When a Social Security disability case turns on Residual Functional Capacity, the biggest problem often is not a missing diagnosis. It is a record that quietly makes someone appear more functional than their real day-to-day limitations suggest. The Social Security Administration evaluates RFC as the most a person can still do in a work setting on a regular and continuing basis — generally 8 hours a day, 5 days a week, or an equivalent schedule, based on all medically determinable impairments and related symptoms. That framing can become the center of the case. SSA’s RFC policy interpretation, 20 C.F.R. § 404.1545
If that concept feels abstract, it may help to start with a broader explanation of how functional limits shape disability decisions. In many cases, that is the lens adjudicators use to translate medical evidence into workplace restrictions.
This post walks through eight common RFC mistakes that can make a claimant look more work-capable than they are, why those mistakes matter, and what kinds of evidence often tell a fuller story.
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A very common RFC problem starts here: the file says what condition exists, but not what that condition stops the person from doing.
SSA’s rules distinguish between the existence of a medically determinable impairment and the separate question of how that impairment affects work functions. The agency considers exertional abilities like sitting, standing, walking, lifting, carrying, pushing, and pulling, and nonexertional limits like concentration, persistence, pace, social interaction, postural activities, and environmental tolerances. 20 C.F.R. § 404.1545, SSR 96-8p
That is why a record full of diagnoses — degenerative disc disease, lupus, PTSD, migraines, fibromyalgia, major depression — may still leave major gaps if it does not explain things like: