> who knows when I'll die? That, you can insure against by buying a lifetime pension. Quick math: say that you retire at 65 and expected life expectancy is 85

> who knows when I'll die? That, you can insure against by buying a lifetime pension. Quick math: say that you retire at 65 and expected life expectancy is 85. Then, you’ll need 240 months of retirement money, and an insurer will probably pay you around 1/200th or so [1] of what you pay them when you’re 65 each month for as long as you live (they can pay you a bit more than what you pay them and still make a profit because they get your money, on average, 10 years before they have to pay you) That’s costly if you happen to die young but a good deal if you happen to live long, but moves the risk of you running out of money to a third party. The more difficult questions are how healthy you’ll be and what inflation will be after you retire. If you happen/manage (that’s partly under your control) to stay fit and healthy, you’ll probably spend more on activities and hobbies after you retire. If you happen to get a chronic disease, but still live long, you’ll have to spend more on healthcare. [1] depending on whether you want your partner to still receive a pension after you die, how much investment risk you’re willing to run, etc.