What Is an Annuity?
An annuity is a contract between you and an insurance company. You hand over a lump sum (or a series of premiums) and the insurer promises to pay you income later — either over a fixed period or for the rest of your life. That's it. The structure looks like life insurance in reverse: instead of protecting against dying too soon, an annuity protects against living too long and running out of money.
Annuities come in two broad flavors. Immediate annuities start paying within 30 days of purchase. Deferred annuities grow tax-deferred for years or decades before converting into income. Most retirees hold deferred annuities while they build a nest egg, then annuitize (turn on the income stream) when they're ready.