N.H. Rev. Stat. Ann. § 236:72-a

For any new official business directional signs authorized after July 14, 1987, and beginning April 1, 1988, for all official business directional signs authorized by the commissioner to serve privately owned businesses, an annual permit fee of $10 shall be collected by the commissioner. Permits shall expire on April 1 following the date of issue or renewal and fees shall not be pro-rated. All fees collected under this section shall be deposited in the highway fund.