If you are operating in the transportation industry, you are expected to have a USDOT number. Without this number, there is no way you can run a trucking business in the US.
After getting your USDOT number, there are other things you need to do from time to time to stay compliant with FMCSA. One of such is the MCS 150 e -filing.

MCS 150 form, also known as Motor Carrier Identification Report, is a filing that updates your USDOT number. Through this form, FMCSA will get precise information about your business. This information could include the number of vehicles in your fleet, what your vehicle is designated for (whether passenger carrier or hazardous materials vehicle), and your mileage.

Filing this information makes it easy for FMCSA to authenticate whether the info connected with your USDOT number is accurate. As long as you are a motor carrier and have a DOT number, you must file an MCS 150 form every two years, and that is why it is called the biennial MCS 150 update.
You should file for an update regardless of whether there are changes or not. If you add more trucks to your fleet, change your business name, need to file an MCS 150 update, and your information must be accurate.

What is a USDOT Number?

Companies that operate commercial vehicles transporting passengers or hauling cargo in interstate commerce must be registered with the FMCSA and have a USDOT Number. Also, commercial intrastate hazardous materials carriers who carry types and quantities requiring a safety permit must register for a USDOT Number.
The USDOT Number serves as a unique identifier when collecting and monitoring a company's safety information acquired during audits, compliance reviews, crash investigations, and inspections.
Do I Need a USDOT Number?
You are required to obtain a USDOT number if you have a vehicle that:
is used to transport the types and quantities of hazardous materials requiring a safety permit in intrastate commerce
or
Has a gross vehicle weight rating or gross combination weight rating, or gross vehicle weight or gross combination weight, of 4,536 kg (10,001 pounds) or more, whichever is greater; or
Is designed or used to transport more than eight passengers (including the driver) for compensation; or
It is designed or used to transport more than 15 passengers, including the driver, and is not used to transport passengers for compensation;
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