Nightwish will unveil the identity of their new singer on May 30, the same day a new download only single will be released.
The track, 'Eva' is taken from the band's sixth studio album which is scheduled for release on September 26.
All proceeds from the single will go to an as-yet unnamed charity.
Nightwish fired their original singer, Tarja Turunen, via an "open letter," which was given to the singer immediately following their final concert together.
The show, which took place on October 21 2005 at the Hartwall arena in Helsinki, was filmed for the 'Ed of an Era' DVD.
The new vocalist has been chosen from around 2000 applicants.