To obtain a CDL for interstate commerce, an applicant must be at least: Question To obtain a CDL for interstate commerce, an applicant must be at least: Answers 15 years old. 18 years old. 21 years old. 25 years old. Explanation You must be at least 21 years old and have at least one year of driving experience to be licensed to drive in interstate commerce or to transport hazardous materials.
