The difference between Class A and Class B operator licenses

A Class A operator license lets you drive combination vehicles — a tractor unit pulling one or more trailers — with a gross vehicle weight rating (GVWR) of 26,001 pounds or more. A Class B operator license lets you drive single vehicles (not towing) with a GVWR of 26,001 pounds or more, or vehicles towing a trailer with a GVWR of 10,000 pounds or less. The key difference is that Class A covers heavy tractor-trailer rigs; Class B covers heavy single trucks and lighter towing combinations.

Both are commercial driver licenses (CDLs) issued by your state's Department of Motor Vehicles or equivalent agency. You cannot hold both at the same time — you hold one or the other. If you need to drive vehicles in both categories, you hold the Class A, which is the broader license. The written test, skills test, and medical certification requirements differ between the two, and so do the job roles they open.

Key Takeaways

  • Class A covers tractor-trailers and any combination vehicle over 26,001 pounds GVWR; Class B covers heavy single trucks and lighter towing setups.
  • Both require passing a written knowledge test, a skills test (pre-trip inspection, basic controls, and road test), and a Department of Transportation medical exam.
  • You must be at least 18 years old to hold either license in most states, though some states require 21 for interstate driving.
  • Class A opens more job roles (long-haul trucking, tanker hauling, flatbed) while Class B is common for local delivery, dump trucks, and concrete mixers.
  • Endorsements (hazmat, passenger, tanker) can be added to either license and require separate tests.

What vehicles each license class covers

Class A covers any combination of vehicles where the towed unit has a GVWR of more than 10,000 pounds. This includes the standard 18-wheeler (tractor pulling a 53-foot trailer), doubles (tractor pulling two trailers), and triples (tractor pulling three trailers, where legal). It also covers a single heavy truck towing a heavy trailer, as long as the combination total is over 26,001 pounds.

Class B covers single vehicles over 26,001 pounds GVWR — dump trucks, concrete mixers, straight-job box trucks, and tanker trucks — as long as they are not pulling a trailer, or pulling only a light trailer (10,000 pounds GVWR or less). A Class B driver can tow a small utility trailer or boat trailer but cannot tow a commercial cargo trailer.

The GVWR is the maximum weight the vehicle is designed to carry, including cargo and passengers. It is printed on the vehicle's door jamb or frame. If you are unsure whether a vehicle falls under Class A or Class B, check the GVWR and whether it is towing anything — that determines the class you need.

Written test and knowledge requirements

Both Class A and Class B require you to pass a written knowledge test administered by your state DMV. The test covers federal and state commercial driving regulations, vehicle inspection, cargo securement, braking systems, and safe driving practices. Most states allow you to study using the Commercial Driver License Manual, which is free and available online through your state's DMV website.

Class A and Class B written tests cover the same general knowledge, but Class A includes additional questions about combination vehicles — how air brakes work in a tractor-trailer, how to couple and uncouple trailers, and how weight distribution affects handling. Class B focuses more on single-vehicle operation and lighter towing scenarios. Both tests are typically 50 questions, and you must score at least 80 percent to pass.

You can take the written test at your local DMV office. Most states charge a fee between $10 and $50 per test attempt. Some states allow you to retake the test the same day if you fail; others require you to wait a set number of days before trying again.

Skills test: pre-trip inspection, basic controls, and road test

After passing the written test, you must pass a skills test, which has three parts. The pre-trip inspection requires you to walk around the vehicle (or combination of vehicles for Class A) and identify working and broken components — lights, tires, brakes, coupling devices, mirrors, and safety equipment. You must explain what you are checking and why. The examiner is testing whether you can spot safety defects before you drive.

The basic controls portion takes place in a closed course or parking lot. You perform maneuvers like straight-line backing, offset backing, alley dock, and parallel parking. For Class A, you also demonstrate coupling and uncoupling a trailer. For Class B, you show that you can handle a heavy single vehicle or light towing setup. You must complete these maneuvers without hitting cones or curbs and without excessive attempts.

The road test

Medical certification and physical requirements

Both Class A and Class B require a Department of Transportation (DOT) medical certificate. You must pass a physical exam conducted by a DOT-certified medical examiner. The exam checks your vision, hearing, blood pressure, and ability to operate a vehicle safely. You must have at least 20/40 vision in each eye (corrected or uncorrected) and be able to hear a whispered voice at three feet away.

The medical certificate is valid for two years (or one year if you are over 60 and driving interstate). You carry the certificate with you while driving and present it if stopped by law enforcement. If you fail the medical exam, you will not be issued a CDL until you address the medical issue and pass a retest.

Certain medical conditions — uncontrolled diabetes, heart disease, sleep apnea, or seizure disorders — may disqualify you or require a waiver from the Federal Motor Carrier Safety Administration (FMCSA). If you have a known condition, discuss it with the medical examiner before the exam so you understand whether you are may be able to access.

Age requirements and restrictions

You must be at least 18 years old to hold a Class A or Class B operator license in most states. However, if you want to drive interstate (across state lines), many states require you to be 21. Some states issue an intrastate-only CDL to drivers aged 18 to 20, which allows driving within that state only.

If you are under 21 and hold an intrastate CDL, you cannot legally drive a commercial vehicle across state lines, even if you meet all other requirements. Once you turn 21, you can upgrade to a full interstate CDL by notifying your DMV — no additional test is usually required.

Endorsements and additional qualifications

Both Class A and Class B licenses can carry endorsements, which are additional qualifications that allow you to haul specific cargo or passenger types. Common endorsements include Hazmat (hazardous materials), Tanker (liquid cargo in tank vehicles), Passenger (buses or vehicles carrying 16 or more people), and Double/Triple (multiple trailers, Class A only).

Each endorsement requires a separate written test. The Hazmat endorsement also requires a background check and fingerprinting through the Transportation Security Administration (TSA). Endorsements are not required to hold a CDL but are required to haul the specific cargo or carry the specific load. If your job involves hazmat or tanker work, your employer will typically require you to obtain the endorsement before you start.

Frequently Asked Questions

Can I upgrade from Class B to Class A without retaking all the tests?

No. To upgrade from Class B to Class A, you must pass the Class A written test and the Class A skills test (which includes coupling and uncoupling a trailer). You do not need a new medical exam if your current certificate is still valid. The upgrade process typically takes a few weeks and costs between $50 and $150 depending on your state.

What happens if I let my CDL expire?

If your Class A or Class B license expires, you must renew it through your state DMV. Most states allow you to renew by mail or online if you have not had any violations. If you have had violations or your medical certificate has expired, you may need to retake the written test or medical exam. Renewal fees vary by state but typically range from $30 to $100.

Do I need a Class A or Class B to drive a pickup truck with a trailer?

Not necessarily. If the pickup truck and trailer combination has a GVWR under 26,001 pounds, you can drive it with a regular driver license. You need a CDL only if the combined GVWR exceeds 26,001 pounds. Check your truck's door jamb and the trailer's specifications to determine the combined GVWR.

Can I hold a Class A and Class B at the same time?

No. You hold one class or the other. If you need to drive both tractor-trailers and heavy single trucks, you hold a Class A license, which covers both. You cannot hold both licenses simultaneously.

What disqualifies you from getting a CDL?

Serious traffic violations (reckless driving, hit-and-run, using a vehicle to commit a felony), DUI convictions, and certain medical conditions can disqualify you. Some states also disqualify drivers with multiple moving violations within a set time period. Your state DMV can tell you whether a specific violation or condition affects your may be able to access.