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. How Will Working Affect Social Security Benefits? Knowing the rules may help you decide when to start benefits. Investment Strategies for Retirement Investment tools and strategies that can enable you to pursue your retirement goals.