The 53-year-old businessman is expecting his first son with socialite girlfriend Lauren Silverman but may not leave him his fortune as he believes it would be better spent on worthy causes, reported Contactmusic.
"I am going to leave my money to somebody. A charity, probably - kids and dogs. I don't believe in passing on from one generation to another," Cowell said.
"Your legacy has to be that hopefully you gave enough people an opportunity, so that they could do well, and you gave them your time, taught them what you know," he added.
"A lot of people who retire, they hate their job so much, they just love the idea of not working any more. That horrifies me. I'm going to be still working in my 80s or 90s," he said.