18 Years Worth of Days The average retirement lasts for 18 years. Are you prepared to fill that many days? 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. The History of Retirement Do you know where the idea of “retirement” comes from? Investment Strategies for Retirement Investment tools and strategies that can enable you to pursue your retirement goals.