Glossary · updated October 31, 2026
MCS-150 Third-Party Filer
Also known as: MCS-150 Filing Service, MCS-150 Preparer
By Korey Sharp-Paar · Reviewed by the Fast Trucking Compliance team
Definition
An MCS-150 third-party filer is a private service that prepares a carrier’s MCS-150 update for a service fee. FMCSA charges no fee to file the MCS-150, so the service fee pays for convenience, accuracy review, deadline tracking and, commonly, help setting up Login.gov access for Motus. The update itself is submitted to FMCSA in Motus by the carrier or a filer it authorizes. A legitimate service says plainly that the government filing is free, itemizes its own fee, and is not affiliated with FMCSA or USDOT. Letters that imitate FMCSA notices to sell MCS-150 services are a known scam pattern.
Read more
MCS-150 Scam Notices: How to Tell a Real FMCSA Deadline From a MailerGovernment-style postcards and emails warn carriers their USDOT is about to be deactivated unless they pay immediately. Here is how to read them, and where legitimate paid filing services differ from the fakes.
Related terms
- Login.gov(FMCSA Login.gov)
- MCS-150(Motor Carrier Identification Report)
- Biennial Update(MCS-150 Biennial Update)