FMCSA has proposed retiring MC numbers for USDOT-number suffixes, but as of August 2026 nothing is final: Motus still issues MC numbers and no rule is out.
Not yet. FMCSA has proposed to stop assigning MC numbers and identify every registration by the USDOT number plus a suffix, but that change is only under consideration for a future rulemaking. As of August 2026 no proposed rule has been published, Motus still issues MC/FF/MX docket numbers, existing MC numbers stay valid, and a for-hire interstate carrier still needs operating authority under 49 U.S.C. §13902.
TL;DR
Not yet. FMCSA has proposed to stop assigning MC numbers and identify every registration by the USDOT number plus a suffix, but that change is only under consideration for a future rulemaking. As of August 2026 no proposed rule has been published, Motus still issues MC/FF/MX docket numbers, existing MC numbers stay valid, and a for-hire interstate carrier still needs operating authority under 49 U.S.C. §13902.
Search “are MC numbers going away” and you get a stack of posts announcing that FMCSA has “eliminated” MC numbers. It has not. What FMCSA has done is publish a proposal to stop assigning them, launch a registration system that still issues them, and say the retirement will go through a public rulemaking first. This guide separates what is final from what is proposed, with the primary sources, as of August 2026.
What Has FMCSA Actually Proposed?
FMCSA says it has proposed to stop assigning MC numbers. The USDOT number would become the single identifier for every registrant, and each registration a company holds — property carrier, broker, household goods, freight forwarder, passenger — would show up as a letter suffix on that USDOT number inside FMCSA's systems. The agency ties this to MAP-21, the 2012 highway law that made a USDOT number mandatory for every entity it regulates, including brokers and freight forwarders that never owned a truck. The agency's running statement is the registration modernization FAQ on fmcsa.dot.gov.
Two details in FMCSA's explanation matter for anyone holding an MC number today. First, the agency's position is that MC numbers were never a statutory or regulatory requirement — they were docket numbers used to track proceedings on a single operating-authority registration, not identifiers of the company. Second, FMCSA has said that if it stops issuing MC numbers, existing MC numbers will not be replaced by USDOT numbers. The plan under consideration is a phase-out of new issuance, not a swap.
The suffix scheme FMCSA has published: C for property-carrier operating authority, V for private carrier, P for passenger authority, H for household goods, B for broker, F for freight forwarder, E for enterprise, X for MX long-haul, Z for MX commercial zone, N for non-North America domiciled, and R for intrastate carrier. A property carrier that also holds household-goods authority would read as USDOT 1234567CH; a broker as 1234567B. FMCSA is explicit that suffixes are not a vehicle-marking requirement.
What Changed When Motus Launched, and What Did Not
Motus: USDOT Registration Systemis the vehicle for all of this, and its launch is where the “MC numbers are gone” rumor took hold. The record says otherwise. FMCSA's Federal Register notice announcing Motus (91 FR 23144, April 29, 2026; docket FMCSA-2026-1255 per the May 6 correction at 91 FR 24643) states that, in response to stakeholder feedback, the Phase II release does not include safety registration, the elimination of MC/FF numbers, or changes to the BOC-3 filing process. Phase I opened December 8, 2025 for supporting companies; Phase II — everyone else — followed the May 14, 2026 shutdown of URS and the FMCSA Portal's registration options.
What Motus did change about docket numbers is narrower. Newly issued USDOT and docket numbers are randomized to fight fraud. Each new authority granted in Motus gets its own docket number, even when several were requested in one application. And Motus displays the new USDOT suffixes for first-time registrants inside their company account. Existing numbers did not change, the MC/MX/FF prefixes continue, and per the notice the suffixes are visible in the system for convenience but do not appear on formal agency correspondence such as letters and orders.
Where Does the Rulemaking Stand as of August 2026?
The April notice said FMCSA anticipated issuing a rulemaking in spring 2026 proposing, among other things, to require Motus for all registrants and to eliminate the legacy forms (the OP-1 series, MCS-150, BOC-3 and others). Spring passed without it. We checked the Federal Register on August 16, 2026: FMCSA's proposed rules published since April cover UCR fees, CDLIS fees, and English-language proficiency — nothing on docket numbers or the Unified Registration System. The Unified Agenda entry for the rule (RIN 2126-AB56, “MAP-21 Enhancements and Other Updates to the Unified Registration System”) projects a proposed rule for July 2026; agenda dates are estimates, and this one has slipped.
Some history explains the caution. FMCSA's original URS final rule in 2013 (78 FR 52608) said the new system would discontinue issuance of MC, MX, and FF numbers. Implementation dates were pushed in 2015 and 2016, and the URS registration scheme was suspended effective January 14, 2017 (82 FR 5292) because the IT systems were not ready. The 2026 proposal is that same idea, thirteen years on, now attached to a system that finally exists. The hub's 2026 URS final-phase guide tracks the wider set of rule changes riding along with it.
What Would Change for Existing MC Holders?
If the proposed rule is published, adopted, and takes effect, FMCSA's stated design is that your USDOT number plus suffixes becomes how the agency identifies your registrations, while the MC number is retired from issuance rather than deleted from history. In practice SAFER and L&I already key everything to the USDOT number, and the docket record and its history stay attached to it. Your BOC-3, your insurance filings, and your new-entrant status live on the registration, not on the letters M and C.
The one place FMCSA has flagged a real-world change: it says suffixes would be required by statute for identification on documents for business transactions involving for-hire carriers, brokers, and freight forwarders — think rate confirmations and broker-carrier agreements. That would replace the habit of writing “MC 123456” on paperwork with something like “USDOT 1234567C.” Truck marking is unaffected because 49 CFR §390.21T already requires the USDOT number, not the MC number, on the vehicle. Any of this would arrive with a comment period and an effective date; none of it is in force today.
How Do Brokers, Factors, and Insurers Verify You in the Meantime?
Nothing about vetting has changed. Brokers still search you by MC or USDOT number on SAFER and the L&I site, look for “AUTHORIZED FOR” Property (or Household Goods, Passenger, Broker) and an active BMC-91 filing, and pull your record into vetting tools that key on both numbers. Factoring companies still ask for the operating authority letterand a certificate of insurance. Insurers still file the BMC-91 or BMC-91X against your registration in FMCSA's system. If an onboarding form asks for your MC number, give it; if it asks for your USDOT number, give that too. Our guide to what an MC number looks like covers which is which.
Should You Still Apply for MC Authority Now?
Yes, if you plan to haul for hire across state lines. The legal requirement is registration under 49 U.S.C. §13902for carriers, §13903 for freight forwarders, and §13904 for brokers, and it applies regardless of what the identifier printed on the grant is called. Operating without it exposes you to civil penalties under 49 U.S.C. §14901. Motus issues an MC docket number with every new property or broker authority today, and FMCSA has said existing numbers stay put if issuance ends. Waiting for a hypothetical USDOT-only regime means not running — and if the rule ever takes effect, a carrier registered under an MC number will be in the same position as one registered the day after.
The mechanics have not moved either: the $300 FMCSA fee per authority under 49 CFR §360.3T(f)(1), the BOC-3and insurance filings due within 20 days of the FMCSA Register notice under §365.109T, and the 18-month new-entrant period under Part 385 Subpart D. FastTruckAuthority files the authority application for a flat $199 service fee plus the $300 FMCSA fee ($499 all-in). If your authority is inactive rather than new, that is a reinstatement question, handled by our sister site.
How to Track the Change
- Federal Register. Watch for an FMCSA proposed rule under RIN 2126-AB56; the comment period is the point at which carriers, brokers, and load boards get to say how a USDOT-plus-suffix world should work.
- fmcsa.dot.gov.The registration-modernization FAQ answers “Will FMCSA stop issuing MC Numbers?” directly, and the “About FMCSA Registration Changes” page lists what is under consideration versus what shipped.
- Your Motus account. FMCSA notices and emailed letters land there; that is also where a first-time registrant will see suffixes displayed.
- Docket FMCSA-2026-1255. The Motus availability notice on regulations.gov; the eventual proposed rule will get its own docket.
Bottom line: as of August 2026, MC numbers are proposed for retirement, not retired. Motus still issues them, existing ones stay valid, and no proposed rule has been published. Register the way the law requires today; if the identifier changes later, FMCSA has said your registration comes with you.