Q. How to Deactivate a DOT Number
If you are no longer in business as an interstate motor carrier and would like to inactivate your DOT Number, you must file form MCS-150.
For more information, please see this FMCSA FAQ.
For further assistance, contact the Federal Motor Carrier Safety Administration (FMCSA) at 1-800-832-5660 or email FMCSA via the web form.