The 37-year-old has only released one album since her 2013 victory but insists she is grateful for her time at 55-year-old Simon's label Syco.
She told The Sun: "I'm really grateful for everything X Factor has done for me. I'm going straight into a studio to write after the tour.
"I would also maybe like to get into acting and I would love to do Strictly Come Dancing. I'm happy I got my house extension – that's what I entered the competition for."
A spokesperson confirmed: "Sam Bailey is no longer with Syco," while a source added: "Music is a tough business. Simon realises most X Factor winners have a short shelf life."
Taking to Twitter today to discuss the news, Sam wrote: "Hi guys yes it's true I have parted ways with syco!! Don't worry tho, I'm happy xx lots of exciting things happening xx [sic]"
The sacking wouldn't have come as a total shock to mum-of-three Sam. In December she admitted she had no idea what would happen when her contract was up.
Speaking to the Mirror at the time, Sam said: "There's a cooling-off period and then there are negotiations, so we'll see. I could be unemployed tomorrow.
"There are other things I could be doing. I am getting a lot of interest in all sorts of directions."
Sam's debut album The Power Of Love, a mix of covers and original tracks, was one of the fastest-selling albums last year.