Commercial Driver’s License Endorsements

Professional truck drivers keep America moving—delivering the goods, equipment, and materials that fuel businesses, supply restaurants, and support industries across the nation. While most freight can be handled by any driver with a Commercial Driver’s License (CDL), certain types of loads require specialized training and certification. That’s where Commercial Driver’s License endorsements come into the picture.

A CDL endorsement is an added qualification on your license that authorizes you to operate specific vehicles or transport unique types of cargo. These include hauling hazardous materials, driving passenger vehicles like buses, or towing multiple trailers. Getting one or more endorsements isn’t only an enhancement to your driving skills but a competitive advantage; which often leads to higher pay plus better and broader career opportunities.

Whether you’re just starting your trucking career or looking to expand your expertise, understanding CDL endorsements is essential to learn about how your long-term trucking career can look like. In this guide, we’ll explore what CDL endorsements are, the different types available, and how to get them, so you can reach your best in your commercial driving career.

What is a CDL endorsement?

A CDL endorsement is an additional certification added to a Commercial Driver’s License (CDL) that allows you to operate specialized types of vehicles or transport certain kinds of freight. Depending on the type of CDL license—A, B, or C—you can earn specific endorsements that expand the scope of what you’re legally permitted to drive.

These endorsements are not automatically included with a CDL; instead, you must complete extra training and pass specific skills tests to qualify. By getting one or more endorsements, you can legally qualify to handle tasks such as transporting hazardous materials, operating passenger vehicles like buses, or towing multi-trailer combinations.

Each endorsement is represented by a code that is printed on your commercial driver’s license. On the license, these codes appear on the front side, under the “Expiration Date” field following the letter “E”. For a full description of each endorsement you hold, you can refer to the back of your license, which provides details about the additional driving privileges associated with each code.

Types of CDL endorsements

While the exact requirements can vary from state to state, there are generally six primary CDL endorsements that drivers can add to their Commercial Driver’s License. Each endorsement allows you to operate specific types of commercial motor vehicles (CMVs) or transport certain types of cargo that require specialized knowledge and skills.

To earn these endorsements, you’ll need to undergo additional training and pass specific written and/or skills tests beyond the standard CDL exam. When applying for your CDL, you can select which endorsements you wish to pursue, and the testing center will provide the corresponding exams for each one. Just like CDL classifications (Class A, B, or C) differ slightly across states, endorsement requirements also vary, so it’s important to check your state’s specific guidelines before applying. 

The six common CDL endorsements include the following:

H – Hazardous Materials (HAZMAT) endorsement

The Hazardous Materials (H) endorsement, commonly known as the HazMat endorsement, is required to transport hazardous or potentially dangerous materials such as gases, oils, chemicals, and even certain household products. This endorsement can be added to Class A, B, or C type CDLs.

Due to the high risk associated with hauling hazardous cargo, getting a HazMat endorsement involves additional steps. Drivers must pass a written knowledge test covering safe handling procedures and federal regulations and complete a Transportation Security Administration (TSA) security threat assessment. In addition, a DOT medical examination may also be required. The TSA background check can take 60 days or more, and the written exam can be completed alongside your CDL application or renewal. Meeting these requirements is necessary to legally transport hazardous materials and comply with federal regulations.

Holding a HazMat endorsement opens doors to higher-paying jobs and a broader range of opportunities. It also serves as a prerequisite for the X endorsement, which combines both Tank Vehicle (N) and HazMat (H) qualifications. Overall, the H endorsement certifies that you have the training, skills, and federal clearance to safely transport hazardous materials.

N – Tank Vehicle endorsement  

The N (Tank Vehicle) endorsement is required to operate tanker trucks carrying liquids or gases. This endorsement focuses on safe loading, unloading, and handling of tank cargo, as well as maintaining vehicle stability during transit. Many trucking companies require applicants to already hold this endorsement when applying for tanker positions.

To earn the N endorsement, drivers must pass a written knowledge test covering the unique challenges of transporting liquid or gaseous cargo. Unlike solid freight, liquids can shift within the tank, affecting weight distribution and handling. Training focuses on managing this “liquid surge”, ensuring vehicle stability, and safely maneuvering the tanker.

The Tank Vehicle endorsement can be added to Class A and Class B type CDLs. Drivers with this credential gain access to specialized tanker jobs, which often offer higher pay and local or regional routes with more consistent home time. Overall, the N endorsement equips drivers with the skills and qualifications necessary to safely transport liquids and gases while advancing their commercial driving careers.

X – Tanker/HazMat combination endorsement

The X (Tanker/HazMat combination) endorsement is a combination of the Tank Vehicle (N) and Hazardous Materials (H) endorsements. It allows transport of hazardous materials in tanker vehicles and is available for Class A and B CDL holders. The combination endorsement is especially valuable in industries that handle fuel, chemicals, or other liquid or gaseous hazardous cargo.

While holding the X endorsement doesn’t limit your hauling ability to transport hazardous materials, it provides the legal qualification, permission, and flexibility to do so whenever needed. To obtain the X endorsement, drivers must pass a written knowledge test and already meet the requirements for both the Tank and HazMat endorsements.

The X endorsement demonstrates advanced skills and specialized training, setting drivers apart in the gas, oil, and chemical transportation sectors. It often opens doors to higher-paying opportunities and a wider range of trucking assignments.

T – Double/Triple trailers endorsement

The T endorsement, commonly known as the Doubles/Triples endorsement, allows drivers to operate trucks pulling two or three trailers simultaneously, significantly increasing cargo capacity. This endorsement is only available for Class A CDL holders and requires a written knowledge test to demonstrate understanding of the unique challenges.

Driving double or triple trailers requires advanced skills and carries additional risks. The extended length and extra weight make these combinations more prone to tipping or rollover, demanding careful maneuvering, braking, and constant awareness on the road.

Holding a T endorsement enhances a driver’s skill set and opens the door to higher-paying positions, as employers value drivers who can safely manage these larger, more complex vehicle combinations. If you are looking to maximize cargo loads efficiently, the T endorsement is a highly valuable addition to a Class A CDL.

Note: Some states restrict or prohibit the operation of double or triple trailers, so always check local regulations before applying for the T endorsement.

P – Passenger endorsement

The Passenger (P) endorsement allows you to operate vehicles designed to carry 16 or more passengers, including the driver. This endorsement can be added to Class A, B, or C CDLs and is essential for those who want to drive buses, large vans, or other passenger vehicles.

To obtain the P endorsement, you must pass a written knowledge test and a road skills test that evaluates your ability to safely transport passengers in compliance with federal and state regulations. You must also meet additional requirements for driving a school bus, including separate forms and a federal background check, as the S (School Bus) endorsement is required in addition to the P endorsement.

This endorsement is valuable for careers in passenger transport, such as city commuter buses, long-distance coaches, or charter services. These roles often offer structured schedules and regular home time, though drivers should be prepared for frequent interaction with passengers. Holding the P endorsement is also a prerequisite for obtaining the S endorsement, making it an important step for those pursuing careers in school transportation.

S – School bus endorsement

The School Bus (S) endorsement is required for drivers with Class A, B, or C CDLs to operate school buses and transport students. To qualify, drivers must first hold a Passenger (P) endorsement, which permits them to carry passengers in general. The application process includes a written knowledge test, a road skills test, a background check, and a physical fitness assessment. Drivers also receive specialized training on student safety, loading and unloading procedures, and compliance with school zone regulations. 

In addition to technical skills, school bus drivers must demonstrate patience, alertness, and the ability to manage children while driving. Ongoing supplemental training helps drivers stay current with changing safety rules. Holding both the P and S endorsements ensures drivers meet all federal and state requirements for safely transporting students.

State-specific CDL endorsements

In addition to the standard federal CDL endorsements, individual states have the authority to establish their own unique endorsements. Some states utilize this flexibility to create specialized endorsements, while others stick to the basic set. Examples include:

Farm vehicle endorsements: 

Many states offer endorsements specifically for operating farm vehicles. For instance, in New York, the F and G endorsements can be added to Class A and Class B CDLs. In Michigan, a farm endorsement is available for Class B or Class C CDLs, though holders of a Class A license are typically exempt from this requirement.

Recreational vehicle endorsements: 

Certain states require special endorsements for operating larger recreational vehicles. For example, Class C CDL holders in California must obtain a fifth-wheel recreational trailer endorsement for rigs weighing between 10,001 and 15,000 pounds.

Air brake endorsements: 

Some states require a separate air brake endorsement for drivers operating commercial vehicles equipped with air brakes. While most states address this under license restrictions, others, such as New Hampshire, have a designated air brake endorsement.

The A Endorsement (Air Brake – L Restriction removal) allows you to operate commercial vehicles with air brakes. This endorsement is generally assumed if the L restriction on the CDL is removed, meaning no separate notation appears on the license itself.

To obtain this endorsement, you must complete both a written knowledge test and a road skills test that demonstrates safe handling of air brake-equipped vehicles. Because air brake requirements vary by state, it is important to check your local DMV regulations before applying or upgrading your CDL to ensure full compliance with state-specific rules.

CDL endorsements by license class

CDL endorsements provide drivers with the qualifications needed to operate specific types of vehicles, transport hazardous materials, or carry passengers such as school children. The availability of endorsements varies depending on the CDL class you hold.

CDL Class	Required Tests	Endorsement	Tests Required for Endorsement
Class A CDL (Combination vehicle endorsement required)	General Knowledge Written Exam, Combination Vehicle Written Exam, Road Skills 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 & Tank Combination	Written Exam
		L – Air Brakes	Written and Road Exam
		S – School Bus	Written and Road Exam
Class B CDL	General Knowledge Written Exam, Road Skills Exam	H – Hazardous Materials	Written Exam
		N – Tank Vehicles	Written Exam
		P – Passenger Transport	Written and Road Exam
		X – HazMat & Tank Combination	Written Exam
		L – Air Brakes	Written and Road Exam
		S – School Bus	Written and Road Exam
Class C CDL (Passenger, HAZMAT, or Airbrakes endorsement required)	General Knowledge Written Exam, Road Skills Exam*	H – Hazardous Materials	Written Exam
		N – Tank Vehicles	Written Exam
		P – Passenger Transport	Written and Road Exam
		X – HazMat & Tank Combination	Written Exam
		L – Air Brakes	Written and Road Exam
		S – School Bus	Written and Road Exam

These endorsements ensure that drivers are properly trained and legally authorized to operate specialized commercial vehicles and handle specific types of cargo or passengers.

How to get a CDL endorsement?

Obtaining a CDL endorsement requires a combination of knowledge, training, and testing, depending on the type of endorsement you seek. Endorsements expand your qualifications and allow you to operate specialized vehicles or haul specific types of cargo. Here’s a step-by-step guide:

Step 1: Meet the eligibility requirements

Before applying for any endorsement, ensure you meet the basic requirements:

• Be at least 18 years old for intrastate driving.
• Be at least 21 years old for endorsements like HazMat (H), School Bus (S), or Passenger (P).
• Hold a valid driver’s license or commercial driver’s license (CDL).

 

Step 2: Prepare for the endorsement exams

Each endorsement requires a written knowledge test that evaluates your understanding of safety regulations, cargo handling, and vehicle-specific operations. For endorsements such as Passenger (P) or School Bus (S), you will also need to complete a road skills test to demonstrate your ability to operate the vehicle safely.

Many driving schools offer study guides, practice tests, and training programs to help you prepare for these exams. Thorough preparation is crucial, as the written tests cover both general safety and the unique requirements of each endorsement.

Step 3: Take the written knowledge test

Schedule your written exam at your local DMV. Tests are typically taken in person, either on the same day as your CDL permit test or separately. Some states offer the knowledge test in multiple languages, such as Spanish, but availability varies.

Step 4: Complete additional requirements (if applicable)

Certain endorsements have extra requirements:

• HazMat (H) or School Bus (S): You must undergo a background check to verify your trustworthiness to handle hazardous materials or transport children.
• Passenger (P) or School Bus (S): You will need to complete a road skills test in the specific vehicle type, such as a bus, to demonstrate competency.

 

Step 5: Receive your endorsement

Once you pass the necessary exams and meet all requirements, the endorsement will be added to your CDL, officially qualifying you to operate the specialized vehicle or transport the designated cargo.

Note: Requirements and procedures can vary by state, so always check with your local DMV to confirm the process for adding endorsements to your CDL.

Maximize your potential with CDL endorsements

CDL endorsements are more than just additional qualifications—they are career boosters that open doors to higher-paying positions and a wider range of opportunities across the transportation industry. Whether your goal is to transport hazardous materials, operate tankers, or drive school buses, earning the right endorsements ensures you are fully trained, compliant with safety regulations, and prepared to handle specialized tasks.

By understanding and getting the endorsements that align with your career goals, you not only enhance your skills and versatility but also position yourself as a more competitive, advanced, and valuable driver. Investing in the proper certifications and endorsements is more than meeting legal requirements. With the combination, your trucking career can reach its highest potential once you progress through the years. 

Frequently asked questions about CDL endorsements

Why are CDL endorsements important?

CDL endorsements play a crucial role in advancing your trucking career. They not only expand your skill set but also make you a more appealing candidate to employers. Companies often seek drivers with specialized endorsements because they demonstrate expertise in handling specific vehicles or types of cargo. 

For example, a HazMat endorsement signals that a driver is qualified to transport hazardous materials safely—a responsibility that often comes with higher-paying job opportunities.

Obtaining CDL endorsements isn’t just an extra credential—it can significantly elevate your career:

• Higher earnings: Drivers with endorsements are in greater demand, which can result in 10–30% higher pay compared to drivers without them.
• Broader job opportunities: Endorsements make you more versatile, opening the door to a wider range of trucking positions, from passenger transport to tankers and hazardous materials.
• Improved driving skills: Each endorsement requires additional training and testing, making you a more skilled, responsible, and safer driver on the road.

 

What is the difference between CDL endorsements and restrictions?

CDL endorsements and restrictions serve opposite purposes on a commercial driver’s license. While endorsements expand your driving privileges, allowing you to operate additional types of vehicles or haul specialized cargo, CDL restrictions limit your driving privileges based on skills, vehicle type, or medical conditions.

CDL restrictions are typically applied after completing the knowledge and skills tests. They can result from failing specific portions of the test or taking your road test in a vehicle that doesn’t meet certain criteria. For example, if you complete your Class A road test in a truck without a fifth-wheel connection, you’ll receive the O restriction, which prevents you from driving fifth-wheel Class A setups.

To minimize restrictions, it’s important to take your CDL test in the type of vehicle you plan to operate professionally. This is especially critical for vehicles like school buses or trucks equipped with air brakes.

Common CDL restrictions include:

• E: No manual transmission vehicles
• L & Z: No vehicles equipped with full air brakes
• V: Medical variance applied
• M: Limited to driving school buses and passenger vehicles that are Class B or C
• N: Passenger vehicles or school buses must be Class C only
• K: Restricted to intrastate travel

 

Can you have more than one CDL endorsement?

Yes, a driver can hold multiple CDL endorsements, and the endorsements you are eligible for depend on your CDL class. You don’t have to add them all at once—you can obtain endorsements when you first get your CDL or add them later as needed.

How to get multiple endorsements:

1. Take written exams: Many drivers choose to take written tests for multiple endorsements during a single DMV visit to streamline the process. 
2. Meet additional requirements: Some endorsements require extra steps beyond the written test. For instance, the HazMat (H) endorsement requires a federal background check, fingerprinting, and a TSA security threat assessment.
3. Add endorsements later: You can apply for new endorsements after receiving your CDL, allowing you to expand your driving privileges as your needs or opportunities grow.

How long does a CDL endorsement last?

Most CDL endorsements remain valid for the same duration as your Commercial Driver’s License (CDL). However, certain endorsements have specific renewal requirements:

• Hazardous Materials (H) Endorsement: This endorsement must be renewed every five years. Renewal includes a new background check and fingerprinting as mandated by the TSA. It’s recommended to start the renewal process at least 60 days before expiration to prevent a lapse in certification.
• Other Endorsements (P, S, T, N, X, etc.): Generally, these endorsements expire alongside your CDL. Some may require a written knowledge test or road skills test upon renewal, depending on state regulations.

 

Do CDL endorsements expire?

Yes, CDL endorsements can expire, and the renewal process depends on the type of endorsement. Most endorsements generally expire alongside your Commercial Driver’s License, and in some cases, you may need to retake the corresponding knowledge or skills test to renew them.

Certain endorsements, such as the Hazardous Materials (H) or the Tanker/HazMat combination (X), have additional requirements. For example, the HazMat endorsement requires a separate background check and renewal every five years, regardless of your CDL’s expiration date. Keeping your endorsements up to date ensures you remain fully qualified and compliant to operate specialized vehicles or transport specific types of cargo.

How much does it cost to get a CDL endorsement?

The cost of obtaining a CDL endorsement can vary depending on your state and the type of endorsement. Generally, expenses include a small DMV fee for the written test and license update, as well as additional charges for requirements such as background checks or specialized training.

Typical CDL endorsement cost includes:

• State DMV fees: Most states charge a fee ranging from a few dollars up to around $20 for taking the written test, updating your license, and processing the endorsement.
• Background checks: Endorsements like HazMat (H) require a federal background check and fingerprinting, which typically costs about $83. Some states may provide discounts if you hold a valid Transportation Worker Identification Credential (TWIC).
• Training costs: Certain endorsements, such as passenger or tanker endorsements, may require specific training courses, which can add to your overall expenses.
• Testing fees: Some states charge separate fees for endorsement tests in addition to the standard DMV endorsement fee.