Outside is retained by Simon Cowell's record label, Syco. It held a similar brief - which also includes promoting the associated DVD and tour - for the 2004 series, taking on winner Steve Brookstein, who flopped.
Neil Reading continues to promote last year's winner, Shayne Ward, seen as having potential career longevity.
PR for the show itself, whose current third series will climax before Christmas, is handled by Sara Lee, a publicist at Talkback Thames, and ITV publicist Ben Webster.
Outside has also been taken on by P Diddy for UK PR. The account is led by account director Annabel Fox, who joined last week from Halpern, where she was celeb deputy director. She has been replaced by Tom Macklin of celebrity specialist agency Upfront TV.
Separately, it has emerged that Outside's head of music corporate Jonathan Morrish is now working part-time.