Managing Poor Performance at Work 2026 (UK Guide)

Managing poor performance is not simply a question of output. It is a legal and procedural issue that sits squarely within UK employment law. How an employer handles capability concerns can determine whether a later dismissal is fair or unlawful, and whether the business is exposed to discrimination or whistleblowing-related claims.

Managing poor performance requires a structured, documented and reasonable approach. Employers must distinguish capability from misconduct, provide support and a genuine opportunity to improve, and comply with statutory obligations under the Employment Rights Act 1996 and the ACAS Code of Practice. In some cases, additional duties arise under the Equality Act 2010.

Employment contracts often underpin the standards expected, the processes that apply and the notice and appeal rights that follow. For that reason, employers should ensure the relevant employment contract terms and any incorporated policies are clear, current and consistently applied.

What this article is about

This guide explains how to manage poor performance lawfully and effectively. It sets out the legal framework governing poor performance management, the difference between capability and misconduct, the correct staged approach to managing a poor performer and the risks associated with dismissal. It is written for UK employers and managers who need to ensure that the management of poor performance is both commercially sensible and legally defensible. It should be read alongside the Employment Rights Act 1996, including the fairness tests applied under section 98.

Section A: What Is Managing Poor Performance?

Managing poor performance refers to the structured process employers use to address concerns about an employee’s ability to meet the required standards of their role. In legal terms, this falls under “capability” which is one of the potentially fair reasons for dismissal under section 98(2)(a) of the Employment Rights Act 1996.

Capability is interpreted broadly. It includes the employee’s skill, aptitude, health or any other physical or mental quality that affects their ability to perform the work. In any capability-related dismissal, the employer must be able to show the reason for dismissal and, under section 98(4), the tribunal will assess whether the employer acted reasonably in treating capability as a sufficient reason to dismiss, taking account of the procedure followed and the circumstances as a whole.

Poor performance management is not about punishment. It is about identifying performance gaps, understanding their causes, supporting improvement and only escalating to dismissal where a fair and reasonable process has been followed. Where employers have a written capability procedure, it should normally be followed consistently unless there is a justified and documented reason to depart from it.

1. What counts as poor performance?

Poor performance arises where an employee is unable to perform their duties to the required standard. This may include failing to meet measurable targets or objectives, producing work of consistently inadequate quality, missing deadlines without reasonable explanation, demonstrating a lack of required competence or skill, or being unable to carry out key responsibilities of the role.

Performance concerns should be assessed objectively. Employers should rely on documented expectations, job descriptions, key performance indicators, measurable objectives or agreed standards rather than subjective dissatisfaction. In practice, employers are better protected where they can show a clear baseline of what “good performance” looks like for the role, and where that baseline has been communicated and applied consistently.

Poor performance can also present as behavioural issues that affect capability rather than conduct, for example persistent disengagement, poor organisation or recurring communication failures that prevent delivery of tasks. Employers should still focus on evidence and outcomes, and avoid framing capability issues as disciplinary matters unless the facts justify that categorisation.

2. Capability versus misconduct

A critical legal distinction in managing poor performers is the difference between capability and misconduct.

Capability concerns arise where the employee is trying but is not meeting the required standard, whether due to skill gaps, insufficient training, health issues, or difficulties coping with the role’s demands. Misconduct concerns arise where the employee is unwilling to comply, breaches policy, or deliberately refuses instructions.

For example, an employee who lacks technical competence or repeatedly makes errors despite support may be a capability issue. By contrast, an employee who refuses to follow lawful instructions or demonstrates deliberate non-compliance may be a misconduct issue, such as insubordination.

This distinction matters because the procedural route differs. Capability concerns are typically handled through a performance management or capability process. Misconduct is handled through a disciplinary process. Employers should avoid “shoehorning” performance problems into disciplinary procedures unless the evidence supports misconduct, as misclassification can undermine fairness and increase tribunal risk. Where a misconduct route is required, employers should follow an appropriate disciplinary procedure and apply the relevant standards for investigation and sanction.

For practical context, employers may find it helpful to cross-check the definitions and examples set out in guidance on misconduct at work when determining which route applies.

3. The legal framework for managing poor performance

The management of poor performance is governed primarily by the Employment Rights Act 1996, under which capability is a potentially fair reason for dismissal. However, establishing a fair reason is only part of the analysis. Tribunals focus closely on whether the employer acted reasonably and followed a fair process. That assessment is carried out under section 98(4), which looks at the circumstances of the case and whether the employer’s decision and procedure fell within the range of reasonable responses.

Employers should also consider the ACAS Code of Practice on Disciplinary and Grievance Procedures. The Code applies to capability procedures that may lead to warnings or dismissal for poor performance. It does not apply to redundancy dismissals. If an employer unreasonably fails to follow the Code, an employment tribunal may adjust compensation by up to 25% depending on the extent of the failure and its impact on fairness.

Employees also have procedural rights during performance processes. In particular, where a formal meeting could result in a warning or dismissal, employees generally have a statutory right to be accompanied by a fellow worker or trade union representative. Employers should ensure invitations and outcome letters reflect this right.

Finally, managing poor performance often intersects with equality obligations. Under the Equality Act 2010, employers may be required to consider reasonable adjustments where poor performance may be linked to disability. Where disability is in issue, employers should take care to assess whether they have actual or constructive knowledge of the disability and whether any unfavourable treatment is connected to something arising from disability. Employers should also be aware that certain defences may turn on whether any action taken is a proportionate means of achieving a legitimate aim, particularly where capability action risks being characterised as disability-related unfavourable treatment.

Failure to follow a fair process is one of the most common reasons capability dismissals are found to be unfair, even where the underlying performance concerns are genuine.

Section B: How to Manage Poor Performance Lawfully

Managing poor performance requires a staged, proportionate and well-documented approach. Tribunals do not expect perfection from employers, but they do expect reasonableness. The question in any unfair dismissal claim will be whether the employer acted within the range of reasonable responses and followed a fair procedure.

The management of poor performance should normally move from informal intervention to formal capability action, giving the employee a genuine opportunity to improve before dismissal is considered.

1. Early intervention and informal action

In many cases, poor performance can be resolved without initiating a formal process. Early conversations are often the most effective tool in managing a poor performer.

At this stage, the manager should identify specific performance concerns using objective examples, clarify the standards expected, explore whether there are underlying causes, offer appropriate support or training, and confirm expectations in writing.

These discussions should be constructive rather than accusatory. The purpose is to correct performance issues before they escalate. Although informal, managers should keep notes of discussions. If performance later deteriorates further, evidence of earlier support may become important in demonstrating fairness.

Where performance improves following informal intervention, no further action may be required.

2. Moving to a formal performance management process

If informal measures fail, the employer may move to a formal capability procedure.

At this stage, fairness becomes critical. The employer should write to the employee outlining the performance concerns, provide the evidence relied upon, invite them to a formal capability meeting, and inform them of their statutory right to be accompanied.

Under section 10 of the Employment Relations Act 1999, an employee has the right to be accompanied at a formal capability meeting by a fellow worker, a trade union representative, or an official employed by a trade union.

The companion may address the hearing, put and sum up the employee’s case, and confer with the employee, although they cannot answer questions on the employee’s behalf.

During the meeting, the employer should explain the concerns clearly, refer to documented evidence, allow the employee to respond, explore any mitigating factors, and consider whether additional support is appropriate. The outcome should be confirmed in writing.

3. Implementing a Performance Improvement Plan (PIP)

Although not a statutory requirement, a Performance Improvement Plan is widely regarded as best practice in poor performance management. A properly drafted plan also helps demonstrate that the employee was given a fair and reasonable opportunity to improve.

Employers often formalise this using a performance improvement plan, which should specify the performance deficiencies, set clear and measurable objectives, identify the support to be provided, define a reasonable timeframe for improvement, and confirm the potential consequences if standards are not met.

Objectives should be realistic and achievable within the timeframe set. What is reasonable will depend on the nature of the role, the complexity of the duties and the employee’s seniority. A PIP should not be used as a pretext for dismissal. If the targets are unattainable, the timeframe is unrealistic, or the outcome is predetermined, a tribunal may find the process unfair.

4. Monitoring progress and providing support

Managing poor performance does not end once a PIP is issued. Employers must actively monitor and support improvement. This may include regular review meetings, constructive feedback, additional training, adjustments to workload or supervision, and clear signposting of progress against targets.

If performance improves to an acceptable level, the matter should be closed formally and confirmed in writing. If improvement is partial but ongoing, it may be reasonable to extend the improvement period. However, extensions should not be indefinite, and employers should record why an extension is appropriate, what further improvement is required, and the revised review date.

5. Escalation and warnings

If the employee fails to meet the required standards within a reasonable timeframe, the employer may issue a formal written warning under the capability procedure.

The warning should set out the continuing deficiencies, confirm the improvement required, state the timeframe for further review, and explain that dismissal may follow if improvement is not achieved.

Progressive warnings often strengthen procedural fairness and reduce legal risk, but employers should still consider whether the steps taken are proportionate to the circumstances. In some situations, particularly involving serious incompetence or safety-critical roles, a shorter process may be reasonable. If an employer proceeds more quickly, it should be able to justify why that approach was appropriate and fair.

In all cases, employers should ensure their approach remains consistent with the ACAS Code of Practice, as unreasonable non-compliance can lead to an uplift in tribunal awards. For detailed guidance, see the ACAS Code of Practice.

Section C: Managing Poor Performance and Legal Risk

Managing poor performance is not simply an operational issue. It carries significant legal risk if mishandled. Many successful tribunal claims arise not because performance concerns were unfounded, but because the employer failed to follow a fair and reasonable process.

Employers must assess unfair dismissal exposure, discrimination risk and procedural compliance at every stage of the management of poor performance.

1. Unfair dismissal risk

Under section 98 of the Employment Rights Act 1996, capability is a potentially fair reason for dismissal. However, the existence of a fair reason is only the starting point. A tribunal will consider whether the employer genuinely believed the employee was underperforming, whether that belief was based on reasonable grounds following a reasonable investigation, and whether the employer acted within the range of reasonable responses.

Employees with two years’ continuous service generally have the right to claim ordinary unfair dismissal. Where that qualifying period is met, the burden falls on the employer to show both a fair reason and procedural fairness. For a broader overview of how tribunals approach these claims, see unfair dismissal.

It is important to recognise that certain claims do not require two years’ service. Dismissals connected to whistleblowing, pregnancy, trade union activities or the assertion of statutory rights may amount to automatically unfair dismissal from day one. Discrimination claims under the Equality Act 2010 also require no qualifying service. Employers should therefore avoid assuming that short service eliminates legal risk. For context, see automatically unfair dismissal and unfair dismissal under 2 years.

Failure to follow a fair procedure may render a dismissal unfair even where poor performance is clearly established. Tribunals regularly emphasise that procedural fairness is central to a lawful capability dismissal.

2. Disability and the Equality Act 2010

One of the most significant risks in managing poor performers arises where performance issues are linked to health conditions.

Under the Equality Act 2010, a person is disabled if they have a physical or mental impairment that has a substantial and long-term adverse effect on their ability to carry out normal day-to-day activities. Where an employer knows, or could reasonably be expected to know, that an employee is disabled, the duty to consider reasonable adjustments may arise.

Reasonable adjustments might include adjusting targets, modifying duties, providing additional training or equipment, altering working hours, or reallocating certain tasks. A failure to consider reasonable adjustments can result in liability for disability discrimination. Employers should therefore assess carefully whether performance concerns are connected to a disability and document the steps taken. For further guidance, see disability discrimination and reasonable adjustments.

Employers should also be aware of the risk of discrimination arising from disability. This occurs where an employee is treated unfavourably because of something arising in consequence of their disability, such as absence levels or reduced productivity. Such treatment may be unlawful unless the employer can show that it is a proportionate means of achieving a legitimate aim. Careful documentation of legitimate business reasons and consideration of alternatives is therefore essential.

3. Ill health and capability dismissals

Where poor performance stems from ill health rather than lack of skill, additional procedural safeguards are required.

A fair health-related capability dismissal typically requires up-to-date and sufficient medical evidence, meaningful consultation with the employee, consideration of reasonable adjustments, consideration of alternative roles or redeployment, and an assessment of prognosis and likely timescale for improvement.

Employers should consider whether to obtain medical reports or refer the employee to occupational health before making a final decision. Failure to obtain appropriate evidence or to consult meaningfully may render a dismissal unfair. For practical guidance, see occupational health.

The employer is not required to keep a role open indefinitely. However, it must balance operational needs against fairness and medical evidence, and ensure the decision falls within the range of reasonable responses.

4. Automatically unfair dismissal and retaliation risks

Employers must ensure that a capability process is not masking another prohibited reason for dismissal. If an employee has raised concerns about wrongdoing, safety or legal breaches, those concerns may constitute protected disclosures. Dismissal linked to such disclosures can amount to automatically unfair dismissal, regardless of length of service.

Similarly, dismissals connected to pregnancy, maternity leave, trade union activities or the assertion of statutory rights carry heightened risk.

Where an employee has recently raised concerns, lodged a grievance, or relied on statutory protections, employers should ensure that performance concerns are genuine, evidenced and unrelated to those protected activities. Clear documentation and consistent treatment are essential in defending such claims. Employers should also review their whistleblowing policy to ensure internal procedures are aligned with legal obligations.

5. Constructive dismissal risk

Mishandled performance management can also give rise to constructive dismissal claims. If an employer conducts a capability process in a manner that is oppressive, humiliating, predetermined or fundamentally unfair, the employee may argue that the employer has breached the implied term of mutual trust and confidence.

Examples of risk factors include imposing unrealistic targets, ignoring medical evidence, publicly criticising performance, or signalling that dismissal is inevitable regardless of improvement.

To reduce constructive dismissal risk, employers should ensure that performance management remains evidence-based, proportionate, and conducted with professionalism and respect. A fair and transparent process not only protects against unfair dismissal claims, but also reduces the risk of employees resigning and alleging breach of contract.

Section D: Dismissing for Poor Performance

Dismissal should be the final stage in managing poor performance, not the starting point. Even where performance concerns are genuine and well-evidenced, a dismissal will only be fair if the employer can demonstrate that it acted reasonably in all the circumstances and followed a procedurally sound process.

Capability dismissals are frequently scrutinised by employment tribunals. The fairness of the process is often more important than the severity of the performance shortcomings.

1. When dismissal for poor performance may be fair

A dismissal for poor performance is more likely to be fair where the employer can show that the performance concerns were genuine and supported by evidence, the employee was informed clearly of the required standards, the employee was given warnings and a reasonable opportunity to improve, appropriate support and training were provided, the employee was given the right to be accompanied at formal meetings, the consequences of continued underperformance were made clear, and a final review meeting took place before dismissal.

The timeframe for improvement must be reasonable. What is reasonable will depend on the complexity of the role, the seniority of the employee, the nature of the performance failings and the impact on the business. For example, a senior employee in a safety-critical position may justifiably be given a shorter improvement window than a junior employee in a developmental role.

Tribunals apply the range of reasonable responses test. The question is not whether the tribunal would have dismissed in the same circumstances, but whether dismissal fell within the band of reasonable responses open to a reasonable employer.

Where dismissal becomes necessary, employers should follow a clear capability route and ensure compliance with their internal policy and statutory obligations. For detailed guidance on the final stage of the process, see capability dismissal and practical steps outlined in how to dismiss an employee for poor performance.

2. When dismissal is likely to be unfair

Dismissal for poor performance is likely to be found unfair where no clear performance standards were set, the employee was not warned that their job was at risk, the employee was not given sufficient time to improve, the employer failed to investigate underlying causes, medical evidence was not obtained where health issues were raised, reasonable adjustments were not considered in disability cases, or the decision to dismiss was predetermined.

A common tribunal finding is that the employer moved too quickly from identifying poor performance to dismissal without allowing a genuine opportunity to improve. Even where performance is objectively weak, procedural unfairness can invalidate the dismissal.

Employers should also ensure that they offer a genuine right of appeal. A properly conducted appeal can correct earlier procedural defects and may be a significant factor in defending an unfair dismissal claim.

3. Alternatives to dismissal

Before dismissing for poor performance, employers should consider whether alternatives are reasonable. These may include redeployment to a more suitable role, demotion with the employee’s agreement, extension of the performance improvement period, additional training or supervision, or adjustment of duties.

There is no absolute obligation to redeploy in every case. However, failure to consider reasonable alternatives may undermine the fairness of a dismissal decision, particularly in larger organisations where suitable vacancies exist.

Where disability is involved, the obligation to consider redeployment may arise as part of the duty to make reasonable adjustments. Employers should document the roles considered, the reasons for acceptance or rejection, and any consultation with the employee.

4. Dismissal meeting and outcome

If dismissal is being considered, a final capability meeting should be convened. The employee must be informed that dismissal is a potential outcome, be given the right to be accompanied, and be given the opportunity to make representations before a final decision is taken.

If dismissal is confirmed, the employer should provide written confirmation of the decision, state the reasons clearly, confirm notice entitlement, and offer a right of appeal.

Even where an employee has less than two years’ service and cannot ordinarily claim unfair dismissal, employers should still ensure that contractual notice is honoured and that the process is not discriminatory or connected to a protected reason.

Dismissal for poor performance can be lawful where capability concerns are genuine and the employer has followed a fair, reasonable and documented process. In most cases, dismissal will only be defensible where it is demonstrably a last resort.

Section E: Best Practice in Managing Poor Performers

While managing poor performance often focuses on resolving individual cases, the most legally secure organisations take a preventative approach. Effective poor performance management systems reduce the likelihood of disputes, improve productivity and strengthen an employer’s defence if dismissal becomes necessary.

Managing poor performers successfully is less about reacting to failure and more about building structured, consistent performance frameworks across the business.

1. Implementing structured poor performance management systems

A clear and consistent performance management framework is the foundation of lawful management of poor performance.

Employers should ensure job descriptions are accurate and up to date, key performance indicators are measurable and objective, performance expectations are communicated clearly, reviews take place at regular intervals, and managers are trained to document performance discussions.

Performance systems do not need to be complex. However, they must be consistent. Tribunals often scrutinise whether an employee was judged against clear standards or shifting expectations. Where expectations are unclear or inconsistently applied, dismissal decisions become vulnerable.

2. Training managers to manage poor performance lawfully

Line managers are typically responsible for managing a poor performer in practice. However, many unfair dismissal cases arise because managers are unfamiliar with legal requirements.

Employers should provide training on the distinction between capability and misconduct, the statutory right to be accompanied, the ACAS Code of Practice, Equality Act obligations, documentation standards and conducting difficult conversations.

Managers should understand that managing poor performance is a procedural exercise as much as a commercial one. Consistency and documentation are legal safeguards, not administrative burdens.

3. Documentation and audit trails

Poor performance management should always generate a clear paper trail.

Employers should retain notes of informal discussions, copies of warning letters, performance improvement plans, records of review meetings, evidence relied upon and appeal documentation.

Tribunals assess fairness based on evidence. A well-documented process demonstrates reasonableness. A poorly documented process invites inference.

4. Probationary employees and early performance concerns

Where performance issues arise during probation, employers may have greater flexibility, particularly where the employee has less than two years’ service. However, contractual notice must still be honoured and the process must not be discriminatory or automatically unfair.

Even during probation, it is good practice to follow a structured review process and provide feedback. Employers should ensure that any probation management aligns with their written probation period policy and is applied consistently.

5. Consistency and internal complaints

Inconsistent treatment of similar cases can undermine the fairness of dismissal decisions. Employers should ensure policies are applied uniformly and any deviation from standard procedure is justified and documented.

Where an employee raises concerns about the way performance is being managed, those concerns may amount to a formal complaint. Employers should ensure such issues are addressed under their grievance procedure to avoid compounding risk.

Managing Poor Performance FAQs

What is managing poor performance?

Managing poor performance is the structured process employers use to address concerns about an employee’s capability to meet required standards. It involves identifying performance gaps, providing support and a reasonable opportunity to improve, and escalating through a fair procedure if standards are not met.

How do you manage poor performance lawfully?

To manage poor performance lawfully, employers should follow a staged process: clarify expectations, address concerns informally where possible, move to a formal capability procedure if needed, provide a reasonable opportunity to improve, and comply with the ACAS Code of Practice. The process must be documented and proportionate.

Is a Performance Improvement Plan legally required?

A PIP is not a statutory requirement. However, what the law requires is that the employee is informed of the concerns, given clear standards to meet, supported appropriately and allowed a reasonable opportunity to improve before dismissal is considered.

How long should a PIP last?

There is no fixed legal timeframe. A reasonable period will depend on the complexity of the role, the seriousness of the performance concerns and the time needed to demonstrate improvement. Many employers use 30 to 90 days as a guide, but shorter or longer periods may be justified.

Can you dismiss an employee for poor performance?

Yes. Capability is a potentially fair reason for dismissal under the Employment Rights Act 1996. However, dismissal will only be fair if the employer acted reasonably, followed a proper procedure, provided warnings and allowed a genuine opportunity to improve.

Do employees have the right to be accompanied?

Employees have a statutory right to be accompanied at formal capability meetings that may result in a warning or dismissal. The companion may be a fellow worker or a trade union representative and may address the meeting and confer with the employee.

What if poor performance is caused by illness or disability?

If performance issues are linked to a health condition, employers must consider whether the employee may be disabled under the Equality Act 2010. Where disability is established, the employer has a duty to consider reasonable adjustments before progressing to dismissal.

Can you dismiss during probation?

Employees with less than two years’ service generally cannot claim ordinary unfair dismissal. However, dismissals must still avoid discrimination and automatically unfair reasons, and contractual notice must be respected.

Conclusion

Managing poor performance requires more than identifying underperformance. It demands a structured, proportionate and legally compliant approach grounded in capability law under the Employment Rights Act 1996 and procedural fairness under the ACAS Code of Practice.

Employers who manage poor performance effectively begin with clear expectations, intervene early, provide meaningful support and document each stage of the process. Where formal action becomes necessary, employees must be given a reasonable opportunity to improve and a fair hearing before dismissal is considered.

Legal risk most commonly arises from procedural shortcuts, failure to consider health or disability issues, inconsistent application of policy or retaliatory decision-making. Tribunals focus not only on whether performance was inadequate, but whether the employer acted reasonably in all the circumstances.

A disciplined, documented and fair approach is essential to managing poor performance lawfully in the UK workplace.

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