Department of Transportation Numbers and What They Mean

The FMCSA, or the Federal Motor Carrier Safety Administration, enforces a number of regulations to ensure road safety. One of their requirements is that moving companies register for a US Department of Transportation number. The US DOT number is a way for the government to identify a particular carrier when collecting information from audits, compliance reviews, inspections, and other data sets. It's also used as an organizational tool for enforcing and monitoring safety regulations.
When applying for a US DOT number, a company will be enrolled in a program called "New Entrant Safety Assurance Program." During this 18-month education program, companies will learn all about carrier safety and hazardous material regulations. In order to get a permanent US DOT number, the carrier must maintain safe operations during the 18 months of the program and pass a safety audit. While not all moving companies are required to attain a US DOT number, any long-distance mover that performs interstate moves is required to have one.

TIP: Though many local movers aren't required to have a US DOT number, 28 states require that they do have this federal identification.
If you are moving a long distance, you should use a company with a US DOT number, regardless of whether or not you are crossing state lines. There are a few simple ways to see if your mover has one. First, you can check the FMCSA SAFER system at safer.fmcsa.dot.gov. Second, check out one of your mover's marked fleet vehicles by looking for the US DOT number printed on the doors of the cab and again on the rear tractor.
While your moving company should be registered with the DOT in its home state, their DOT number should also be registered in any additional states they operate in. Therefore, make sure that your movers are registered in your home state, the state of your destination, and all states in between. In order to maintain their US DOT number, moving companies need to comply with all FMCSA safety regulations. This involves keeping detailed logs of all trips, attending safety training meetings, having vehicles inspected, and undergoing annual log audits.		Photo by Movers.com
As you can see, moving companies have to comply with strict standards in order to register, receive, and maintain a US DOT number. You should definitely make sure any mover you are thinking about using has a US DOT number.