Can You Be Dismissed While on Sick Leave?

Being unwell is hard enough without worrying about your job on top of it. One of the first questions people ask when they’re signed off work is a simple one: can my employer dismiss me while I’m off sick?

The short answer is yes, but that answer comes with a long list of conditions. Dismissal during sick leave is lawful only where a strict set of rules have first been followed by your employer, and in practice many employers get those rules wrong. They act too quickly, rely on thin medical evidence, or skip the proper conversations. That is precisely where unfair dismissal claims or disability discrimination claims can arise.

So the real question is not whether you can be dismissed while on sick leave. It is whether your employer has done things properly.

The Legal Position

Dismissal during sick leave is lawful, provided the employer has a fair reason and follows a fair process first.

Where sickness is the issue, the fair reason almost always falls into one of two categories: capability, meaning a long-term illness is preventing you from doing your job, or “some other substantial reason,” which can cover situations where the business genuinely can no longer absorb your absence. Both sit within the framework of the Employment Rights Act 1996, which remains the main statute governing unfair dismissal. The Equality Act 2010 also plays a significant role, particularly where the illness amounts to a disability.

One point that often gets missed: a dismissal can be lawful in principle and still be unfair in practice. Employers frequently have a defensible reason on paper but fall down on process. When that happens, the dismissal remains open to challenge, and the tribunal’s focus shifts from why the decision was made to how.

Short-Term Versus Long-Term Absence

The length of your absence matters. Shorter illnesses are generally expected to be managed with support and patience.  Repeat short term illnesses often attract more robust employer attention.  A few weeks off with a clear recovery plan is rarely grounds for dismissal, and an employer who moves to terminate on that basis will usually be on very weak ground.

Long-term sickness absence is different. After an extended period off work, an employer may begin a process to assess whether you are likely to return and, if so, when. Before reaching any decision, they should weigh a range of factors: your likely return date, the medical evidence from your GP and Occupational Health, the operational impact of your absence, and the cost of covering your role through temporary staff or overtime.

This is not a box-ticking exercise. Employers are required to consider these factors genuinely, not simply to rehearse them as cover for a decision already made.

Process: Where Most Employers Go Wrong

Process is where dismissals on sick leave most often come unstuck. Even with a legitimate reason, a dismissal will not stand if the process behind it was unreasonable.

A fair process normally involves three things: obtaining proper medical evidence (usually from both your GP and an Occupational Health assessment), holding a meaningful consultation with you (a conversation, not an announcement), and properly considering alternatives, such as adjustments to your role, reduced hours, or a different position altogether.  If your employer has made any applicable adjustments, given you a chance to work with those adjustments and you still cannot do your role, you employer may be able to dismiss you fairly and legally.

Tribunals apply what is known as the “reasonableness test,” and one of the central questions is whether the employer could have waited longer for you to return. There is no fixed answer. It depends on the size of the employer, the nature and likely duration of the illness, and the impact of the absence on the business.

Tribunals have repeatedly found dismissals unfair where the employer relied on inadequate Occupational Health input or failed to consult properly before making a decision. Most successful claims are not really about the decision to dismiss. They are about the path the employer took (or failed to take) to get there.

Day-One Protection and Disability Discrimination

Two points of law are worth understanding clearly.

The first concerns the qualifying period for unfair dismissal. The Employment Rights Act 2025, which received Royal Assent in December 2025, will reduce the qualifying period from two years to six months with effect from 1 January 2027. This is a meaningful shift, but it is not the day-one right the government originally proposed. That proposal was dropped during the Bill’s final stages. Employees dismissed on sick leave before reaching six months’ service will still, in most cases, be unable to bring an ordinary unfair dismissal claim.

The second point is far more important for anyone dismissed while unwell, and it applies now. If your illness amounts to a disability under the Equality Act 2010, you have protection from day one of your employment. A disability, in the Act’s terms, is a physical or mental impairment with a substantial and long-term adverse effect on your ability to carry out normal day-to-day activities. “Long-term” generally means it has lasted, or is expected to last, twelve months or more. Many employees with serious or chronic illnesses meet this definition (and have protection)  without realising it.

Where the Equality Act applies, the employer owes you additional duties: to consider whether you could be redeployed into another role, and to make any reasonable adjustments to support your return. A dismissal that skips these steps can be unfair and discriminatory.

Medical Evidence

Medical evidence is often where these cases become contested. It is not unusual for a GP to sign an employee off as unfit to work while an Occupational Health report suggests a return may be possible. So whose view should the employer follow?

As a rule, employers are entitled to rely on Occupational Health advice, provided the assessment is thorough, balanced, and properly informed. A rushed report, a superficial review, or one that has missed material information about your condition can be challenged, and poor Occupational Health input is a recurring feature of successful unfair dismissal claims.

This is often the point at which legal advice pays for itself, because a careful review can expose either flaws in the medical evidence itself or flaws in how the employer has relied on it.

Reasonable Adjustments

If your condition qualifies as a disability, your employer’s obligations go further than fair process. They must actively consider how to help you stay in work, rather than treating dismissal as the default destination.

In practice, reasonable adjustments can include redeploying you to another role, modifying your duties, offering flexible or reduced hours, or supporting a phased return. These are not gestures of goodwill. They are signs of an employer taking its legal duties seriously, and employees have won unfair dismissal cases precisely because their employer failed to consider alternative roles or meaningful adjustments before moving to dismiss.

An employer who simply asserts that there was nothing else available will not get far. They have to show they genuinely looked.

Sick Pay and Notice

From 6 April 2026, Statutory Sick Pay changed significantly. SSP is now payable from the first day of sickness absence, with the three waiting days abolished, and the Lower Earnings Limit has also gone, meaning part-time and lower-paid employees who were previously excluded are now eligible. SSP is currently paid at 80% of average weekly earnings or the statutory flat rate of £123.25 per week, whichever is lower. For many workers in less secure employment, this is a substantial improvement.

Notice pay is a separate question. If you are dismissed, your entitlement to your contractual or statutory notice period does not disappear because you were ill. Employers cannot quietly stop paying you at the end of your employment simply because you have been off sick. There are complex rules about whether full pay is due on notice during sick leave.

When Dismissal Is Automatically Unfair

In some situations, dismissal is automatically unfair regardless of length of service. These include dismissals connected to pregnancy or pregnancy-related illness, dismissals for whistleblowing, and dismissals for asserting a statutory right. In those cases, there is no qualifying period: protection applies from day one.

It is also worth knowing that an employee forced to resign because of their employer’s conduct and undermining of the employment relationship may have a claim for constructive dismissal. Under current law, constructive dismissal generally still requires two years’ service (reducing to six months from January 2027), unless the reason behind it falls into one of the automatically unfair categories above.

Settlement Agreements: A Common Outcome

Many sickness-related disputes never reach a tribunal. Instead, they are resolved through a settlement agreement: binding legal agreements under which the employee waives their right to bring claims in exchange for an agreed financial package and departure terms.

For senior and higher-earning employees, settlement agreement values can be substantial. They often cover enhanced compensation, LTIPs and equity, a proportion of bonus and benefits, and provisions protecting confidentiality and reputation. Handled well, a settlement gives both sides a clean and predictable outcome.

Timing matters. Taking legal advice early, before the employer has locked in their position, tends to produce materially better exit terms, both on the headline figure and on how the agreement is structured.

The Bottom Line

Can you be dismissed while on sick leave? Yes, but only where the employer has a fair reason, follows a fair process, and acts reasonably throughout. The margin for error is narrow, and it is getting narrower. The reduced qualifying period coming in January 2027 and the breadth of disability discrimination protection together mean that employees on sick leave are far from powerless, and employers who cut corners are increasingly likely to be challenged.

If you are off sick and worried about being dismissed or if you have been dismissed while on sick leave, David advises employees on whether the decision and the process behind it can be challenged, and on the options available, from unfair dismissal and disability discrimination claims to negotiating a settlement agreement on the best possible terms.