Per the UCR Handbook, the Unified Carrier Registration program is unusual. It is essentially a state revenue program, but it is established under federal law. UCR policies are determined (to the extent not set out in federal law) by a governing board that consists of representatives of participating states, but also of private industry and the federal government. Fees charged under the UCR program are uniform across all the participating states and are set by the U.S. Secretary of Transportation upon the recommendation of the UCR Board.
The UCR program in many respects resembles other state tax programs. UCR is a base-state program; that is, every business subject to UCR requirements deals for UCR purposes only with the state in which it is based – commonly the state in which the business has its principal place of business. Interstate motor carriers of nearly every type are subject to UCR, as are interstate transportation brokers and freight forwarders, and companies that lease or rent rolling stock to interstate carriers.
Each entity subject to UCR is required to register annually with its base state and to pay an annual fee. The fees imposed on motor carriers and freight forwarders -- businesses that operate motor vehicles – are graduated through a system of brackets, based on the number of vehicles they have operated; brokers and leasing companies, which operate no vehicles themselves, pay a fee at the lowest bracket. No UCR credential is issued to a UCR registrant; enforcement is accomplished through on-line FMCSA data checks and various types of audit.