MCS-150

MCS-150 Biennial Update Guide

✦ The quick answer

The MCS-150 is the form carriers use to update their USDOT number information, and the FMCSA requires you to refile it every 24 months based on the last two digits of your USDOT number, even if nothing changed. Miss the update and the FMCSA can deactivate your USDOT number, which can shut down your operating authority.

✓Built on live FMCSA + IRS rules✓Free check, no credit card✓You always review & submit

Updated Jun 2026·4 min read

Who must file

Any carrier with an active USDOT number must keep its MCS-150 (Motor Carrier Identification Report) current. This includes interstate carriers, many intrastate carriers in states that require a USDOT number, private fleets, and for-hire operators. You file an MCS-150 when you first register for a USDOT number, again on your assigned biennial (every-24-month) schedule, and any time key business information changes, such as your company name, address, number of vehicles or drivers, mileage, or operation type. If you have stopped operating, you also use an MCS-150 to deactivate the number.

Deadline

Your update is due every 24 months on a schedule set by the last two digits of your USDOT number. The next-to-last digit tells you whether you file in an odd-numbered year (odd digit) or an even-numbered year (even digit), and the last digit tells you which month: 1 = January, 2 = February, and so on through 9 = September, with 0 = October. For example, a USDOT number ending in 35 updates in March of odd years. The update is due by the last day of that month, and you should file even if none of your information has changed. Always confirm your exact due month on the FMCSA site, because your schedule does not move just because you filed early.

Penalties

If you do not file your MCS-150 on time, the FMCSA can deactivate your USDOT number. A deactivated number can stall your ability to operate, cause problems at roadside inspections and weigh stations, and disrupt your operating authority (MC number) and related registrations such as UCR and IRP. Federal rules also allow civil penalties for failing to file or for filing materially false information. You can reactivate a deactivated USDOT number by submitting a current MCS-150, but that takes time you may not have when a load is waiting, so it is far easier to file on schedule.

What the MCS-150 actually does

The MCS-150 is the form that ties your business to your USDOT number. The FMCSA uses the information on it to build your safety profile, size your operation, and decide how you are monitored. That is why it asks for your legal and DBA names, principal address, the number of power units and drivers you run, your annual mileage, your cargo and operation classifications, and whether you carry hazardous materials.

Keeping this accurate matters beyond compliance. Inaccurate vehicle and mileage counts can throw off your safety measurement scores and even how often you draw inspections. When your numbers reflect reality, your record reflects reality too.

How your 24-month schedule is set

Your filing month is not random and you do not get to pick it. The FMCSA derives it directly from your USDOT number.

The last digit sets the month: 1 is January, 2 is February, 3 is March, 4 is April, 5 is May, 6 is June, 7 is July, 8 is August, 9 is September, and 0 is October.

The next-to-last digit sets the year: if it is odd, you file in odd-numbered years; if it is even, you file in even-numbered years. So a USDOT number ending in 47 files in July of odd years, and one ending in 80 files in October of even years. Write your month down once and it never changes for that USDOT number.

When to file outside your biennial date

The 24-month cycle is the minimum, not the only trigger. You should submit an updated MCS-150 within a short window any time your operation changes in a way the FMCSA tracks. Common reasons include a change of company name or DBA, a new principal place of business or mailing address, a meaningful change in fleet size or driver count, a change in the type of cargo you haul, adding or dropping hazmat, or ceasing operations entirely.

Filing an off-cycle update does not reset your biennial schedule. Your assigned month stays the same, so keep a reminder for it regardless of any interim updates you make.

How QuickTruckTax helps you get it right

QuickTruckTax is not a filing service and does not submit anything to the FMCSA for you. What we do is help you understand, prepare, and validate your MCS-150 update so it goes in clean.

We walk you through calculating your exact due month from your USDOT number, build a checklist of the fields you will need before you sit down to file, and help you sanity-check details like vehicle counts, mileage, and operation classification so they match your records. Then you submit the update yourself through the official FMCSA system. This is general guidance, not legal or tax advice, so confirm specifics with the FMCSA before you file.

If your USDOT number was already deactivated

A deactivated USDOT number is recoverable. The usual fix is to file a complete, current MCS-150 to bring your record up to date, after which the FMCSA can reactivate the number. Because reactivation is not instant, do not wait until you are at a weigh station to discover the problem.

If your operating authority, UCR, IRP, or IFTA status is tangled up with the deactivation, sort those out in parallel so you are not held up by a single missing piece. Verify your current status anytime by looking up your USDOT number on the FMCSA site.

Ready to run the numbers?

Estimate it in seconds — then have the AI check your details.

Find your MCS-150 due date

Frequently asked questions

How do I know which month my MCS-150 is due?+

Look at the last two digits of your USDOT number. The last digit is the month (1 = January through 9 = September, 0 = October). The next-to-last digit tells you the year: odd means odd-numbered years, even means even-numbered years. A number ending in 52 updates in February of even years. Confirm the date on the FMCSA site to be sure.

Do I have to file even if nothing changed?+

Yes. The biennial update is required every 24 months regardless of whether your information changed. Skipping it because nothing is different is one of the most common reasons carriers get their USDOT number deactivated. File on your assigned month every cycle.

What happens if I miss my MCS-150 deadline?+

The FMCSA can deactivate your USDOT number. That can stall your operating authority, create issues at inspections and weigh stations, and ripple into other registrations like UCR and IRP. You can reactivate by filing a current MCS-150, but it takes time, so filing on schedule is far easier.

Is there a fee to file the MCS-150 update?+

The biennial MCS-150 update itself is generally filed directly with the FMCSA without a filing fee, but related registrations such as UCR or new operating authority have their own costs. Verify the current requirements and any charges on the official FMCSA site before you file.

Does filing early change my next due date?+

No. Your biennial schedule is fixed by your USDOT number's last two digits and does not move when you file early or submit an off-cycle change. Your next required update is still 24 months out on your assigned month, so keep that reminder.

Can QuickTruckTax file the MCS-150 for me?+

No. We help you understand your due date, prepare the information, and validate your entries so your update is accurate, but you submit it yourself through the official FMCSA system. This is general guidance, not legal advice, so confirm details with the FMCSA.

dot compliance ucr registration irp guide boc 3 guide

How this works: QuickTruckTax helps you understand, prepare, and validate your filing. We are not a filing service and never submit forms on your behalf — you always do the final review and submission. Figures here are estimates for guidance only and are not legal or tax advice. Confirm current rules, fees, and deadlines with the IRS, FMCSA, or your state agency.