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How Is Disability Defined?

Both SSDI and SSI define disability as the inability to engage in any substantial gainful activity (SGA) because of a medically determinable physical or mental impairment(s):

  • That can be expected result in death, or
  • That lasted or, that we can expect to last for a continuous period of not less than 12 months.

We evaluate the work activity of persons claiming or receiving disability benefits under SSDI, and/or claiming benefits because of a disability under SSI. Under both programs, we use earning guidelines to evaluate your work activity to determine whether the work activity is SGA and whether we may consider you disabled under the law. While this is only one of the tests used to determine disability, it is a critical threshold in disability evaluation.

If your impairment is other than blindness, effective July 1999, earnings averaging over $700 a month generally demonstrate SGA. If you are blind, effective January 1999, earnings averaging over $1110 a month generally demonstrate SGA. (Any changes since this printing will be posted on the SSA web site.)

For SSDI, we use SGA as a factor to decide if you have a disability when you apply to get benefits. We also use SGA as a factor to decide if your disability continues when you are already receiving benefits.

For SSI, we use SGA as a factor to decide if you have a disability when you apply based on a condition other than blindness. (SGA is not a factor for SSI applicants who are blind.) We use the same SGA level under SSI for applicants with impairments other than blindness as we do in SSDI.

For SSI, we do NOT use SGA as a factor to decide if your disability continues when you are already on the rolls. Your SSI eligibility continues until you recover medically or we end your eligibility for a nondisability-related reason.