The amount of money someone needs to earn and put away for retirement at 55 depends on the sort of lifestyle that they want when they retire. Generally, people need about 70 to 80 percent of their pre-retirement income to live a similar sort of lifestyle, according to Time magazine.
Assuming average social security benefits and inflation, people retiring at 55 need 18 times their current annual income to have 75 percent of that amount for each year of retirement. This means that someone earning $100,000 a year would need $1.8 million saved to retire at 55. If that person continued working until the age of 65, they would need $1.2 million to retire comfortably.