The popstars will be performing on the second night of the music extravaganza, taking place on Sunday 6 December at London's 02 Arena.
Calvin was the first artist to be announced, and we're sure the world-renowned DJ will be giving fans a night to remember with a selection of his chart-topping dance hits.
And, fresh from his chart success with 'What Do You Mean?' and his latest single 'Sorry', we're sure Justin will be treating fans to new music and take us back in time to his earlier hits.
Joining the likes of Justin and Calvin will be Nick Jonas, Sigma and Charlie Puth. Pretty good line-up, right?!
The announcement follows on from confirmation yesterday that Ariana Grande and Nathan Sykes will be performing on the first night on Saturday 5 December.
Joining Ariana and Nathan will be the likes of Jess Glynne, David Guetta, Jason Derulo and Years & Years.
This sounds like a pop fest not to miss!
Tickets go on sale on Friday 6 November at 8am at capitalfm.com/jinglebellball.
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