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? Address Thank you! Oops! Related Contents A Fruitful Retirement: Social Security Benefit Taking your Social Security benefits at the right time may help maximize your benefit. Does Your Portfolio Fit Your Retirement Lifestyle? Lifestyle considerations in creating your retirement portfolio. Women and Retirement Women must be ready to spend, on average, more years in retirement than men.