I'm in my early 30s so I still have a fair time left in life (god willing). So I would honestly have to say around the 10 mil mark to be able to retire comfortably. This sounds like a lot but this also includes funds for future children's education and healthy upbringing. This also includes enough for me to pay off my house and upgrade to a larger long term residence. Along with funds to invest so that my money will be working and not just completely sit in a long term deposit bank account.