--- title: "CDL: Definition and Meaning | NPSA" description: "A CDL is a commercial driver's license, required to drive certain commercial motor vehicles. A driver must pass knowledge and skills tests. States issue CDLs." url: https://npsa.preview.multisites.ai/glossary/cdl publisher: National Portable Storage Association (NPSA) phone: "(816) 960-6552" email: info@npsa.org --- Trucking and regulatory # CDL A CDL is a commercial driver's license, required to drive certain commercial motor vehicles. A driver must pass knowledge and skills tests. States issue CDLs. FMCSA sets the federal standards and does not issue them. Some vehicles also need extra endorsements. ## Why it matters A CDL is the license a driver needs to operate heavy trucks, such as many container delivery rigs. The class depends on vehicle weight and what it tows. Some vehicles also need endorsements, such as for tankers or hazardous materials. A common mistake is to assume a regular license is enough for a large tilt-bed or tractor-trailer. Another is to think one state's rules apply everywhere. Drivers get a CDL from their home state, and it is illegal to hold more than one. Operators should check each driver's class and endorsements against the truck. Check the FMCSA site and your state agency for current rules. [Read: Safety and compliance for container delivery: DOT, FMCSA, CDL and OSHA](https://npsa.preview.multisites.ai/guides/dot-fmcsa-osha-compliance) Definition source: [fmcsa.dot.gov](https://www.fmcsa.dot.gov/registration/commercial-drivers-license) ## Related terms [### Class A CDL A Class A CDL is the commercial license for combination vehicles. Federal rules cover any combination with a gross combination weight rating of 26,001 pounds or more, where the towed unit has a GVWR over 10,000 pounds. It is the class for most tractor-trailer rigs.](https://npsa.preview.multisites.ai/glossary/class-a-cdl)[### Class B CDL A Class B CDL is the commercial license for heavy straight vehicles. Federal rules cover a single vehicle with a GVWR of 26,001 pounds or more, or one that tows a vehicle of 10,000 pounds GVWR or less. It covers many heavy single-unit trucks.](https://npsa.preview.multisites.ai/glossary/class-b-cdl)[### FMCSA FMCSA is the Federal Motor Carrier Safety Administration, an agency within the U.S. Department of Transportation. It writes and enforces safety rules for commercial motor vehicles and carriers, and it handles registration for interstate carriers. Its rules are in the Federal Motor Carrier Safety Regulations.](https://npsa.preview.multisites.ai/glossary/fmcsa)[### DOT medical card A DOT medical card is the common name for the Medical Examiner's Certificate. A certified medical examiner issues it to a commercial driver who passes the federal physical. FMCSA requires it for drivers of vehicles over 10,000 pounds gross vehicle weight rating that operate in interstate commerce.](https://npsa.preview.multisites.ai/glossary/dot-medical-card)[### drug and alcohol testing Drug and alcohol testing is the federal program that tests safety-sensitive transportation workers. For commercial truck drivers who must hold a CDL, FMCSA rules in 49 CFR Part 382 set who is tested and when. The DOT-wide rule in 49 CFR Part 40 sets how each test is done.](https://npsa.preview.multisites.ai/glossary/drug-and-alcohol-testing)[### GVWR GVWR is gross vehicle weight rating. It is the maximum loaded weight of a single motor vehicle, as set by the manufacturer. It includes the vehicle, fuel, driver, cargo and equipment. It is printed on the vehicle's certification label and set by the maker.](https://npsa.preview.multisites.ai/glossary/gvwr) [All 220 terms](https://npsa.preview.multisites.ai/glossary) For the industry ## Grow your portable storage business with NPSA Members get event rates, the Community Forum, the directory listing and leads from this website. [Join NPSA](https://npsa.preview.multisites.ai/join-us)[See member benefits](https://npsa.preview.multisites.ai/member-benefits) Need storage? ## Get quotes from NPSA member companies Tell us what you need and where. A member company that serves your area will contact you. [Request a quote](https://npsa.preview.multisites.ai/request-a-quote)[Which unit do I need?](https://npsa.preview.multisites.ai/find-storage)