N.H. Rev. Stat. Ann. § 455:14

Such commissioner of deeds may, both within and without this state, administer oaths, take depositions and affidavits to be used in this state and notify parties of the time and place thereof, and take the acknowledgment of deeds or instruments to be used or recorded in this state, in the same manner and with the same effect as a justice of the peace of this state may do within the state.