The reformed boyband will play a 45-minute set at the Midlands Music Festival in Tamworth Castle Grounds on August 8.
Further acts confirmed include Lemar, JLS, Eoghan Quigg, Liz McLarnon and The Automatic.
Former X Factor contestants Andy Abraham, Chico, Laura White, Austin Drage and Rachel Hylton will also perform at the event.
The festival has been organised to support premature baby charity Just 1 Life and will raise vital funds for neo-natal units across the country.
Tickets start at £45 and are available from May 16.