What Does an MC Number Look Like? Format, Examples, and How to Look One Up

An MC number looks like MC-123456: the letters MC, a hyphen by convention, and a run of digits. It is FMCSA's docket number for an operating-authority registration, which is why it also comes in FF (freight forwarder) and MX (Mexico-domiciled carrier) flavors. This guide covers the format, what the prefixes mean, how many digits to expect, where the number shows up, how to look one up, and why the side of the truck says USDOT instead.

What Is the Format of an MC Number?

Prefix plus digits. In FMCSA's records the value is the docket number; on your operating authority certificate it is printed with the prefix. The hyphen and the space are formatting — MC-123456, MC 123456, and MC123456 all refer to the same docket, and a form that limits you to digits wants 123456. There is no check digit, no state code, and no letters after the number in the number itself.

The one thing an MC number is not is a USDOT number. A USDOT number is a plain integer with no prefix (FMCSA writes it “USDOT 1234567”), identifies the company in safety systems, and is free; the MC number identifies a granted authority under 49 U.S.C. §13902 and cost $300 to apply for. Our MC number vs USDOT number guide covers the difference in depth.

What Do MC, FF, and MX Mean?

• MC — motor carrier docket. Issued for property-carrier and passenger-carrier authority (the certificate under 49 CFR §365.101T) and for broker authority (the license). A broker's number is still an MC number; “MC-B” is industry shorthand for broker authority, not something FMCSA prints.
• FF — freight forwarder docket, issued with the forwarder permit. See freight forwarder authority.
• MX — Mexico-domiciled motor carrier docket, issued to carriers registered under the OP-1(MX) process. Our DOT vs MC vs MX comparison lays out who gets which.

One company can hold more than one docket — carrier authority and broker authority, for example — and FMCSA's records list each. See can I have multiple MC numbers for how that plays out.

How Many Digits Does an MC Number Have?

Legacy MC numbers were issued in sequence, so length roughly tracks age: an authority granted in the early 2000s often carries a six-digit number, and authorities granted in recent years carry seven. That pattern ended in May 2026. FMCSA says Motus randomizes all newly issued USDOT and operating-authority docket numbers to prevent fraud, and assigns one docket number per newly granted authority even when several are requested in one application. Existing numbers did not change, and multiple existing authorities keep sharing their docket. So a number's length or size no longer tells you when a carrier was authorized — the grant date in the FMCSA Register does.

Where Does Your MC Number Appear?

• Your operating authority certificate, permit, or license — the document FMCSA issues when the grant becomes effective (49 CFR §365.115(b)). See how to get the certificate.
• The FMCSA Register — FMCSA's daily list of registration decisions, under the grant notices and the certificate/permit/license section for the decision date.
• FMCSA's records — the Motus public search, which looks companies up by USDOT number or company name.
• Your Motus company account — alongside every registration action.
• Carrier packets and rate confirmations — brokers ask for it, and FMCSA has said the future USDOT suffix, if adopted, would be required on those business documents in its place.

It does not appear on your CDL, your IRP cab card, or your plates, and it is not required on the truck.

How Do You Look Up an MC Number?

1. Search by USDOT number. In FMCSA's Motus public search, enter the company's USDOT number. The record shows the USDOT status, the operating authority status (the authority types held, or not authorized), and the docket numbers.
2. Search by company name. If you only have a name, search by legal or DBA name in the same Motus public search.
3. You cannot search by MC number. Motus public search works by USDOT number or company name, so ask a carrier for its USDOT number rather than trying to look it up from the MC number alone.

If you are the carrier and FMCSA's records show a USDOT number but no MC number, you hold an identifier but no operating authority — the situation our do you need operating authority guide is written for.

MC Number vs USDOT Number on the Truck

The truck carries the USDOT number. 49 CFR §390.21T requires the legal name or a single trade name of the operating motor carrier and its identification number preceded by the letters “USDOT,” on both sides of the vehicle, in letters that contrast sharply with the background and are readable from 50 feet in daylight while the truck is parked. Painted or removable, it must be maintained. “Other identifying information may be displayed” if it is not inconsistent with that, so an MC number under the USDOT line is allowed and common; it is not required. FMCSA has also said the new Motus USDOT suffixes are not a vehicle-marking requirement.

A compliant door reads, for example: ACME FREIGHT LLC on one line and USDOT 1234567 below it, with MC-123456 optional beneath. A leased-on truck shows the operating carrier's name and USDOT number, not the owner-operator's — see leasing on vs your own authority.

What Are “MC Number Example” Searchers Usually Trying to Do?

• Fill in a form. A broker packet, factoring application, or load board asks for “MC number” and the field rejects the prefix. Enter the digits; put the USDOT number in its own field.
• Vet a carrier or broker. Look the company up by USDOT number or company name in FMCSA's Motus public search, confirm the legal name and docket number match the paperwork, and check that the authority is active for the right type with insurance on file.
• Find their own. Search FMCSA's Motus public search by USDOT number or company name; if no MC number is listed, the authority was never granted or has been revoked.
• Check whether they still need one. Yes for for-hire interstate work. FMCSA has proposed eventually retiring MC numbers for USDOT suffixes, but as of August 2026 that is a proposal — see are MC numbers going away.

Bottom line: MC-123456 is the shape — docket prefix, digits, no more. It lives on your certificate, in FMCSA's records, and in your Motus account; the truck shows your name and USDOT number under §390.21T. Fast Trucking Compliance charges $199 service fee + $300 FMCSA fee ($499 total) for the authority application that produces the number, itemized as two separate amounts.