N.H. Rev. Stat. Ann. § 655:14-a

Every candidate for state or federal office who intends to have his name placed on the ballot for the state general election by means other than nomination by party primary shall file a declaration of intent with the secretary of state as provided in RSA 655:17-a or RSA 655:17-b during the same time period in which party candidates file a declaration under RSA 655:14.