The ceremony will take place at the Belfast Odyssey Arena, Northern Ireland, on November 6.
Both Jessie J and Coldplay will perform along with LMFAO and already-announced band Red Hot Chili Peppers.
Jessie J, who is also nominated for an award at the show, spoke about her debut at the ceremony.
She said: 'I can't quite believe I'm nominated for three awards. It's like a dream, I keep pinching myself. And being nominated for Best UK/Ireland Act alongside artists like Adele, Coldplay, Kasabian and Florence is an honour.'