18 Years Worth of Days The average retirement lasts for 18 years. Are you prepared to fill that many days? Share | Related Content A Fruitful Retirement: Social Security Benefit Taking your Social Security benefits at the right time may help maximize your benefit. 9 Facts About Retirement Regardless of how you approach retirement, there are some things about it that might surprise you. Retirement Plan Distributions There are a number of ways to withdraw money from a qualified retirement plan.