Where do I apply for a USDOT number or inactivate my USDOT? Click here to apply for a USDOT number (or inactivate). September 05, 2015 19:46 Related articles When do my IFTA license and decals expire? Do I need an IFTA license? Is a USDOT number required prior to registering for IRP? How do I qualify for an exemption of sales tax on industrial machinery purchased to fabricate the product I manufacture? I forgot my account number. What can I do?