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. Eight Mistakes That Can Upend Your Retirement There are common mistakes you can avoid when saving for retirement. Retirement Plan Distributions There are a number of ways to withdraw money from a qualified retirement plan.