Ill health dismissal: when it is fair and when it is not

Your employer can lawfully dismiss you because of ill health. It is a form of capability dismissal. But it can only do so fairly after a proper process, and if your condition is a disability the bar is higher still.

Long-term absence vs frequent short absences

• Long-term absence: you have been off for an extended period and a return is uncertain. The key question is how long a reasonable employer should wait. See long-term sick pay for your pay position meanwhile.
• Frequent short absences: repeated sick days with no single underlying cause. Employers often treat these more like an attendance issue, with warnings and review periods.

What a fair process requires

ACAS guidance and tribunal case law point to the same steps:

• Consultation. Your employer must talk to you about your health, prognosis and what might help. Dismissing someone without discussing it is rarely fair.
• Medical evidence. A reasonable employer gets an up-to-date view, often an occupational health report or a letter from your GP (with your consent). Fit notes alone are rarely enough to justify dismissal.
• Adjustments and alternatives. Phased return, reduced hours, different duties, homeworking or a different role should be explored.
• Warning. You should be told that dismissal is a possibility, and have a formal meeting where you can respond with a companion.
• Appeal. You should be offered one.

ACAS suggests dismissal may be considered where medical evidence shows you are unlikely to return within a reasonable timescale, or the business genuinely cannot sustain the absence. Size and resources matter: a large employer is expected to wait longer than a five-person firm.

Disability changes everything

Many long-term conditions, including cancer, MS, HIV, many mental health conditions and conditions lasting or likely to last 12 months with a substantial effect on daily life, count as disabilities under the Equality Act 2010. Then:

• Your employer must make reasonable adjustments, which can include discounting disability-related absence from triggers
• Dismissal for something arising from your disability is unlawful unless your employer can show it was a proportionate means of achieving a legitimate aim
• There is no qualifying service and no cap on compensation, which includes injury to feelings

Read more in disability discrimination.

Being dismissed while off sick

You can be dismissed while on sick leave, but the process above still applies. Our guide on being dismissed on sick leave explains your notice pay and sick pay position. Statutory sick pay has been payable from day one since 6 April 2026; see statutory sick pay.

Example: Claire, a warehouse supervisor with eight years' service, was off for five months after back surgery. Her employer dismissed her without an occupational health report, ignoring her surgeon's letter predicting a return to light duties within six weeks. That is a strong unfair dismissal and disability discrimination case, and it settled for a sum well above what her basic award alone would have been.

Was your PIP really about health?

Sometimes ill health is managed as poor performance instead. If you were put on a performance improvement plan while struggling with a condition your employer knew about, that can itself be a failure to make adjustments.

Questions to ask at an absence meeting

• What does the occupational health report say, and can I see it before decisions are made?
• What adjustments have been considered and why were any rejected?
• Is there an alternative role I could do, temporarily or permanently?
• How long is the business prepared to wait, and why?
• Will disability-related absence be discounted from any trigger points?

Bring a companion and take notes. If your health makes a meeting difficult, ask for it to be held at home, by video, or for written submissions instead. Refusing every meeting can backfire, because an employer can eventually decide on the evidence it has.

Ill health retirement and income protection

Before agreeing to leave, check whether your pension scheme offers ill health retirement or whether your employer has permanent health insurance. Dismissing you could end your entitlement to those benefits, and a tribunal may treat that as a significant loss. Ask HR for scheme details in writing.

Time limits

You normally have three months less one day from dismissal to start ACAS early conciliation. Ordinary unfair dismissal needs two years' service now, and six months for dismissals with an effective date on or after 1 January 2027.

If you are facing an ill health process or have already been dismissed, get advice early. Match My Solicitor matches you with an employment solicitor for a free initial conversation. Tell us about your situation, or see our discrimination service.