Social Security will pay benefits to those who have paid into the system, their beneficiaries in many cases, and also to some disabled individuals who have not paid into the system.

In general, Social Security Benefits will only be paid in cases where individuals paid into the system. The exception is Supplemental Security Income (SSI), which is actually paid from the general tax revenue of the government, and not the actual Social Security trust funds, though it is administered by the Social Security Administration.

SSI is paid to individuals who are impoverished and have need of income assistance due to disability or blindness. FICA payroll taxes are the source of Social Security Funds. 12.4% of employee compensation (with the maximum considered compensation being $118,500 in 2016) is paid into the system every year. There is a formula which calculates the size of the benefit that an individual will receive at Normal Retirement Age (NRA | 65-67).

In order to be eligible at all (excluding SSI) you must have earned at least $5,040 a year for at least 10 years. The $5,040 amount is the total of 4 “credits” of work, and it’s worth knowing that this credit system is part of Social Security benefits calculations.

Once you are eligible, your benefit will be calculated by taking your income (up to $118,500 in 2016) in the 35 highest-earning years and dividing it by 420 (which is the number of months in 35 years) and then that amount will go into the final calculation to determine your benefit at Normal Retirement Age (NRA | 65-67).

If you have not worked 35 years, they will include “0” years in the calculation. The average Social Security benefit paid to a married couple in 2016 is about $2,200 a month.

Social Security Disability eligibility depends on your age at the onset of the disability and various amounts of credits are required in different age bands to receive benefits. (SSD qualifications — found here)

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