http://www.wildlife.state.nh.us/Fishing/fishing_buy_a_license.htm
There are three ways to purchase a N.H. fishing license: online, by mail or in person at one of Fish and Game's license agents.
Remember to go out and get your new License for the start of the new season. The license is good from April-March, so your current one is almost ready to expire.
You can by license online at-
https://onlinesales.wildlife.state.nm.us/