Niconico Points will expire after a certain period of time
Your unused points (either purchased or gifted) will expire and can no longer be used after the expiration date.
When Will My Points Expire?
Points earned (purchased or gifted) between Oct.1st to September 30 of the following year, the points will expire on September 30 another year after.
For example,
[Date of acquisition]
Points purchased/earned between 01/10/2017 to 30/09/2018
[Expiration date]
30/09/2019