Social Security Disability (SSDI)
You may receive SSDI benefits if you are under your full retirement age and have:
The requisite amount of current Social Security disability work credits, and
A severe medical impairment or impairments (physical and/or mental) that are expected to prevent you from performing "substantial" work for one year or more or have a condition that is expected to result in death.
If you do not have enough work credits to qualify for SSDI benefits, you may be eligible for these benefits based on the work credits of a prior spouse or parent.
Supplemental Security Income (SSI)
SSI is a federal supplemental income program funded by general tax revenues, not Social Security taxes. It helps aged, blind, and disabled individuals who have limited income and resources by providing monthly cash payments to meet basic needs for food, clothing, and shelter. This program may be appropriate if you have insufficient work credits to qualify for SSDI benefits, your work credits have “expired,” or you have not worked in the past.
Benefits based on your record (when you die) can be paid to your:
Widow/widower aged 60 or older, 50 or older if disabled, or any age if caring for your child who is under age 16, or who was disabled before age 22.
Children, if they are unmarried and under age 18, under 19 but still in school full time, or 18 or older but disabled before age 22.
Parents, if you provided at least one-half of their support.