18 Years’ Worth of Days The average retirement lasts for 18 years, with many lasting even longer. Will you fill your post-retirement days with purpose? Share | Related Content Should You Ever Retire? A growing number of Americans are pushing back the age at which they plan to retire. Or deciding not to retire at all. Social Security: The Elephant in the Room Some people wonder if Social Security will remain financially sound enough to pay the benefits they are owed. Self-Employed Retirement Plans Estimate the maximum contribution amount for a Self-Employed 401(k), SIMPLE IRA, or SEP.