N.H. Rev. Stat. Ann. § 21-G:6-a

Notwithstanding any other provision of law to the contrary, the head of any state agency or department and any authorized employee or agent of the head, may accept credit cards or debit cards for the online payment of any of the taxes, penalties, interest, or fees administered by such commissioner or collected by the department. The amount of any service charge collected shall be disclosed in advance of the transaction to the individual paying the tax, penalty, or fee and shall be at a reasonable and customary rate approved in advance by the comptroller.