MCS-150 Form: Biennial Update Guide for Motor Carriers

When's the last time you updated your MCS-150? If you're not sure, it's probably overdue.

Every motor carrier with a USDOT number must update the MCS-150 form every two years under 49 CFR Section 390.19. It provides the FMCSA with your current company information, fleet size, driver count, and types of operations. Miss the deadline and FMCSA deactivates your USDOT number. Operating with a deactivated number? That's up to $16,000 per day in fines. And FMCSA doesn't send a ton of reminders before they pull the trigger.

What the MCS-150 Contains

The MCS-150 is FMCSA's census document for motor carriers. It captures:

• Legal business name and DBA (doing-business-as)
• Principal business address and mailing address
• Company contact information: phone, email
• Type of operation (interstate, intrastate, or both)
• Carrier type: for-hire, private, exempt, or government
• Number of power units owned, term-leased, and trip-leased
• Number of CDL and non-CDL drivers
• Types of cargo hauled (general freight, household goods, hazmat, etc.)
• Hazmat indicator noting whether you haul materials requiring a placard
• Company officers and ownership information

The FMCSA uses this data for safety oversight, enforcement targeting, and public disclosure on the SAFER system. Your MCS-150 data is public. When shippers, brokers, or insurance underwriters look up your USDOT number, they see exactly what you filed. Wrong or stale information stays visible until you fix it.

When Your Biennial Update Is Due

Your filing deadline depends on the last two digits of your USDOT number. FMCSA assigns filing months based on this schedule:

Your update is due every other year in that month. For example, if your USDOT number ends in 42, your filing month is March of every even-numbered or odd-numbered year (depending on when you originally filed).

You also need to update the MCS-150 within 30 days of any change to the information on file, regardless of whether your biennial update is due. Changes that trigger an update:

• Change of business address
• Change in company ownership or legal name
• Significant change in fleet size (adding or removing power units)
• Change in type of operation — like adding hazmat, or switching from private to for-hire
• Change in cargo types hauled

But the 30-day change requirement is the deadline that catches people. Carriers remember the biennial part and forget the rest.

How to File

Online (Recommended)

1. Go to portal.fmcsa.dot.gov (FMCSA Unified Registration System)
2. Log in with your USDOT PIN. If you don't have one, request a new PIN first.
3. Select "Update Registration" or "Biennial Update"
4. Review and update all fields
5. Certify the information and submit
6. Save or print the confirmation for your records

Online filing gives you immediate confirmation. The whole process takes about 15 minutes.

By Mail

1. Download the MCS-150 form from FMCSA's website or request a copy by calling (800) 832-5660
2. Complete all applicable fields
3. Sign and date the form
4. Mail to: FMCSA, USDOT Registration, 1200 New Jersey Avenue SE, Washington, DC 20590

Mail filings take significantly longer (generally about four to six weeks).

“The MCS-150 is the most overlooked compliance requirement we encounter. Carriers remember their drug testing deadlines and vehicle inspections, but forget about the biennial update until their USDOT number gets deactivated. Put it on the calendar, it takes 15 minutes to file online.”

What Happens If You Miss the Deadline

USDOT Number Deactivation

If you don't file your biennial update, FMCSA deactivates your USDOT number. That means:

• Your carrier registration is no longer active in FMCSA's systems
• You can't legally operate CMVs in interstate commerce
• Your SAFER record shows an inactive registration status
• Shippers, brokers, and insurers see the deactivation when they check your authority.

Penalties for Operating While Deactivated

Operating a CMV with a deactivated USDOT number is a federal violation. The FMCSA can impose civil penalties of up to $16,000 per day for each day you operate with a deactivated number.

Reactivation

If your USDOT number got deactivated for a missed biennial update, you can reactivate it by filing the overdue MCS-150 update through the FMCSA portal, verifying all information is current and accurate, and waiting for FMCSA to process the reactivation. Typically, one to three business days for online filings.

If your number has been inactive for a long time, the FMCSA may require additional steps before reactivation, including verification of insurance and operating authority status. The longer you wait, the harder it gets.

MCS-150 and DOT Audits

During a compliance review, FMCSA investigators check whether your MCS-150 is current as part of the general compliance factor. An overdue biennial update is a citable violation.

Auditors also compare your MCS-150 information against your actual operations. List 10 power units when you actually run 50, or fail to indicate hazmat operations, and you have a violation that may trigger a deeper review. It gets flagged often.

MCS-150 vs. Other FMCSA Filings

The MCS-150 takes minutes to file online, but carries serious consequences when it's missed. Build it into your compliance calendar alongside annual MVR reviews, random drug testing draws, and vehicle inspections.