MC Number vs DOT Number: What Each One Is

MC number vs DOT number comes down to purpose. A USDOT number is a safety registration: it identifies a company that operates commercial vehicles. An MC number is operating authority: it is what a company needs to haul regulated cargo or passengers for other people. They are two separate records, and an MC number is not the same as a DOT number.

A carrier can hold both, or only a USDOT number, and the one the federal rule asks for on your truck door is the USDOT number.

The two numbers side by side

USDOT number

• A safety identifier. FMCSA says companies subject to the safety requirements must also obtain a USDOT number (FMCSA).
• Preceded by the letters "USDOT" on the truck, with the carrier's name, on both sides (49 CFR 390.21).

MC number

• Operating authority, which FMCSA calls the docket number. It is often identified as an MC, FF or MX number depending on the type of authority granted, and it dictates the type of operation a company may run and the cargo it may carry (FMCSA).
• Not part of the federal marking requirement, as covered below.

FMCSA said in its 2000 marking rule that the MC number is used by FMCSA, process agents and insurance companies to track a for-hire carrier's application, insurance status and other requirements (Federal Register). It tracks the paperwork. The USDOT number is what identifies the company on the vehicle.

Who needs which

Start with the USDOT number. FMCSA says companies that operate commercial vehicles in interstate commerce must be registered and must have a USDOT number (FMCSA). Our guide on who needs a USDOT number covers the weight and use tests.

Operating authority is a second step for some. In general, a company needs interstate operating authority in addition to a USDOT number if it hauls federally regulated commodities owned by others for a fee, arranges that transport, or carries passengers for compensation (FMCSA).

FMCSA also lists who generally does not need one:

• Private carriers, meaning companies that transport their own cargo.
• For-hire carriers that haul only exempt commodities.
• Carriers operating only within a federally designated commercial zone.

If you are unsure which describes you, FMCSA's USDOT Wizard is built to point you to the registration you need.

Box trucks and the MC question

A box truck is a good example of why the answer depends on the work, not the truck. The same truck can be a private carrier hauling the owner's own goods, or a for-hire truck hauling a customer's freight. If it is a covered vehicle, the first generally needs a USDOT number and no MC number. The second may need both. Our box truck guide goes deeper, and you can confirm your situation with FMCSA.

What each costs to file

FMCSA lists a $300 filing fee for permanent operating authority, and says separate fees must be submitted for each kind of authority sought and that it does not refund application fees (FMCSA). Fees can change, so check FMCSA for the current amount before you apply. For USDOT registration costs, see how to get a USDOT number.

The numbers stay with one carrier

FMCSA says a USDOT number belongs to the same legal person forever and may not be sold, transferred, rented or leased (FMCSA fraud alerts). That matters when you buy a used truck. The number already on it belongs to the previous company, so it should not stay on your truck. Put your own name and number on instead.

What goes on the truck

Only the USDOT number is part of the federal marking rule. FMCSA's guidance says no marking requirement exists for displaying a carrier's MC number (FMCSA). The rule does allow other identifying information if it is not inconsistent with the required name and number, so many carriers add an MC line.

Our MC number on truck guide explains the history and the formatting. If you want both lines on one decal, see the USDOT + MC two-line decal, or order the MC Number decal by itself.