A host of celebrities from the showbiz and music worlds have been tipped to take over from the 50-year-old, with DJ Howard Stern, actor Jamie Foxx and even Noel Gallagher in contention for the role.
However, Cowell has told People that there are certain prerequisites for potential candidates.
"You have to be good looking," he said. "Secondly, you have to know what you're talking about. I'm starting to realise with these shows that you have to put people on that actually know what they're talking about.
"Rather than guessing, they really have to have experience, so that you cannot just criticise - you can offer constructive advice as well."
Cowell insisted that his successor must also have knowledge of the music industry itself, saying: "I think it's really important. When we first started we had a record producer, an artist and an A&R man. So you’ve covered pretty much everything. I would say someone who has had managerial experience is always helpful. But in simplistic terms if you're going to give a score you generally need to know what you’re talking about.
"I think over the years judges have been replaced by personalities. That in the long term will create problems because you’ve got to be able to spot a star. So whoever replaces me, my advice has always been [to] find somebody who actually knows what they're talking about."
> Click here to read DS's interview with Simon Cowell