N.H. Rev. Stat. Ann. § 490:18

The justices shall be entitled to receive their actual personal expenses when absent from the court in the performance of their official duties. A justice who resides more than 50 miles from the court may be reimbursed for money paid for office rent. The justices shall not be reimbursed for mileage to commute from the justice's residence to the court except for any mileage in excess of 50 miles each way. A temporary justice shall be entitled to receive the same expenses and reimbursements, except for office rent, for the period of such service.