The TV star - who has been a fixture on This Morning for 15 years - will present a new programme in the New Year, according to GB News.
Holmes said: “I’ve spent my career on broadcasting firsts and start-ups, and GB News is one of the most exciting yet.
“It’s just the kind of shake-up the industry needs.”
Broadcaster and journalist Eamonn Holmes joins GB News. pic.twitter.com/Mr7gO7qNF9
— GB News (@GBNEWS) December 10, 2021
The star added: “I’ve admired GB News from the beginning for its clever mix of punchy debate but delivered with warmth and even some fun.
“To me the greatest honour in journalism is to give a voice and respect to the unheard, and that’s exactly what GB News is all about.”
Holmes, 62, is known for hosting This Morning with his wife Ruth Langsford.
However, in January this year Alison Hammond and Dermot O'Leary replaced the pair, meaning the husband and wife team then only hosted the ITV show during key holidays.
It isn't known whether Langsford - who is also a regular on Loose Women - will remain on the programme.
GB News launched in June but has had a few problems.
The channel came under fire for technical glitches when it started and it was also victim to a few pranks, with comedian Adam Pacitti calling in and mooning live on air and presenters tricked into appearing to say some rude words.
Then in September broadcasting veteran Andrew Neil stepped down as chairman.
Additional reporting by PA.
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