CarrierScrub
What is an MC number?
An MC number is a Motor Carrier docket number. FMCSA assigned one each time it granted a specific operating authority to a carrier, broker or freight forwarder. It identifies that authority proceeding, not the company itself: the company's permanent federal identifier is its USDOT number, and one company can hold more than one docket number (MC for motor carriers and brokers, FF for freight forwarders, MX for Mexico-domiciled carriers).
FMCSA itself describes MC numbers as a tracking convenience that was never a statutory or regulatory requirement. That history matters for the phase-out question below.
How do I look up an MC number?
Enter it in the form above, with or without the MC prefix. CarrierScrub maps the docket number to the carrier's USDOT number in FMCSA's operating-authority records and runs the same checks a DOT number lookup runs: authority status, pending revocations, insurance on file against the required amount, and registration history at the carrier's phone number. The result shows the USDOT number, which is the one to write on the carrier packet because it does not change.
The government's own tools accept an MC number too. FMCSA's Motus public search and the SAFER Company Snapshot both take a docket number, and since 14 May 2026 Motus is where an authority's current insurance filings appear. FMCSA's legacy Licensing & Insurance (L&I) site stopped taking filings that day and holds the records from before it. They show the record; they do not weigh it.
Are MC numbers still required in 2026?
Yes. As of September 2026 FMCSA still issues MC numbers and they still appear on every operating-authority record. Several widely shared articles claim MC numbers were eliminated on 1 October 2025. FMCSA's own published position says otherwise, twice.
First, FMCSA's registration FAQ, last updated 21 May 2026, says existing MC numbers will not be replaced by USDOT numbers, and that the agency is considering phasing MC numbers out, with each type of operating authority instead shown as a suffix on the USDOT number. Considering is not the same as done. Second, the Federal Register notice announcing Motus, FMCSA's new registration system (91 FR 23144, 29 April 2026), states that the Phase II release will not include the elimination of MC and FF numbers, a change FMCSA deferred after stakeholders asked for more time. The USDOT suffixes exist inside Motus today for convenience only and do not yet appear on formal FMCSA correspondence.
What to do about it: key your carrier files on the USDOT number now, record the MC number alongside it, and treat any vendor telling you the MC number is already gone as out of date.
This is part of the same rollout as Motus, FMCSA's new registration system -- see what Motus is and what changed for the full picture.
MC number vs. USDOT number
| USDOT number | MC number | |
|---|---|---|
| Identifies | The company (carrier, broker, freight forwarder) | One grant of operating authority |
| Required by law | Yes, for every FMCSA-regulated entity (MAP-21) | No. Never a statutory requirement |
| How many per company | One, permanent | One per authority type; can be several |
| Where you see it | Truck door, every FMCSA record | Authority records, insurance filings, load documents |
| Future | Stays the sole identifier | FMCSA is considering a phase-out; not done as of 2026 |
| Use it for | Keying your carrier files | Confirming the specific authority being used |
What an MC number lookup doesn't tell you
The government record answers one question: does this docket number have active authority today? It does not tell you that FMCSA's revocation file shows a pending order against it, that the insurer has filed a cancellation dated next month, that the carrier has churned through four insurers, or that this USDOT number was registered two days after a carrier at the same phone number was revoked. Those are the facts CarrierScrub adds to the verdict, each with its date, and each stated as a fact rather than a conclusion.
Safety rating, out-of-service history and crash history come from FMCSA's SMS snapshot, dated to it -- never guessed. BASIC percentiles do not appear: FMCSA does not publish them for property carriers. A report never shows GO for a section it has no data for.
Where the data comes from
Operating authority, docket-to-USDOT mapping, insurance filings and revocation orders are published free under FMCSA's open data program. CarrierScrub checks them for the carrier you look up, using its current Motus record where FMCSA has one and FMCSA's legacy file, last updated 14 May 2026, where it does not. Every result names the record it used and that record's date. If FMCSA's record itself is wrong, the correction goes through DataQs, not through us.