Commercial vehicles/CDL

Rules and regulations


U.S. DOT number

Who needs a U.S. DOT number and how to get one

Motor carriers operating commercial vehicles across state lines will find helpful information and assistance at the Federal Motor Carrier Safety Administration's Online Registration and Compliance Assistant website.

Motor carriers who are domiciled in Iowa and operate in for-hire intrastate commerce within Iowa also need to obtain a USDOT-IA number. Intrastate for-hire carriers need to contact the Iowa DOT's Office of Vehicle & Motor Carrier Services at 515-237-3268 for an application and assistance in obtaining intrastate operating authority and a USDOT-IA number.

A motor carrier who already has a USDOT number for interstate commerce will not be issued a second USDOT number, but must still obtain intrastate operating authority for loads transported within Iowa

Trailer hitch requirements

The Iowa Department of Transportation's (DOT) Office of Motor Vehicle Enforcement (MVE) is reporting an increase in questions related to safe and lawful trailer hitch attachment in Iowa. The majority of questions relate to whether you must remove the trailer hitch from your vehicle when a trailer is not attached. Iowa DOT's MVE Major Ned Lewis clarified that there is no Iowa law that requires a hitch be removed when a trailer is not in tow.