N.C. Gen. Stat. § 20-86
Any person, firm or corporation engaged in the business of transporting persons or property for compensation, except as otherwise provided in this Article, shall, before engaging in such business, pay the license fees prescribed by this Article and secure the license plates provided for vehicles operated for hire. Any person, firm or corporation operating vehicles for hire without having paid the tax prescribed or using private plates on such vehicles shall be liable for an additional tax of twenty-five dollars ($25.00) for each vehicle in addition to the normal fees provided in this Article; provided, that when the vehicle subject to for-hire license has attached thereto a trailer or semitrailer, each unit in the combination, including the tractor, trailer and/or semitrailer, shall be subject to the additional tax as herein prescribed; provided, further that the additional tax herein provided shall not apply to trailers having a gross weight of 3,000 pounds or less.
N.C. Gen. Stat. § 20-86