USDOT vs MC Number: What Each One Is and Which One Goes on the Door
Compliance reference · Last verified 19 September 2026
New carriers end up with two numbers and one door, and half the internet says both have to go on it. Here's what each number is and what the marking rule actually asks for.
The short answer
- USDOT number: identifies your company as a motor carrier. It's the one the federal marking rule puts on the door.
- MC number: your operating authority. It's needed by for-hire carriers hauling regulated freight across state lines, and by passenger carriers.
- The federal marking rule doesn't require the MC number on the truck. 49 CFR 390.21 asks for your name and “USDOT” plus your number.
- Many carriers show both anyway, because brokers and shippers look for the MC.
- FMCSA has proposed moving to USDOT-number-only registration. Until a final rule takes effect, MC numbers are still issued and used.
The USDOT number
The USDOT number is FMCSA's identifier for your company. The marking rule, 49 CFR 390.21(b)(2), requires:
The identification number issued by FMCSA to the motor carrier or intermodal equipment provider, preceded by the letters “USDOT.”
That number, with your legal or trade name, goes on both sides of the power unit, in a contrasting color, readable from 50 feet in daylight.
The MC number
The MC number (FMCSA also calls it a docket number) is operating authority. According to FMCSA, it's required for carriers that operate for hire and transport passengers or federally regulated commodities in interstate commerce. FMCSA lists who does not need it:
- Private carriers hauling their own cargo
- For-hire carriers hauling only exempt commodities
- Carriers operating only inside a federally designated commercial zone
So does the MC go on the door?
Not under the federal marking rule. When FMCSA rewrote the marking rule, it replaced the old ICC-era MC markings with the USDOT number. Nothing in 390.21 asks for an MC number on the vehicle.
There are still good reasons to add it. Brokers, shippers and gate guards often look for it, and a door that shows both answers the question before anyone asks. It's a choice, not a federal requirement. Some states have their own numbers for intrastate carriers (California's CA number, for example), so check your state if you run intrastate.
What we put on a standard door
- Legal name or trade name, exactly as filed with FMCSA
- USDOT 1234567
- MC 123456, if you want it
- City and state, if you want them
More detail: USDOT number size requirements · where to get your physical USDOT number · does a trailer need a DOT number?
USDOT + MC · shipped
$110
Free shipping to all 50 states · self-apply kit
- Name, USDOT and MC, both doors
- Cast vinyl, pre-spaced and taped
- To-scale proof before we cut
Fleet kits
From $203
2 to 4 trucks as a set · 5+ at $114 per truck
- One layout for the whole fleet
- Ships free, self-apply
- Proof before cutting
Nothing is cut until you approve your proof.
Sources
- 49 CFR 390.21 — Marking of self-propelled CMVs and intermodal equipment (eCFR)
- FMCSA — What is operating authority (MC number) and who needs it?
- FMCSA — Highlights of the Commercial Motor Vehicle Marking Final Rule
Last verified 19 September 2026 against the current eCFR text. FMCSA registration rules are under review. Check FMCSA for the current status of any MC-number changes.
JZAC Designs describes the standards we build to. We are a vinyl shop, not a compliance consultancy, and we do not advise on anyone's own regulatory obligations. Confirm final requirements for your situation with the agency that regulates it.