The Ultimate CDL Guide: Everything Drivers Need to Know
Read time: 8 minutes
Last updated: June 3, 2026
A Commercial Driver’s License (CDL) is a license required to operate certain commercial motor vehicles (CMVs) in the United States. The Federal Motor Carrier Safety Administration (FMCSA) establishes national CDL standards, while individual states issue CDL credentials and administer testing requirements.
Drivers typically need a CDL to operate tractor-trailers, large trucks, buses, and vehicles transporting hazardous materials. Depending on the vehicle type and cargo, drivers may need a Class A, Class B, or Class C CDL, along with additional endorsements.
Whether you’re starting a trucking career, becoming an owner-operator, or building a motor carrier business, understanding CDL requirements is an important first step toward legal and compliant commercial driving.
Key Takeaways
- A Commercial Driver’s License (CDL) is required to operate many commercial motor vehicles in the United States.
- The FMCSA establishes national CDL standards, while states issue licenses and administer testing.
- Most new Class A and Class B CDL applicants must complete Entry-Level Driver Training (ELDT) before taking the CDL skills test.
- CDL licenses are divided into Class A, Class B, and Class C categories based on vehicle type and weight.
- Additional endorsements may be required for hazardous materials, passenger transportation, school buses, tank vehicles, and other specialized operations.
- CDL holders must maintain medical certification and comply with FMCSA safety regulations to keep their driving privileges.
What Is a Commercial Driver’s License?
A CDL gives a driver the legal right to operate commercial motor vehicles (CMVs). These include tractor-trailers, buses, and commercial vehicles that transport hazardous materials.
The Federal Motor Carrier Safety Administration (FMCSA) is the federal agency responsible for regulating commercial motor vehicle safety and establishing national CDL standards.
The Commercial Motor Vehicle Safety Act of 1986 set national standards and required states to issue commercial driver’s licenses that meet federal testing rules. CDL rules are also designed to prevent drivers from holding more than one driver’s license at a time. State licensing agencies may require applicants to surrender another active license when applying for a CLP or CDL.
In short, a CDL is proof that you’re qualified to operate motor vehicles designed for business, including single vehicle operations, vehicles towing heavy loads, or those carrying passengers.
What Are the CDL Eligibility Requirements?
To apply, applicants must meet these licensing and testing requirements:
- Be at least 18 for commercial driving within one state, or 21 to drive in interstate commerce or haul hazardous materials.
- Hold a valid driver’s license with legal presence in the U.S.
- Pass a knowledge test and a written test on federal and state rules.
- Complete a driving test, including skills tests, a road test, and a CDL skills test.
- Obtain medical certification from certified medical examiners listed in the National Registry.
Meeting these requirements ensures that only trained commercial drivers are allowed commercial driving privileges.
How to Get a Commercial Driver’s License
The process varies by state, but here are the main steps:
Step 1: Get a Commercial Learner’s Permit (CLP)
Before taking the CDL skills tests, you’ll need a commercial learner’s permit (CLP). A CLP allows you to practice driving a commercial motor vehicle with a licensed CDL holder next to you.
To qualify, you’ll need:
- To pass the required knowledge tests.
- Provide proof of residency and medical examinations.
- Show that you meet federal motor carrier safety standards.
- Pay fees at your local DMV office.
Your permit will include an expiration date, so plan your training and driving test accordingly.
Step 2: Complete Entry-Level Driver Training (ELDT)
Federal rules require most new CDL Class A and Class B CDL applicants to complete entry-level driver training with a registered training provider. This training provider reports successful completion of your course to the FMCSA’s Training Provider Registry.
Without ELDT, you cannot take the skills test or apply for certain endorsements.
Step 3: Take the CDL Skills Test
After at least 14 days with your CLP and completing training, you can schedule the CDL skills tests. These include:
- Vehicle Inspection Test – Show you can check a commercial motor vehicle for safety.
- Basic Controls Test – Prove you can handle commercial vehicles using both manual transmission and automatic transmission systems.
- Road Test – Drive in traffic to show you can safely operate a commercial vehicle.
Passing the skills test earns you a valid CDL. Some states issue the CDL document the same day, while others mail it later. Always double-check it before leaving the DMV office.
Once you’ve earned your CDL and are ready to start operating commercially, you’ll likely need a USDOT Number before hauling freight. Many interstate carriers also need MC Authority to transport regulated commodities across state lines legally.
What Are the Different Types of CDL Licenses?
CDLs are divided into three main categories based on gross vehicle weight rating (GVWR) and gross combination weight rating (GCWR).
| CDL Class | Typical Vehicle Types | Weight Requirements |
|---|---|---|
| Class A | Tractor-trailers, flatbeds, livestock haulers | GCWR 26,001+ lbs with trailer over 10,000 lbs |
| Class B | Straight trucks, buses, dump trucks | Single vehicle GVWR 26,001+ lbs |
| Class C | Passenger vans, small hazmat vehicles | Vehicles requiring passenger or hazmat endorsements |
Class A CDL
A Class A CDL generally allows drivers to operate combination vehicles with a gross combination weight rating of 26,001 pounds or more when the towed unit exceeds 10,000 pounds. Examples include:
- Tractor trailers
- Flatbeds
- Livestock carriers
- Large truck-trailer combinations
Class B CDL
A Class B CDL is for a single vehicle with a GVWR of 26,001 pounds or more, towing no more than 10,000 pounds. Examples include:
- Box trucks
- Dump trucks with small trailers
- Large passenger buses
- Straight trucks
Class C CDL
A Class C CDL applies to certain vehicles that carry 16 or more people, including the driver, or vehicles used to transport hazardous materials. Examples include:
- School bus operations
- Small hazmat vehicles
- Passenger vans
What CDL Endorsements Are Available?
Endorsements expand your commercial driving privileges. Common ones include:
- Hazardous Materials Endorsement (HME) – Also known as a hazmat endorsement, this requires a hazardous materials knowledge test, background check, and fingerprinting.
- Passenger Vehicle (P) – Needed to operate a bus or other passenger vehicle.
- School Bus (S) – Required to drive a school bus safely.
- Tank Vehicles (N) – For liquid or gas cargo.
- Double/Triple Trailers (T) – For pulling multiple trailers.
- Air Brakes – Needed to operate vehicles with air brake systems.
Some endorsements require both a written test and a skills test. The California DMV and other state offices manage endorsement rules and fees.
Why Do CDL Holders Need Medical Certification?
CDL holders must maintain current medical certification. This includes:
- Regular medical examinations by certified medical examiners.
- Submit medical variance information if applicable.
- Meeting federal regulations set by FMCSA.
What Is the FMCSA Drug and Alcohol Clearinghouse?
The FMCSA’s Drug and Alcohol Clearinghouse is a secure system that tracks CDL holders with drug or alcohol violations. Also called the alcohol clearinghouse, it prevents unsafe commercial drivers from returning to work until they complete the required steps.
Employers must conduct Drug and Alcohol Clearinghouse queries during the hiring process and perform annual checks on CDL drivers. Drivers with unresolved drug or alcohol violations cannot legally perform safety-sensitive functions until they complete the required return-to-duty process.
How Do You Maintain a CDL?
To keep your commercial driving privileges, you must:
- Stay compliant with federal regulations and state laws.
- Renew your license before its expiration date.
- Keep up with the required medical certification.
- Follow rules for motor vehicles in interstate commerce.
Failing to comply can result in penalties, suspension, or loss of your license.
Are There CDL Benefits for Military Personnel and Veterans?
Many states make it easier for veterans to obtain commercial driver’s licenses by recognizing military driving experience. Some waive the skills test if you’ve operated similar commercial motor vehicles while in service.
This support helps service members transition into civilian careers as commercial drivers.
For more information, visit the FMCSA Commercial Driver’s License (CDL) Program page.
A regular driver’s license allows a person to operate standard personal vehicles. A Commercial Driver’s License (CDL) is required to operate certain commercial motor vehicles, including large trucks, buses, and vehicles that transport hazardous materials.
A CDL is generally required for many large commercial vehicles, combination vehicles, buses, passenger vehicles carrying 16 or more people, including the driver, and vehicles transporting hazardous materials. The exact CDL class depends on the vehicle’s weight, design, and use.
The timeline depends on the state, training provider, testing availability, and the type of CDL being requested. Most applicants must first obtain a Commercial Learner’s Permit (CLP), hold it for the required period, complete any required training, and pass the CDL skills test.
Most new Class A and Class B CDL applicants must complete Entry-Level Driver Training (ELDT) through a provider listed in the FMCSA Training Provider Registry before taking the CDL skills test. ELDT may also be required for certain endorsements.
Yes. Some states allow qualified military personnel or veterans to use relevant military driving experience to waive certain CDL skills testing requirements. The driver must still meet state licensing rules, medical certification requirements, and any applicable knowledge testing requirements.
If a CDL medical certificate expires, the driver may lose commercial driving privileges until updated medical certification is submitted and accepted by the state licensing agency. Drivers should renew their medical certification before the expiration date to avoid interruptions.
Starting a Trucking Business After Getting a CDL?
Obtaining a CDL is only one part of launching a trucking business. New carriers may also need a USDOT Number, MC Authority, BOC-3 Filing, and Unified Carrier Registration (UCR). FCCR helps owner-operators and motor carriers complete required registrations accurately and stay compliant with federal regulations.
Related Articles:
- How to Start a Trucking Company
- Understanding the International Fuel Tax Agreement (IFTA)
- Understanding IRP (The International Registration Plan)
He is the Lead Content Specialist at FCCR, where he develops educational content focused on trucking compliance, DOT regulations, and FMCSA registration requirements. He works closely with compliance processes and industry systems to provide clear, accurate guidance for owner-operators and carriers.