In order to be eligible to receive Social Security benefits – retirement, disability, or survivor benefits – a worker must earn eligibility to receive the benefits. The general rule of thumb is that for full benefits, the worker must earn at least 40 quarters of credit within the system.
Social Security Credit
Generally speaking, a quarter of Social Security credit is earned for each $1,120 earned (in 2010). This amount is indexed each year – for example, the amount of earnings for a credit in 2009 was $1,090. So if a worker earns at least $4,480 in 2010, four quarters of credit are earned with the Social Security system.
If you become disabled before age 62, disability benefits may be available to you if you have at least six quarters of credits earned. Of course, these benefits will be reduced from the maximum, based upon how many credits you happen to have earned.