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? Volunteering in Retirement For many, retirement includes contributing their time and talents to an organization in need. Roth 401(k) vs. Traditional 401(k) This calculator compares employee contributions to a Roth 401(k) and a traditional 401(k).