N.H. Rev. Stat. § 80:52-a
Any town by vote at a town meeting under a proper article in the warrant or by vote of the board of selectmen or the town council and any city by vote of its governing board may authorize the prepayment of taxes and authorize the collector of taxes to accept payments in prepayment of taxes. If a town or city so votes, any person, firm or corporation owning taxable property may, at any time before notice of the amount of taxes assessed against said property has been received, make payments on account of such taxes as will be due and the collector shall receive such payments and give a receipt therefor and credit the amounts paid toward the amount of the taxes eventually assessed against said property. In any town or city which shall vote to authorize the prepayment of taxes the collector of taxes shall give such bond in the form and amount which the commissioner of revenue administration shall require, and the collector shall pay over all sums so received to the town treasurer under the provisions of RSA 41:35. No taxpayer shall be allowed to prepay taxes more than 2 years in advance of the due date of the taxes. No interest shall accrue to the taxpayer on any prepayment, nor shall any interest be paid to the taxpayer on any prepayment which is later subject to rebate or refund.
RSA 80:52-a
1963, 36:1. 1973, 544:8. 1989, 155:1. 1998, 244:1, eff. Aug. 24, 1998.