What Is a CDL License?
TL;DR
A CDL (Commercial Driver's License) is a special license required to drive large commercial vehicles in the US. There are 3 classes: Class A (semi-trucks, tractor-trailers), Class B (straight trucks, buses), and Class C (vehicles carrying 16+ passengers or hazardous materials). You need a CDL if your vehicle exceeds 26,001 lbs GVWR or carries passengers or hazmat.
CDL Explained: What It Is and Who Needs One
A Commercial Driver's License (CDL) is a federal and state-issued license that allows you to legally operate large commercial motor vehicles (CMVs) in the United States. CDLs are regulated by the Federal Motor Carrier Safety Administration (FMCSA) and issued by individual states. You need a CDL if you drive:
- Vehicles with a Gross Vehicle Weight Rating (GVWR) over 26,001 lbs
- Vehicles towing a trailer with GVWR over 10,001 lbs (if combined weight exceeds 26,001 lbs)
- Vehicles carrying 16 or more passengers (including the driver)
- Vehicles transporting hazardous materials requiring placards
The 3 CDL Classes: A, B, and C
CDLs are divided into three classes based on what vehicles you can drive:
- Class A CDL: Semi-trucks, tractor-trailers, livestock carriers, flatbeds — any combination vehicle over 26,001 lbs with towed unit over 10,001 lbs. Highest earning potential.
- Class B CDL: Straight trucks, large buses, dump trucks, delivery trucks — single vehicle over 26,001 lbs. Class B holders can also drive Class C vehicles.
- Class C CDL: Vehicles carrying 16+ passengers or hazardous materials but not covered by Class A or B. Includes small HazMat vehicles, airport shuttles.
CDL Endorsements — What They Unlock
Endorsements are add-ons to your CDL that let you drive specialized vehicles or cargo. Key endorsements include:
- H — Hazardous Materials: Required to transport HazMat cargo
- N — Tank Vehicles: Required to drive tanker trucks
- P — Passenger: Required to carry 16+ passengers (buses, shuttles)
- S — School Bus: Required to drive school buses
- T — Doubles/Triples: Required to pull double or triple trailers
- X — Combination of N and H (tank + hazmat)
Start Preparing for Your CDL Today
The CDL knowledge test is the first step — and one of the most important. Our free 2026 practice tests cover every topic from the General Knowledge test to specialized endorsements.
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