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 The Power of Tax-Deferred Growth Why are 401(k) plans, annuities, and IRAs so popular? 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.