A Class B CDL covers medium-duty trucks and buses, but not the largest rigs

A Class B Commercial Driver's License authorizes you to operate single vehicles with a gross vehicle weight rating (GVWR) between 26,001 and 33,000 pounds. The key difference from a Class A is that Class B does not allow you to tow a trailer weighing more than 10,000 pounds. If you need to haul heavier trailers or operate the largest trucks on the road, you need Class A instead.

Class B is the middle tier of commercial licensing. It covers delivery trucks, dump trucks, cement mixers, city buses, and straight trucks used in construction or local hauling. Many people pursue Class B because the testing is less complex than Class A, the training period is shorter, and the job market for Class B drivers remains steady in local and regional work.

The written test, skills test, and medical certification requirements are the same as for Class A — the difference is what you are permitted to operate, not how you prove you can operate it safely.

Key Takeaways

  • Class B allows you to drive single vehicles weighing 26,001 to 33,000 pounds, but you cannot tow a trailer heavier than 10,000 pounds.
  • You must pass a written knowledge test, a pre-trip inspection test, and a behind-the-wheel driving test administered by your state's DMV.
  • A current medical certificate from a Department of Transportation-certified examiner is required before you test and must be renewed every two years.
  • Most states require you to hold a valid regular driver's license for at least one year before you can test for a CDL.
  • Training programs vary in length from three to eight weeks depending on whether you attend full-time or part-time.

What vehicles you can and cannot operate with Class B

Class B covers any single vehicle — meaning no tractor-trailer combination — that weighs more than 26,001 pounds. This includes straight trucks like delivery vehicles, dump trucks, concrete mixers, and box trucks. It also covers buses designed to carry 16 or more passengers, including school buses and transit buses.

You cannot operate a Class A vehicle (tractor-trailer combinations or any vehicle towing a trailer over 10,000 pounds) with only a Class B license. If your job requires you to tow a heavy trailer, you must upgrade to Class A. You also cannot operate a Class A or Class B vehicle without the CDL, even if you own it — the license is required by federal law for any commercial vehicle in that weight range.

Some vehicles fall outside CDL requirements entirely. A pickup truck or van under 26,001 pounds does not require a CDL, even if you use it for business. Your state's DMV website lists the exact weight thresholds and vehicle types, because some states have additional restrictions based on passenger capacity or hazardous materials transport.

The written test and what it covers

The written test for Class B has two parts: the general knowledge test and the air brakes test. Both are administered by your state's DMV, usually at a testing center or your local office. You must pass both to move forward to the skills tests. Most states allow you to take them on the same day or on separate days.

The general knowledge test covers vehicle inspection, safe driving practices, cargo securement, and brake systems. It typically has 50 questions, and you must score at least 80 percent to pass. The air brakes test covers how air brake systems work, how to inspect them, and how to respond to brake failure. It has 25 to 30 questions and also requires 80 percent.

Your state's CDL manual is free and available online or in print at the DMV. Most people study for two to four weeks before testing. Many use practice tests available through the DMV website or third-party study sites. You can retake either test if you fail, but you may have to wait a set number of days (usually 7 to 14) before your next attempt.

The skills tests: pre-trip inspection and driving

After you pass the written tests, you schedule a skills test appointment with an examiner approved by your state. The skills test has two parts: the pre-trip inspection and the behind-the-wheel driving test. Both must be passed to receive your Class B license.

The pre-trip inspection test requires you to walk around and inspect a Class B vehicle — usually a dump truck or box truck — and point out safety-critical components. You explain what you are checking, why you are checking it, and what you would do if you found a problem. The examiner is listening for your knowledge of the vehicle, not your ability to fix it. This test usually takes 15 to 20 minutes.

The behind-the-wheel test takes 30 to 45 minutes. You drive a Class B vehicle through a predetermined route that includes city streets, highway driving, and parking maneuvers. The examiner watches for smooth acceleration and braking, proper mirror checks, safe lane changes, and correct handling of traffic situations. You do not need to be perfect, but you cannot make critical errors like running a red light, hitting an object, or losing control of the vehicle.

Medical certification and renewal requirements

Before you can test for a Class B CDL, you must obtain a medical certificate from a Department of Transportation-certified medical examiner. This is not your regular doctor — it must be someone on the FMCSA (Federal Motor Carrier Safety Administration) National Registry. You can find certified examiners through your state's DMV website or through the FMCSA website.

The medical exam checks your vision, hearing, blood pressure, and ability to operate a vehicle safely. You will be asked about your medical history, current medications, and any conditions that might affect your driving. The exam costs between $75 and $150, depending on your location and the examiner. Most exams take 30 to 45 minutes.

Your medical certificate is valid for two years from the date of issue. You must renew it before it expires, or your CDL becomes invalid. Some states allow you to renew by mail or online if your health status has not changed; others require an in-person exam. Check your state's rules when your certificate is within 90 days of expiration.

Training programs and how long they take

You are not required by federal law to attend a formal training program before testing for a Class B CDL, but most states strongly recommend it, and many employers will not hire you without a certificate from an accredited school. Training programs range from three weeks full-time to eight weeks part-time.

Full-time programs typically run Monday through Friday, 8 hours a day, and cost between $3,000 and $7,000. Part-time programs meet two to three evenings per week or weekends and cost between $2,000 and $5,000. Some programs include job placement information; others do not. Community colleges, private truck driving schools, and some unions offer Class B training.

A training program covers the same material as the written test but adds hands-on instruction in a real vehicle with an instructor. You will practice pre-trip inspections, backing maneuvers, and highway driving in a controlled environment before you test. Many schools also help you schedule your DMV test and provide a vehicle for the skills test if you do not have access to one.

Prerequisites and how long the process takes

Most states require you to hold a valid regular driver's license for at least one year before you can test for a CDL. Some states have no waiting period; others require two years. Check your state's DMV website for the exact requirement. You must also be at least 18 years old to hold a Class B CDL (21 if you plan to drive interstate).

The entire process from starting study to holding a Class B license typically takes four to twelve weeks, depending on whether you attend training and how quickly you pass the tests. If you study on your own and pass all tests on the first attempt, you might finish in four weeks. If you attend an eight-week part-time program, the timeline extends to eight weeks or longer.

Some people fail one or more tests and must retake them. Each retake adds one to two weeks. Budget extra time if you are working full-time while pursuing your license, because studying and training require significant hours outside your job.

Frequently Asked Questions

Can I get a Class B CDL if I have a DUI or traffic violation?

A DUI does not automatically disqualify you, but it may affect your ability to obtain insurance or be hired by an employer. Traffic violations are reviewed on a case-by-case basis by your state's DMV. Contact your state's CDL program directly to learn whether your specific violation will prevent you from testing.

Do I need air brakes experience before I test?

No, but if the vehicle you test in has air brakes, you must pass the air brakes test. If you test in a vehicle with hydraulic brakes only, you will receive a restriction on your license that prevents you from operating air brake vehicles. Most Class B vehicles have air brakes, so you should plan to test with air brakes.

What happens if I fail the behind-the-wheel test?

You can retake it after waiting the time required by your state (usually 7 to 14 days). You pay the testing fee again. Most people pass on the second or third attempt. If you fail multiple times, consider additional training or practice with an instructor before retesting.

Can I upgrade from Class B to Class A later?

Yes. You take the Class A written tests and skills test while holding your Class B license. You do not need to retake the medical exam if your certificate is still valid. The upgrade process is faster than obtaining Class B from scratch because you already understand CDL requirements.

Do I need to renew my Class B license?

Yes. Your CDL is valid for four to eight years depending on your state, but your medical certificate must be renewed every two years. If your medical certificate expires, your CDL becomes invalid until you renew it. Your state's DMV will send you a renewal notice before your CDL expires.