The singer, who became an international star after wowing the judges on Britain's Got Talent, told fans to "watch this space" for more announcements.
She said: "There are plans in operation for that, but that's for later on."
Boyle was speaking at a central London press conference to announce the release of her Christmas single - a duet of O Come, All Ye Faithful with Elvis Presley.
All royalties from the song will go to Save The Children.
The singer, who has become an ambassador for the charity, filmed the video for the track at a St Rose of Lima Primary in Glasgow.
Boyle, who described it as "awe-inspiring" to sing with one of her childhood heroes, said: "Duetting with Elvis was beyond my wildest dreams. And now that this is able to raise money and help children is simply fantastic."