Someone has a trailer used to haul supplies.  How does the owner determine if a UT or TR tag is needed?
The definition of a utility trailer is that it is designed to be pulled behind an automobile or "pickup truck".  A "pickup truck" is defined in Section 32-6-62 as a truck with not  more than two (2) axles and a gross weight not exceeding 12,000 pounds.  Thus, if the weight of a truck plus trailer plus heaviest load does not  exceed 12,000 pounds, a UT tag is needed:  otherwise a TR ($20.00) plate is required.

What is a "fleet trailer" tag (TM)?
A "TM" license plate is a five (5) year rental trailer tag.  Fees are paid annually.  A U-Haul company is the major registrant.

What are the qualifications for a five (5) year trailer/semitrailer tag?
A registrant must own at least 50 trailers or semitrailers and all must be registered in the same county.  See Departmental Regulation 810-5-1-481 for additional information.

Is a horse trailer required to be registered?
Section 40-12-252 exempts "any trailer or semitrailer used by a farmer exclusively for transporting farm products to and from market or for transporting the personal property of the farmer for his own use on the farm."  The term "farmer" would include one raising horses, but, not one who happens to own horses.