The lads are planning a TV special called You're The One for later this year. They've opened a phone line for singers to apply for the role.
Auditions will be held in London and Manchester on 24 and 25 August, with the boys in the hotseat as judges.
The album will be out later this year. Details are on the Westlife website.
The winner will perform with the lads on TV, as well as recording a track for the album.
Amazing
Nicky said: "We really can't wait to meet somebody with an amazing voice and we'll know You're The One!"
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