It was claimed last month that the 51-year-old had been given a second run of The Jonathan Ross Show, but The Sun now reports that the agreement extends to a third series of the programme.
"It was always a gamble for him to reprise his chatshow on another channel," a source said. "He had been synonymous with Friday nights on the BBC, but was replaced by Graham Norton in that slot.
"But he has brought in great guests for ITV and his ratings have been good so it was a no-brainer that he should sign up again."
Ross defected to ITV from the BBC back in July 2010.
He previously defended the multi-million pound salary he received at the corporation, stating: "Sure I was paid a lot of money, but I'm not in a regular job. I'm in showbusiness and I was at the top of my game."
Watch Jonathan Ross interviewing Alan Partridge on his ITV1 chatshow below (Video contains strong language and adult humour):