Tenn. Code Ann. § 55-4-207: Expiration and renewal

(a) Notwithstanding § 55-4-104 or other provisions of part 1 of this chapter, all license plates issued under this part and certificates of registration shall not expire on March 31 of each year, but rather shall expire pursuant to subsection (b).

(b) With respect to motor vehicles using plates issued pursuant to this part, the commissioner shall establish a system of registration renewals at alternate intervals which will allow for the distribution of the registration workload as uniformly as is practicable throughout the calendar year. Registrations issued under the alternate method are valid for twelve (12) months, and expire on the last day of the last month of the registration period. However, during a transition period, or at any time thereafter when the commissioner shall determine that the volume of work for any given interval is unduly burdensome or costly, either registrations or renewals, or both of them, may be issued for terms of not less than six (6) months nor more than eighteen (18) months. The fee imposed for registration of any vehicle under the alternate interval method for a period of other than twelve (12) months shall be proportionate to the annual fee fixed for the vehicle and modified in no other manner, except that the proportional fee shall be rounded off to the nearest quarter of a dollar ($0.25).

(c) Notwithstanding this section, dealer plates shall be issued and renewed pursuant to § 55-4-226 .