You need a commercial license if you're driving:
- any combination of vehicles with gross combined weight rating (GCWR) of 26,001 pounds or more (with the towed vehicle having a gross vehicle weight rating (GVWR) in excessive of 10,000 pounds)
- a single vehicle with a GVWR of 26,001 pounds or more (or any such vehicle towing another not in excess of 10,000 pounds)
- any vehicle designed to transport 16 or more persons (including the driver), or
- any vehicle required by federal regulations to have a placard while transporting hazardous materials.
See below to learn about the state-specific commercial driver's license requirements, including the costs and disqualifications.