N.H. Rev. Stat. § 76:15
Inventories and tax lists already delivered to tax collectors shall be amended by selectmen or assessors to the extent of correcting errors or perfecting the description of certain property therein listed, upon application made to them by the tax collector prior to posting of the notice of a tax sale or tax lien in accordance with the provisions of RSA 80. Notice of such amendment to the inventory shall be sent by the selectmen or assessors, in writing and by registered mail, prior to the posting of the list of delinquent taxes by the tax collector but not more than 30 days prior to the posting, to the last known address of the owner or of the persons taxed.
RSA 76:15
1947, 111:1. RSA 76:15. 1969, 23:11. 1983, 135:2. 2010, 301:1, eff. Sept. 11, 2010.