Social Security Disability Insurance (SSDI) is a program that pays benefits to those who become disabled before they reach the age of retirement and are unable to work.
Work Credits: In order to be eligible for Social Security Disability benefits, you need to have earned a set number of work credits. Work credits are earned every year that you work and you may earn up to four credits per year. The number of work credits that you need to qualify for benefits depends on your age at the time you became disabled.
Medical Condition: In addition to fulfilling the number of work credits, you must have a medical condition that meets the Social Security Administration's (SSA) definition of a disability. Those who fulfill the medical condition requirement are those with a severe, long-term, total disability. "Severe" means that the extent of your condition interferes with your ability to perform basic work-related tasks. "Long-term" means that your condition has lasted, or is expected to last, for at least one year. "Total disability" means that you are not able to perform "substantial gainful activity" (SGA). Meaning, if you are unable to gain an income of $1,040 per month, the SSA will find that you are not able to perform SGA.
Approval: If the SSA approves you for disability benefits, you will not receive those benefits for five months. This means that if your claim is approved right away, you will start to receive benefits five months from the date of approval. Most claims take months to a year for approval, and when this happens, you will be credited disability backpay. Disability payments start on the sixth month after your disability began.
Denial: Most Social Security Disability claims are initially denied. When this happens, an appeal of the decision may be made. Within 60 days of your receipt of the letter, request a review of the denial. To appeal the decision, the first level of appeal is the Request for Reconsideration, which is simply a request to have another claims examiner review your case. If you are subsequently denied, you may request a hearing with an SSA administrative law judge.
Benefits: In most cases, the claimant will receive "back pay". The amount of "back pay" recoverable depends on 3 Factors of Social Security Disability Back Pay.
In addition, with respect to benefits, see also, Differences Between Social Security Disability and Supplemental Security Income.