The honest answer: yes, but it is all about the process
Dismissing someone because ill health means they can no longer do their job is lawful in principle. It is called a capability dismissal, and it is a legitimate reason to end employment.
The catch is that a tribunal does not judge whether the absence was inconvenient for you. It judges whether you acted reasonably and followed a fair process. Acting too soon, or skipping steps because the business is under pressure, is what turns a fair decision into an unfair dismissal.
Before you even think about dismissal, make sure you can show a fair process behind it: medical evidence, genuine consultation, and consideration of alternatives.
First, the question that changes everything: is it a disability?
If the condition counts as a disability under the Equality Act, you take on extra legal duties, including making reasonable adjustments, and the protection for the employee is far stronger. Dismiss without dealing with this properly and a capability case can become a disability discrimination claim, which is uncapped at tribunal.
A condition is likely a disability if it has a substantial, long-term effect on normal day-to-day activities, meaning it has lasted or is likely to last 12 months or more. Many conditions owners do not expect can meet that test, including anxiety, depression and long-term back problems.
Assume disability law may apply until a medical opinion tells you otherwise. It changes your obligations entirely.
What a fair process actually looks like
Stay in regular, supportive contact and get up-to-date medical evidence, usually through an occupational health referral, so you understand the real prognosis rather than guessing.
Consult the employee properly. Talk through whether and when a return is realistic, and what might help. This is not a box-tick, it is where most fair outcomes are found.
Genuinely consider the alternatives before dismissal: reasonable adjustments, a phased return, reduced hours, or a different role. You need to be able to show you looked.
Only if there is genuinely no reasonable prospect of a sustainable return should you consider dismissal on capability grounds, with proper notice and a right of appeal.
No dismissal is safe until you have medical evidence, real consultation, and a proper look at alternatives behind it.
Where owners get this wrong
The common mistakes are predictable: dismissing before getting any medical evidence, ignoring the disability question, skipping consultation, applying a blanket absence trigger to a disability-related absence, or rushing the whole thing because the business is stretched.
Each one, on its own, can be enough for a tribunal to find against you, even when letting the person go was the sensible business decision.
Pressure to act fast is exactly when mistakes happen. The cost of a wrong dismissal dwarfs the cost of a few more weeks doing it properly.
Is there a cleaner alternative?
Sometimes, yes. Where the relationship has broken down or a fair capability process looks long and uncertain, a negotiated exit through a settlement agreement can be quicker and cleaner for both sides, with certainty and privacy built in.
It is not a shortcut around the rules, and it has to be approached in the right way, at the right time, with the correct legal protection. Done well, it can spare everyone a drawn-out process.
If a fair capability process looks long and uncertain, a properly handled settlement agreement can be a cleaner route, but only if it is set up correctly.
The bottom line
You can dismiss an employee who is off sick, but only on capability grounds, after a fair process, and with the disability question handled properly. Do it in a rush and you risk an unfair dismissal claim or, worse, an uncapped discrimination claim. Do it properly and the decision is defensible.
If you are at this point and not sure how serious it is or what to do first, the free Employee Situation Check gives you an honest read in a few minutes, with no login and no obligation.
Key takeaways
- Yes, you can dismiss someone who is off sick, but only on capability grounds and after a fair process.
- First check whether the condition is a disability, it adds legal duties and the claims are uncapped.
- A fair process means medical evidence, genuine consultation, and considering alternatives before any decision.
- A properly handled settlement agreement is sometimes a cleaner route for both sides.
- Get advice before you act. The cost of getting this wrong far outweighs the cost of doing it properly.