18 Years Worth of Days The average retirement lasts for 18 years. Are you prepared to fill that many days? Share | Related Content Women and Retirement Women must be ready to spend, on average, more years in retirement than men. Money that Buys Good Health is Never Ill Spent It's important to make sure your retirement strategy anticipates health-care expenses. Retirement Plan Distributions There are a number of ways to withdraw money from a qualified retirement plan.