A Class B license lets you drive single vehicles over 26,000 pounds, but not combinations of vehicles

A Class B license is a commercial driver's license (CDL) that permits you to operate a single large vehicle — typically a truck, bus, or straight truck — that weighs more than 26,000 pounds gross vehicle weight rating (GVWR). The key limitation is that you cannot tow a trailer or operate any combination of vehicles. If your work involves hauling cargo or passengers in a single large vehicle without a trailer attached, a Class B is what you need.

The distinction matters because the federal government and all 50 states regulate commercial driving separately from regular driving. A standard passenger license (Class D in most states) maxes out at vehicles under 26,000 pounds. Once you cross that threshold, you enter commercial territory, and the rules change — training requirements, medical certification, background checks, and testing all become mandatory.

Class B sits between Class A (which covers tractor-trailers and any combination of vehicles) and Class C (which covers smaller commercial vehicles). Most people who need a Class B are school bus drivers, dump truck operators, cement mixer drivers, or delivery drivers for large straight trucks.

Key Takeaways

  • A Class B license covers single vehicles over 26,000 pounds but excludes any trailer or combination of vehicles.
  • You must pass a written knowledge test, a skills test, and a medical examination to obtain a Class B.
  • Most states require you to hold a regular driver's license for at least one year before you can test for a Class B.
  • A Class B does not permit you to drive a tractor-trailer; that requires a Class A license.
  • Once issued, a Class B must be renewed every four to eight years depending on your state, and you must maintain medical certification throughout.

What vehicles you can and cannot drive with a Class B

With a Class B license, you can operate any single vehicle with a GVWR over 26,000 pounds. This includes straight trucks (the kind with the cargo area directly behind the cab), city buses, school buses, dump trucks, concrete mixers, and box trucks. The vehicle must be designed to carry passengers or cargo, and the weight limit applies to the vehicle itself, not what you load into it.

You cannot drive any vehicle towing a trailer, even a small one. You cannot operate a tractor-trailer combination, which requires a Class A. You also cannot drive a Class A vehicle with a Class B license, even if the tractor alone weighs less than 26,000 pounds — the combination rules override the single-vehicle rules. Some states add restrictions on passenger capacity; check your state's DMV handbook for specifics on whether you can drive a bus with more than 15 passengers.

The GVWR is the manufacturer's rating, not the actual weight of the vehicle on any given day. A truck rated at 28,000 pounds GVWR requires a Class B license even if you drive it empty. You can find the GVWR on a label inside the driver's door frame or in the owner's manual.

Medical certification and background requirements

Before you can test for a Class B, you must pass a Department of Transportation (DOT) medical examination performed by a certified medical examiner. This is not a standard physical; it includes vision and hearing tests, blood pressure screening, and a review of your medical history. The examiner is looking for conditions that could impair your ability to drive safely — uncontrolled diabetes, heart disease, sleep apnea, and certain medications can disqualify you.

You must also pass a background check that screens for serious traffic violations, felonies, and certain drug-related offenses. States vary on what disqualifies you, but a felony conviction within the past 10 years, a DUI within the past 5 years, or multiple traffic violations within a short period can block you from getting a CDL. Some states also check your employment history to verify you have not been fired from a commercial driving job for safety violations.

Once you pass the medical exam, you receive a Medical Certificate (also called a Medical Examiner's Certificate or MEC). This is valid for two years. You must carry it with you when you drive, and you must renew it before it expires. If your medical certificate lapses, you cannot legally drive a commercial vehicle, even if your Class B license itself is still valid.

Written test, skills test, and training requirements

To obtain a Class B license, you must pass two tests: a written knowledge test and a behind-the-wheel skills test. The written test covers vehicle inspection, safe driving practices, cargo handling (if applicable), and air brake systems if the vehicle you will drive has them. Most states allow you to study from the official CDL manual, which is free and available on the state DMV website. The test typically has 50 questions, and you must score at least 80 percent to pass.

The skills test has three parts: a pre-trip vehicle inspection (you walk around the truck and identify working and broken components), a basic control test (you maneuver the vehicle in a closed course), and a road test (you drive on public roads with an examiner). The road test lasts 30 to 45 minutes and covers acceleration, braking, turning, backing, and lane changes. You must use the actual vehicle you will be driving for work, or one of the same class and type.

Some states require formal training at a commercial driving school before you can test, while others allow you to study on your own. Training programs typically run three to six weeks and cost between $3,000 and $7,000. Even if your state does not require it, many employers will not hire you without a training certificate, so check with potential employers before you decide whether to attend.

How Class B differs from Class A and Class C licenses

The main difference between Class B and Class A is what you can tow. A Class A license covers any combination of vehicles where the trailer weighs more than 10,000 pounds — this includes tractor-trailers, doubles, and triples. A Class A driver can also drive any Class B vehicle. A Class B driver cannot drive a Class A vehicle, even if the tractor alone weighs less than 26,000 pounds.

A Class C license covers single vehicles under 26,000 pounds that carry 16 or more passengers (including the driver), or vehicles designed to carry hazardous materials. Class C is narrower than Class B in terms of weight but broader in terms of passenger capacity. A Class C driver cannot drive a Class B vehicle.

Some states also issue a Class D or regular passenger license with a commercial endorsement, which allows you to drive certain commercial vehicles without a full CDL. The rules vary by state, so check your state's DMV website to see what classes are available and which one matches your job.

Renewal, medical recertification, and maintaining your license

A Class B license is valid for four to eight years depending on your state. You must renew it before it expires, and you cannot renew online or by mail — most states require you to appear in person at a DMV office. When you renew, you must pass the written knowledge test again, though some states waive the skills test if you have held the license without violations.

Your medical certificate must be renewed every two years, and this renewal is separate from your license renewal. You must schedule an appointment with a certified medical examiner, pass the exam again, and submit the new certificate to your state DMV. If your medical certificate expires before your license does, you cannot legally drive a commercial vehicle until you renew it, even though your license is still valid.

If you accumulate certain traffic violations — speeding, reckless driving, or at-fault accidents — your Class B can be suspended or revoked. Some violations trigger automatic disqualification for a set period. A DUI or refusal to take a breath test can disqualify you for one to three years. Check your state's CDL disqualification rules to understand what violations affect your license.

Frequently Asked Questions

Can I get a Class B license if I have a DUI on my record?

Most states disqualify you from a CDL for one to three years after a DUI conviction. After that period, you may be able to test for a Class B, but you will need to pass the medical exam and background check. Some states have permanent disqualifications for certain offenses, so check your state's CDL handbook or contact your DMV directly.

Do I need to take a Class B test if I already have a Class A license?

No. A Class A license covers everything a Class B covers, plus tractor-trailers and vehicle combinations. If you hold a Class A, you can legally drive any Class B vehicle without additional testing. You only need to test for Class B if you do not already hold a higher class.

What happens if my medical certificate expires while I am driving?

You cannot legally operate a commercial vehicle once your medical certificate expires. If you are caught driving without a valid certificate, you can be cited and your vehicle may be taken out of service. Renew your medical certificate before it expires by scheduling an exam with a certified medical examiner.

Can I drive a school bus with a Class B license?

Yes, if the bus weighs more than 26,000 pounds and you do not have passengers under 16 years old. If you will transport school-age children, you will need a School Bus Endorsement (S) in addition to your Class B. This requires a separate written test and background check. Check your state's requirements, as some states have additional rules for school bus drivers.

How much does it cost to get a Class B license?

Testing and licensing fees vary by state, typically ranging from $50 to $200 for the written and skills tests. Medical exams cost $100 to $300. If you attend a commercial driving school, expect $3,000 to $7,000 for the course. Some employers cover training costs if you commit to working for them for a set period.