While it may seem arbitrary, the law says that Social Security Disability Insurance (SSDI) can be paid only after you have been disabled continuously throughout a period of five full calendar months. SSDI benefits begin with the sixth full month after the date when you were unable to work due to your disability as established by the Social Security Administration. This is called the “onset date”. You will not be paid any disability benefits for any month during the waiting period.
Supplemental Security Income (SSI) recipients are not subject to the five-month waiting period. They are paid Social Security disability benefits starting from the onset date. Since all disability applicants are required to be disabled or expected to be disabled for at least 12 months to qualify for disability payments, your onset date serves as the starting point of this 12-month period.