N.H. Rev. Stat. § 349:8
Every person, proprietorship, partnership or association registered in accordance with the requirements of this subdivision shall be required to reregister at the time of the expiration of the 5-year period set forth in RSA 349:6. The secretary of state shall, at least 6 months prior to the expiration of the term of registration, forward notice of the requirement of renewal together with a proper form for such renewal. A second such notice shall be mailed at least 30 days prior to expiration. Unless within 30 days after expiration said registration is renewed, the registration shall be discontinued and the name thereby abandoned and free. The secretary of state shall cancel from his register all registrations more than 5 years old and not renewed in accordance with the provisions of this section.
RSA 349:8
1955, 59:2; 284:1 par. 8. 1985, 339:14, eff. June 14, 1985.