You can’t predict financial emergencies — but you can prepare for them. To do that, you can build an emergency fund to pay for unexpected expenses, some of which may be sizable. Without one, you might be forced to dip into your investments, possibly including your retirement accounts, such as your IRA or 401(k). If this happens, you might have to pay taxes and penalties, and you’d be withdrawing dollars that could otherwise be growing over time to help pay for your retirement.