Before a worker can file for Social Security Disability Insurance (SSDI), they must usually receive short-term disability benefits for a certain period of time. Once these benefits end, people are then eligible to apply for SSDI. If approved, injured people will receive a portion of their previous income each month until they are able to return to work. The number of work credits earned determines whether a person could receive SSDI. All workers may earn a maximum of four work credits each year. The number of credits needed to qualify for benefits varies by age, but typically, the Social Security Administration (SSA) will not pay benefits to individuals with an insufficient number of work credits.