Borderline intellectual functioning is a cognitive impairment that applies to people who have lower than average intelligence but do not have what Social Security calls “intellectual disorder” (a severe intellectual disability, formerly known as mental retardation). People with borderline intellectual functioning typically have difficulties with learning, reasoning, planning, abstract thinking, and judgment. Lower than average intellectual functioning can be caused by birth injury, infections, genetics, fetal alcohol syndrome, or environmental exposure to toxins such as lead.
Borderline intellectual functioning is diagnosed by IQ test scores that are between 71 and 84. While Social Security’s impairment listing for intellectual disorder (listing 12.05) requires an IQ of 70 or less, Social Security introduced a new listing in 2017 that covers borderline intellectual functioning. The new listing is for “neurodevelopmental disorders,” which generally means disorders that an individual has had since childhood. (Cognitive problems that develop in adulthood, such as dementia or difficulties after traumatic brain injury, are evaluated under the listing for neurocognitive disorders instead.)
The listing that applies to borderline intellectual functioning requires that the applicant have significant difficulties learning and using academic skills. The applicant must be able to show that he or she either is extremely limited in one of the following areas or "markedly" (severely) limited in two of the following areas:
Generally an extreme limitation in learning and understanding applies only to those with an IQ of 70 below. But many applicants will be able to show that their borderline intellectual functioning causes a marked limitation in learning and understanding. It may be more difficult for some applicants to show a severe limitation in a second area (social, concentration, or managing oneself), although it’s not uncommon for individuals with borderline intellectual functioning to have moderate limitations in these areas. (Note that this listing is the same for children with borderline intellectual functioning.)
If you don’t meet the listing because you only have a severe limitation in the area of understanding and using information, you could still win benefits by proving that your impairments make it impossible to find full-time work. This is generally only true, however, for applicants with borderline intellectual functioning in combination with physical or other mental impairments.
When an applicant fails to meet a listing, Social Security will assess the applicant’s mental and physical limitations to come up with the applicant’s mental "residual functional capacity,” or “mental RFC,” and a physical RFC. The RFCs are then used to determine whether there are any jobs the applicant can do despite his or her limitations.
A mental RFC will discuss the applicant's abilities in the following areas:
Following instructions. Applicants with borderline intellectual functioning may have a limited ability to understand, remember, and carry out complex instructions. They may require that tasks be broken into individual steps that can be completed one at a time, rather than being given a series of instructions that must be remembered and followed one after another.
Supervision and training. The need for close supervision and/or an extended training period is another, related limitation. A person with borderline intellectual functioning may not be able to do any of the jobs that don't provide much support from supervisors.
Concentration. People with borderline intellectual functioning may also have limited ability to concentrate and focus. They may need to avoid multitasking, or doing several things at once. As a result, they may be limited to jobs that involve only simple, routine tasks. Evidence of difficulties with concentration may be found in work evaluations that show frequent errors.
"Pace" is another workplace limitation that may apply to someone with borderline intellectual functioning. Someone who needs extra time to perform tasks may not be able to do certain jobs, such as assembly-line work.
Judgment. Because people with borderline intellectual functioning often have impaired judgment and reasoning ability, they may have a limited ability to make judgments on complex work-related decisions. This is another potential workplace limitation that should be included in the applicant's mental RFC, if applicable.
Social functioning. Borderline intellectual functioning often causes difficulties with social functioning and communication. Someone with this condition may be unsuited to jobs that involve dealing with customers. This should be reflected in the mental RFC as a limitation in contact with the general public.
A physical RFC will discuss the level of work an applicant can do:
After completing your mental and physical RFCs, Social Security will determine whether, given your RFC, your age, your education level, and your skill level, you should be able do any type of job.
An individual with borderline intellectual functioning should gather as much evidence of the above limitations as possible when applying for disability benefits. School records, testimony from teachers or supervisors, and other evidence may show a higher level of impairment than the IQ score alone might suggest. In addition, applicants should submit their IQ test scores to Social Security, making sure to include information about the standard deviation of the IQ test that was used. The standard deviation could indicate that test scores tend to be high and may not fully reflect the applicant’s disability.
For more information how Social Security assesses whether an applicant's mental and cognitive limitations rule out work, see our article on how Social Security uses mental RFCs to assess disability.