N.H. Rev. Stat. § 664:17
No political advertising shall be placed on or affixed to any public property including highway rights-of-way or private property without the owner's consent. All political advertising shall be removed by the candidate no later than the second Friday following the election unless the election is a primary and the advertising concerns a candidate who is a winner in the primary. Signs shall not be placed on or affixed to utility poles or highway signs. Political advertising may be placed within state-owned rights-of-way as long as the advertising does not obstruct the safe flow of traffic and the advertising is placed with the consent of the owner of the land over which the right-of-way passes. No person shall remove, deface, or knowingly destroy any political advertising which is placed on or affixed to public property or any private property except for removal by the owner of the property, persons authorized by the owner of the property, or a law enforcement officer removing improper advertising. Political advertising placed on or affixed to any public property may be removed by state, city, or town maintenance or law enforcement personnel. Political advertising removed prior to election day by state, city, or town maintenance or law enforcement personnel shall be kept until one week after the election at a place designated by the state, city, or town so that the candidate, or a member of the candidate's campaign or local political committee of the same party may retrieve the items.
RSA 664:17
1979, 436:1. 1994, 4:28. 2006, 273 : 1 . 2013, 24 : 1 , eff. July 15, 2013.