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? Name Email Address Question Thank you! Oops! Related Contents Tuning Your Social Security Benefit When should you take your Social Security benefit? The Pre-Retirement Checklist This checklist can give you a quick snapshot of how prepared you are. Saving for Retirement This calculator can help you estimate how much you may need to save for retirement.