Some think of authority as having a USDOT number, but it's more than that, in interstate transportation it is the ability to move product or property that belongs to someone else for compensation. Having authority is often referred to as having an "MC number."

There are many different types of authority, but the more common are:

• Property for-hire,
• Passenger for-hire,
• Household goods,
• Broker, and 
• Freight forwarder. 

Authorities are not all inclusive, separate authority is needed for each type of service offered. For example, a for-hire over the road carrier that also wants to be able to resell its extra demand, will need both for-hire and brokerage authorities. There is a one-time $300 fee for each type of authority.

It is also possible for an entity that never operates CMVs, to have authority, but not have a USDOT number. Straight brokers are an example of this.

Independent drivers or owner operators may, or may not, have authority. If a driver is "leased on" to a carrier, the driver operates under the carrier's USDOT number and authority. However, if the driver obtains work from a broker or from shippers directly, then the driver needs both a USDOT number and authority. Some drivers that lease on with carriers also obtain their own authority to stay flexible and keep their options open.

The process to obtain authority is much longer than that to receive a USDOT number. There are no temporary trip permits available. If a carrier even occasionally hauls product or people for someone else, for-hire authority is needed. It's not uncommon for otherwise private carriers to obtain for-hire authority to generate revenue on back-hauls or help balance capacity vs. demand, especially during slow periods or seasons.

To have for-hire authority, a carrier also needs to designate process agents and demonstrate financial responsibility to the regulatory required levels. A process agent accepts legal paperwork on a carrier's behalf. An agent is required to be designated for each state of operation; however, a blanket designation may be made. A blanket designation either provides the service in all states or has relationships with other process agents. 

Most states require authority to intrastate movements. Some states require authority to make even one intrastate move, even if a carrier already has a USDOT number and interstate authority. Authority rules vary considerably from state to state. They differ in what what types of moves can be made, authority that is needed, and how strictly the states enforce their authority provisions.