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 Tuning Your Social Security Benefit When should you take your Social Security benefit? When Should You Take Social Security Monthly Social Security payments differ substantially depending on when you start receiving benefits. Investment Strategies for Retirement Investment tools and strategies that can enable you to pursue your retirement goals.