What counts as a disability in law

A lot of people assume they are not covered by disability discrimination law because no doctor has used the word “disabled”, because their condition varies from week to week, or because they manage to get through most days without it showing. Here is how the test actually works.

The legal test

Under the Equality Act 2010The main piece of legislation protecting employees from discrimination at work. It covers nine protected characteristics including age, disability, sex, race, and religion, and makes it unlawful for a..., you have a disability if you have a physical or mental impairment that has a substantial and long-term adverse effect on your ability to carry out normal day-to-day activities.

Each part of that test matters on its own:

• Impairment covers physical conditions and mental health conditions alike. There is no list of qualifying conditions to check yourself against.
• Substantial means more than minor or trivial, not severe and not permanent. The Employment Appeal Tribunal confirmed in Nissa v Waverly Education Foundation that this threshold is deliberately set low.
• Long-term means the effect has lasted 12 months, is likely to last 12 months, or is likely to last for the rest of your life.
• Normal day-to-day activities means ordinary things: walking, concentrating, managing pain, sleeping, socialising, carrying out household tasks. It is not limited to work-related tasks.

An impairment does not have to be constant to meet the long-term test. If it comes and goes, the law treats its effects as continuing where they are likely to recur, not just where they run for 12 months without a break. A tribunal used this to find an employee with a recurring hernia disabled, even though he had experienced its effects for only around three monthsThe standard time limit for bringing most employment tribunal claims, running from the date of the act complained of. Because the limit is three months less one day, you should not wait until what fee... by the time of his dismissal, because he had been told the hernia was likely to come back.

You do not need a formal diagnosis

Nissa confirmed that the test is about effect, not label. A tribunal does not ask whether a doctor has named your condition. It asks whether the impairment substantially affects what you can do.

Medical evidence from your own treating clinicians, your GP, a consultant, a therapist, should generally be accepted at face value. Your employer cannot simply set aside a letter from your GP because they think it overstates things. They would need proper grounds to dispute it, not just a preference for a different view.

Coping well does not count against you

People get this part wrong most often: if you have built routines, habits, or workarounds that help you manage day to day, that does not reduce your legal protection.

The law looks at the underlying impairment, not the coping layer you have built around it. The same principle applies to medication and treatment: where treatment is currently controlling your symptoms, the assessment asks what your condition would do without it, not how well you are managing with it in place. J v DLA Piper turned on exactly this point: a tribunal cannot decide you are not disabled just because medication is working.

Why this matters

The definition of disability is not just an abstract legal category. It is the first hurdle in any disability discrimination claim, and in any request for reasonable adjustmentsChanges an employer must make under the Equality Act 2010 for a disabled employee, where without them the employee would be at a substantial disadvantage compared to non-disabled colleagues. What coun.... If you do not meet this threshold, the rest of the protection in the Equality Act does not apply to your situation, however unfair your treatment might otherwise feel.

Getting the threshold right, early, matters more than most people realise. If you assume you are not covered and do not raise it, you may lose the chance to ask for adjustments or challenge treatment that the law would otherwise have protected you against.

What to do if you think this applies to you

Start gathering medical evidence now rather than later. Ask your GP or consultant to put in writing how your condition actually affects your day-to-day activities, not just its name.

Think in terms of effect, not diagnosis. Write down what you struggle with or cannot do, including how long it has lasted and whether it is likely to continue. If you manage your condition with medication, routines, or workarounds, note what things would look like without them.

If you are trying to work out what your employer should be doing differently once your disability is established, our guide on reasonable adjustments explains the duty in full. If you want to talk through whether your situation meets this threshold, you can book a call with us.