N.H. Rev. Stat. Ann. § 159:6-d

The director of the division of state police shall negotiate and enter into reciprocal agreements with other jurisdictions to recognize in those jurisdictions the validity of the license issued under RSA 159:6. The director shall apply to every jurisdiction with which New Hampshire does not have a reciprocity agreement, at least once every 5 years to obtain recognition in those jurisdictions of the license issued under RSA 159:6. Any such agreement executed shall not expire unless an expiration date is required under the statutes of the reciprocal jurisdiction.