N.H. Rev. Stat. § 541:18
No appeal or other proceedings taken from an order of the commission shall suspend the operation of such order; provided, that the supreme court may order a suspension of such order pending the determination of such appeal or other proceeding whenever, in the opinion of the court, justice may require such suspension; but no order of the public utilities commission providing for a reduction of rates, fares, or charges or denying a petition for an increase therein shall be suspended except upon conditions to be imposed by the court providing a means for securing the prompt repayment of all excess rates, fares, and charges over and above the rates, fares, and charges which shall be finally determined to be reasonable and just.
RSA 541:18
1913, 145:18. PL 239 :18. 1937, 107:31; 133:92. RL 414:20. 1951, 203:16, eff. Sept. 1, 1951.