Retirement refers to the time of life when one chooses to permanently leave the workforce behind. The traditional retirement age is 67 in the United States and most other developed countries, many of which have some kind of national pension or benefits system in place to supplement retirees’ incomes. The full retirement age is 66 if you were born from 1943 to 1954. The full retirement age increases gradually if you were born from 1955 to 1960 until it reaches 67. For anyone born 1960 or later, full retirement benefits are payable at age 67. In the U.S., for example, the Social Security Administration (SSA) has been offering retirees monthly Social Security income benefits since 1935.