MCS-150 biennial update due date.

What the MCS-150 series is

Every entity with a USDOT number has to refresh its registration record on a fixed cycle. The regulation, 49 CFR 390.201(d)(3), says a person with a USDOT number must file an updated Form MCSA-1, the Unified Registration System online application, every 24 months. Carriers and the FMCSA forms guide still call the filing the MCS-150 update, and the guide lists three versions: the MCS-150 for a motor carrier, the MCS-150B for a motor carrier that transports hazardous materials, and the MCS-150C for an intermodal equipment provider. The same three forms are used for other changes to an existing registration, which is why the guide’s tables show them again for operation-type changes, address changes and re-application after revocation.

How the due date is worked out

The last digit of the USDOT number picks the month: 1 is January through 9 for September, and 0 is October. The update is due by the last day of that month. The next-to-last digit picks the year: odd means every odd-numbered calendar year, even means every even-numbered year. This is the same rule that the USDOT number checker applies; this page adds the form chooser and the filing route, so use whichever you need. Because the rule keys off the number and not the date you registered, a brand-new number can have a deadline within months.

Worked example (hypothetical number)

Take USDOT 9876543 counted from 20 October 2026. The last digit is 3, so March. The next-to-last digit is 4, which is even, so every even-numbered year. March 2026 has already passed, so the next deadline is 31 March 2028. A carrier with a number ending in 60, such as 1234560, ends in 0 for October and has 6 as the next-to-last digit, so it is due by 31 October 2026, eleven days after the count date. Change the count date to see the following cycle.

Where FMCSA says to file

In FMCSA’s Registration Forms Guide, the row for completing a biennial update lists the MCS-150 series, says you can make changes online through the FMCSA Portal using a Login.gov email account or submit a ticket with the forms attached, lists no processing fee, and asks for a government-issued ID plus any other supporting documents that depend on what changed. The guide states that the FMCSA Portal is now the only platform for online updates to existing registration accounts, and that applying for a new registration through the Unified Registration System has not changed. The guide also mentions Motus, FMCSA’s new registration system, so screens and links may move; follow the prompts on FMCSA’s own site.

Some changes cannot be made online. The guide says a change to company operation type requires a ticket. In its operating authority table, a name change request is a ticket with a $14 processing fee, while an address change can be made through the portal at no fee. Separately, 49 CFR 390.201(d)(4) requires a change of legal name, form of business or address to be reported within 30 days, and says that notice does not replace the 24-month update.

What happens if it is missed

Section 390.201(c)(1)(ii) says a person who fails to complete the biennial update is subject to penalties and to deactivation of its USDOT number. SAFER’s help text describes the visible result: an “Inactive USDOT Number,” described as inactive because the biennial update was not completed. SAFER’s help text cites 49 CFR 390.19(b)(4) for this, the rule’s old location. Section 390.201(g) now points to 390.19 only for procedures for Mexico-domiciled carriers, so if you read an older guide that says “390.19,” the current biennial rule is 390.201. The forms guide also has a row for re-application after revocation, with a separate form requirement if an active operating authority is linked to the number.

Common mistakes

• Using the wrong version. A carrier that transports hazardous materials files the MCS-150B, not the MCS-150.
• Counting from the registration date. The month and year come from the digits of the number.
• Filing a change of address and assuming the cycle is satisfied. The 30-day change notice does not replace the 24-month update.
• Assuming the year flips with the last digit. The last digit sets the month only.

Who this is for

Owner-operators and fleet compliance staff planning the filing, brokers checking whether a carrier’s inactive status could be a missed update, and anyone who inherited a USDOT number and does not know when it is due.

What this page does not cover

• It does not file anything, store your number or check whether the number is real.
• It does not cover UCR, Form 2290, IFTA or state registrations, which have their own cycles.
• It does not decide whether you need a USDOT number or operating authority.
• It does not state penalty amounts. The regulation text read for this page says only “penalties.”