N.D. Cent. Code § 43-19.1-22
A certificate of registration expires on December thirty-first of the year of issuance if registration is on an annual basis and of the year after issuance if issued on a biennial basis and becomes invalid after that date unless renewed. The executive director for the board shall notify every registrant under this chapter of the date of the expiration of the registrant's certificate of registration and the amount of fee required for its renewal. The notice must be mailed or electronically sent, if the registrant has opted in to receive electronic renewal notices, to the registrant at the registrant's last-known address or electronic mail address at least one month in advance of the expiration of the registrant's certificate. Renewal may be effected at any time before or during the month of December by the payment of a fee as established by the board, not to exceed the fees established in section 43-19.1-18. Renewal of an expired certificate may be effected under rules adopted by the board regarding requirements for re-examination and penalty fees.
N.D.C.C. § 43-19.1-22