N.H. Rev. Stat. § 259:23
"Domicile" shall mean a natural person taking up residence in a town or city within the state and includes but is not limited to occupying a primary place of habitation, placing children in a public school within the state, accepting gainful employment, or being a registered voter liable for a resident tax, provided, however, that no person shall be considered to be domiciled in this state who simultaneously claims residence in any other state for any of the purposes indicated above. In the case of other than a natural person, domicile shall also apply in the case of vehicles principally garaged or kept on the premises of a firm or corporation with a place of business within the state.
RSA 259:23
RSA 259:1, XXXVII. 1979, 135:4. 1981, 146:1, eff. Jan. 1, 1982.