Understanding disability in UK employment law under the Equality Act 2010

Employers have a legal duty under the Equality Act 2010 (the 2010 Act) to prevent disability discrimination and provide appropriate support  make reasonable adjustments to employees and job applicants who are disabled. However, many employers are unsure about how “disability” is defined under the law.

This article demystifies the legal definition and explains how it applies in practical terms to help employers remain compliant and inclusive.

Legal definition of disability under the Equality Act 2010

Under section 6 of the Equality Act 2010, a person is considered disabled if:

“They have a physical or mental impairment, and the impairment has a substantial and long-term adverse effect on their ability to carry out normal day-to-day activities.”

Each element of this definition carries specific legal meaning:

1. Physical or mental impairment

This can include:

• Physical impairments (e.g. mobility issues, sensory impairments, chronic illnesses)
• Mental impairments (e.g. depression, anxiety disorders, schizophrenia, learning difficulties)

The law does not require a formal medical diagnosis, although in practice, medical evidence is often relevant.

2. Substantial adverse effect

The impairment must have a more than minor or trivial impact. This means it affects the individual’s ability to function in a meaningful way — such as:

• Difficulty in walking or other manual dexterity
• Struggles with concentrating, remembering or communicating
• Challenges with time management, social interaction or personal care

3. Long-term condition

The impairment must:

• Have lasted or be expected to last at least 12 months, or;
• Be likely to last for the rest of the person’s life.

Recurring or fluctuating conditions can still meet this criterion.

4. Impact on day-to-day activities

They include ordinary activities like:

• Getting dressed
• Washing
• Using public transport
• Communicating with others
• Managing time
• Preparing meals
• Lifting, walking, or reading

Tribunals are also entitled, in appropriate circumstances, to take into account the effect on an employee of circumstances which only arise at work.

Which Conditions Are Covered By The Equality Act?

Some conditions are explicitly always recognised as disabilities under the 2010 Act, such as:

• Cancer
• HIV infection
• Multiple sclerosis (MS)

These are deemed disabilities from the point of diagnosis, regardless of their impact at the time. Therefore, employers should not wait for symptoms to worsen before taking appropriate steps to provide support.

Case Study: Employment tribunal made error when determining that claimant with autism and ADHD was not disabled

Neurodiverse conditions such as autism spectrum disorder (ASD), attention deficit hyperactivity disorder (ADHD), and dyslexia may also be covered if they meet the statutory criteria.

In the recent Employment Appeal Tribunal (EAT) case of Stedman v Haven Leisure Ltd, the EAT considered an appeal against a tribunal’s finding that a job candidate with ASD and ADHD was not disabled for the purposes of the 2010 Act.

The tribunal had accepted that Mr Stedman had a mental impairment but concluded it did not have a substantial adverse effect on his ability to carry out normal day-to-day activities. The EAT held that the tribunal had applied the wrong legal tests, failing to consider key principles, including:

• Comparing the claimant’s functioning with and without the impairment.
• Recognising that impairment affecting just one day-to-day activity can suffice.
• Avoiding offsetting strengths in some activities against weaknesses in others.

Furthermore, the EAT observed that a clinical diagnosis of ASD or ADHD is relevant not only to establishing impairment but also to evaluating substantial adverse effect, as it reflects a significant deviation from normal functioning.

The case was remitted to a new tribunal for reconsideration

Which Conditions Are Not Covered Under The Equality Act 2010?

The Act excludes certain conditions unless they meet the criteria. These include:

• Addictions to non-prescribed substances (e.g. alcohol, nicotine, drugs)
• Tendency to steal or set fires
• Seasonal allergies such as hay fever (unless severe and long-term)

Practical guidance for employers

• Don’t wait for a formal declaration: If you suspect an employee may be disabled under the Act, you should explore potential support and adjustments.
• Focus on impact, not diagnosis: The legal definition focuses on how a condition affects someone’s day-to-day life, not just its label.
• Explore expert input: Seek occupational health or other appropriate professional advice if you suspect someone may meet the criteria.
• Document steps taken: Record decisions carefully and ensure HR practices reflect an understanding of disability rights.
• Foster an inclusive culture: where employees feel safe disclosing health conditions.

Do you need employment law support on disability?

Understanding your legal obligations under the Equality Act 2010 is essential to reducing the risk of disability discrimination claims. We help clients not only stay compliant, but foster a genuinely inclusive workplace that empowers your workforce.

Explore what AfterAthena’s employment law team can do to support you with our fixed-rate retained service, or contact us here to speak with an expert.