What's the difference between an MC number and a USDOT number ? A USDOT number identifies carriers operating in interstate commerce while an MC number identifies a carrier who transports regulated goods for hire in interstate commerce. Generally, particulars that have been changed from their natural state are regulated goods taking an MC number . Determining whether an MC number versus a USDOT number is needed is made by the Federal Motor Carrier Safety Administratio, not the ND Highway Patrol. You can searching information by USDOT Number >> USDOT Number Lookup USDOT Companies Name >> Lookup USDOT Number by Company name MC Number Lookup >> MC Number Lookup MC Companies Name >> Lookup by Company name