N.H. Rev. Stat. § 266-A:24
Each motor carrier holding a certificate or a permit under the provisions of this chapter shall annually apply to the department of safety, division of motor vehicles, on blanks to be furnished by it, for the registration of each vehicle, operated under the provisions of such certificate or permit and pay to said department fees as provided for in RSA 266-A:25. Upon receipt of such application and fee, a distinguishing number plate or plates and registration certificate shall be furnished by the division for each vehicle applied for and said plates shall be prominently displayed on the vehicle in such manner as the director of the division shall prescribe. No such plates shall be transferred from one vehicle to another, except upon authority and with the consent of the department of safety, and the payment of the fees prescribed in RSA 266-A:25. Registration certificates and number plates issued under the provisions of this section shall be used coincidental with, and shall expire with, the corresponding registration certificate and number plates issued by the division of motor vehicles, department of safety, of this state under the provisions of RSA title XXI; provided, however, that if the vehicle so registered as a motor carrier is not registered with the division of motor vehicles, department of safety of this state under title XXI, said carrier registration certificate and number plates shall expire on March 31 next following the date of issue.
RSA 266-A:24
1941, 224:24. RL 304:24. RSA 376:24. 1961, 166:16. 1985, 402:6, I(e)(7). 1988, 288:25, eff. Jan. 1, 1989.