It depends on your state's rules and how they interact with any adjacent states you may tow in. For example in my state WA the 26001 weight effects all vehicles whose GCVWR exceed 26K. However there are exceptions. If you fall under the exceptions you are ok; if not then you need a CDL.
Tow Vehicle rated weight plus trailer rated weight > 26K need CDL. If your combined rated weight is under 26K but you are stopped and weighed by the portables and are over 26K then you have a problem. Many rules are universal but there are exceptions that are unique to the states.
Here is my states flow diagram not applicable outside WA ---- check your own state.
The exceptions for us are: (your state will be likely similar, but still different, check the state website or better yet call them.)
By law, the following types of drivers don't need a commercial driver license (CDL):
Farmers transporting farm equipment, supplies, or products* to or from a farm in a farm vehicle are exempt if the vehicle is:
Operated by the farmer or a farm employee.
Not used in the operation of a common or contract motor carrier.
Used within 150 miles of the farm (in an air-mile radius).
If farmers meet all requirements of the farm exemption, they may operate farm-exempt vehicles between the states of Idaho and Oregon.
*Farm products include Christmas trees or wood products transported by vehicles weighing no more than 40,000 pounds licensed gross vehicle weight. This weight restriction applies only to Christmas trees and wood products.
Firefighters and law enforcement personnel are exempt when operating emergency equipment if they carry the certification card proving they have completed the Emergency Vehicle Accident Prevention Program (EVAP).
Recreational vehicle (RV) operators are exempt when driving an RV for non-commercial purposes. This exemption includes 2-axle rental trucks and horse trailers.
Military commercial drivers are exempt only when they are operating the proper military vehicle under a military license issued by their branch of the service.
Drivers of vehicles with air brakes that don't otherwise qualify as a commercial vehicle.