The group - Josh Cuthbert, JJ Hamblett, Jaymi Hensley and George Shelley - finished fourth in the competition last year.
The group have since signed to RCA records and will be releasing their debut single in June.
In a cliche filled press statement, the boys said this week: “We are absolutely thrilled to be signed to RCA. Being on X Factor was such a great experience and the perfect way for us to start our musical journey.
"Hopefully 2013 will an amazing year for us and we cannot wait for everyone to hear our music.”
There's plenty of competition around for the group right now, including former X Factor stars One Direction.
But a confident Union J declared in this week's Top of the Pops magazine: "We have better songs.”
District3 haven't been officially signed yet, and Union J aren't too worried about them.
George said: “It’s not just D3 we need to compete with – there’s The Wanted, Lawson, 1D and JLS!”
Both groups are currently on tour, which moves to Cardiff tomorrow.