18 Years Worth of Days The average retirement lasts for 18 years. Are you prepared to fill that many days? Share | Have A Question About This Topic? Address Thank you! Oops! Related Contents Social Security: By the Numbers Here are five facts about Social Security that might surprise you. Where Will Your Retirement Money Come From? Retirement income may come from a variety of sources. Here's an overview of the six main sources. Retirement Plan Distributions There are a number of ways to withdraw money from a qualified retirement plan.