from the Maryland Department of Health Link
Maryland law requires that every registered truck over 10,000 pounds, truck tractor and bus operated on public roads, unless specifically exempt*, must display either a USDOT Number or a Maryland-issued motor carrier identification number. If you are a motor carrier who is not required to have a USDOT Number because your vehicles do not leave Maryland and you do not handle interstate cargo, you must obtain a Maryland identification number (MD DOT #) and display it on your trucks, truck tractors and buses.Motor carriers that are interstate or intrastate must apply for a USDOT Number from the Federal Motor Carrier Safety Administration (FMCSA). Applicants may apply online at
USDOT Numbers and MD DOT Numbers must be displayed in compliance with Federal Motor Carrier Safety Regulations (FMCSR) part §391.21. Motor carriers that are not in compliance are subject to fines.
*The following vehicles, if only operated intrastate, are exempt: Farm trucks, farm truck tractors, farm-area motor vehicles, emergency vehicles, vehicles primarily transporting money or commercial paper, vehicles owned or operated by the State or local government, and vehicles within 15 days of their purchase.
We're available on the following channels.