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 A Fruitful Retirement: Social Security Benefit Taking your Social Security benefits at the right time may help maximize your benefit. How Women Can Prepare For Retirement Are women prepared for a 20-year retirement? A Look at Systematic Withdrawals This calculator may help you estimate how long funds may last given regular withdrawals.