Social Security disability benefits are available to people who, because of physical or mental conditions, are unable to work. In order to decide which disability applicants ("claimants") are able to work and which aren't, the Social Security Administration (SSA) will review medical records to determine what functional limitations the claimant has.
Functional limitations are any limits on activities that you have difficulty doing because of a medically documented illness or injury (as opposed to activities that you don't enjoy or don't know how to do). Functional limitations cover a wide array of physical and mental tasks that are important to complete your daily routine or work full-time.
Social Security is interested in the impact your functional limitations have on your ability to work. At almost every step of the agency's sequential evaluation process for evaluating disability claims, a claims examiner will look closely at your doctor's notes and your function report in order to decide to what extent your medical condition limits your activities.
The SSA will assess your functional limitations to determine the following:
Functional limitations are especially important in determining what, if any, kind of work you can do. The SSA will take your functional limitations and translate them into terms an employer would understand in a process called assessing your residual functional capacity (RFC).
Social Security doesn't expect you to be able to work at a job that's outside of your capabilities, mentally or physically. Your RFC reflects the functional limitations you have with your activities of daily living because it makes sense that anything you struggle with at home (such as standing long enough to vacuum or mop) would be difficult to do at work.
If you have any functional limitations from a physical condition, your RFC will almost certainly restrict you to a certain exertional level. Exertional levels are defined by how much weight you can lift and how long you can stand and walk. For example, if you can't walk longer than 15 minutes as a result of knee surgery, your RFC will have a restriction to sedentary (sit-down) work. If you have a mental condition, your RFC will restrict you to semi-skilled or unskilled jobs.
Restrictions in your RFC that aren't about how much weight you can lift or how long you can be on your feet—but still affect the types of jobs you can perform—are called non-exertional limitations. Non-exertional limitations include the following:
The RFC describes non-exertional limitations by the amount of time that you can perform the activities in a workday. How often you can perform a particular action depends on the severity of the condition causing the limitation. For example, if your arthritis causes daily, intense swelling in your hands, your RFC might restrict you to "occasional" manipulation of the hands and fingers. But if your arthritis causes only a slight tingling in your fingers, your RFC might restrict you to "frequent" manipulation.
Most disability claimants have an RFC that contains both exertional and non-exertional limitations. Because Social Security is required to consider the combined impact of all of your functional limitations, the more you have, the better your chance that the SSA will approve your disability claim.
Social Security needs to see that your RFC not only rules out any of the jobs you've done in the past, but also prevents you from performing any other jobs in the national economy. The agency uses a tool called the Dictionary of Occupational Titles (DOT) to categorize all jobs according to their physical and mental demands.
A claims examiner will classify your past work by looking at the DOT description of the job duties. The examiner will then compare the limitations in your RFC with the exertional and non-exertional requirements of your past job to see if you could perform your past work.
If you can't do your past job duties with your current RFC, the examiner will ask a vocational analyst to determine if there are any other jobs you could do.
Learn more in general about how your RFC can qualify you for a medical-vocational allowance.
Because establishing functional limitations is such an important part of a disability claim, Social Security will be on the lookout for any doctor's opinions that can help the agency determine the scope of your limitations. If you have a supportive medical source statement from one or more of your doctors, you'll have an easier time qualifying for disability.
The best medical source statements are ones written by providers who treat you in their area of expertise and point to the diagnostic criteria they used to arrive at their opinion on your limitations. Keep this in mind when deciding which providers you'll ask to complete an RFC form. For example, a statement from the psychologist who you regularly meet for counseling is more persuasive than a statement from a family doctor who you saw once for anxiety.
Consider getting help from a disability attorney or advocate. A disability lawyer will determine which of your doctors is in a better position to provide an opinion about your conditions and can work directly with your treating doctor to document your functional limitations properly. For more information, see our article on how disability attorneys document your limitations.
Updated September 9, 2022