test
P Endorsement	Passenger	Allows the customer to carry passengers	Written exam and road test
H Endorsement	Hazardous Materials	Allows the customer to carry hazardous materials or waste	Written exam and Transportation Security Administration threat assessment*
N Endorsement	Tank	Allows the customer to haul liquids in bulk	Written exam
X Endorsement	Tank/Hazmat	This is a combination of the N Endorsement and the H Endorsement. If a customer has both, his/her Commercial Driver's License will display the X Endorsement.	N/A
T Endorsement	Doubles/Triples	Allows the customer to pull double or triple trailers. This endorsement is only available for Class A driver's licenses. However, it is not a requirement for getting a Class A driver's license	Written Exam
S Endorsement	School Bus	Allows the customer to transport students in a full-sized school bus	Written exam and road test

*There are 2 requirements you must meet before getting or renewing a Hazardous Materials Endorsement:

• Apply for and successfully pass the Transportation Security Administration's Security Background Check. This is now required for all Hazardous Materials Endorsement applicants. It could take 60 days or more to receive the results.
• Take and pass the Hazardous Materials Endorsement exam. You can do this at the same time you as getting or renewing your CDL

Call [phone] or visit TSA Enrollment to begin the process.

Self Certification

If you're a CDL driver, you're federally required to self-certify. This means that you must tell the RMV if  you will operate only in Massachusetts, or will cross state lines. You must also tell us if you're required to hold a medical certificate. 

As a Commercial Learners Permit (CLP) or Commercial Driver’s License (CDL) holder, you are federally required to inform the Registry of Motor Vehicles (RMV) of the type of commerce in which you operate (interstate or intrastate), and whether or not you are required to be medically certified. This self-certification is required upon initial issuance, renewal, upgrade, and transfer per federal regulation 49 CFR 383.71. 

You will be required to select a self-certification category on the CLP/CDL Application. If you fall into a non-excepted category, the RMV must verify that you are medically qualified to operate a Commercial Motor Vehicle (CMV).  You may also need to provide the RMV with documentation showing that you have a medical or skills performance evaluation variance.