The TV star will start filming the auditions for Britain’s Got Talent in January and will be back hosting the live shows alongside Declan Donnelly later in the year.
Ant, 43, is also expected to be back in Australia next year to return to his co-hosting job on I’m A Celebrity Get Me Out of Here, which has been filled by Holly Willoughby this year.
Ant and Dec’s comeback as a double act comes after McPartlin took eight months off work after crashing his car in a drink drive incident.
A source close to the star said: “Ant has completed his recovery and ITV has decided he is ready to be back at work for Britain’s Got Talent filming, which starts next month.
“It’s been an incredible difficult two-year period but he has been entirely focused on turning his life around in order to return to work.
"ITV is very excited about Ant and Dec being reunited – but Ant’s recovery has been everyone’s first priority.”
Ant’s troubles - which included a battle with drug addition - forced him to miss the live Britain’s Got Talent episodes last year and also the entire series of I’m A Celebrity, which saw This Morning host and close friend Willoughby step in.
Next year’s series of Saturday Night Takeaway, which requires lots of filming before the series starts on air, has also been cancelled in order to allow Ant more time for his recovery.
Ant was spotted smiling while walking his beloved dog Hurley in West London hours before Dec and Holly hosts the I’m A Celeb final.
He has split from wife Lisa Armstrong and found love again with Anne-Marie Corbett, his former assistant.