Workplace grievances can arise for many reasons. An employee might challenge a management decision, complain about bullying, question a pay decision, raise concerns about discrimination or argue that an internal investigation was incomplete.
For employers, handling these complaints fairly is important. A clear grievance procedure helps managers understand their responsibilities, gives employees a structured way to raise concerns and can reduce the risk of disputes escalating.
This raises an important question: how can an employer limit grievance appeals to specific grounds under UK law without making the process unfair?
The answer requires a balance between having a controlled, clearly defined appeals process and preserving a meaningful opportunity for employees to challenge a grievance decision.
UK employment law does not provide a single exhaustive statutory list of grounds on which every grievance appeal must be permitted. Employers can set out reasonable grounds in their internal policies, explain how appeals must be submitted and establish practical time limits. However, they should not use a restrictive policy to prevent legitimate challenges to an incorrect decision or an unfair procedure.
The Acas Code of Practice on disciplinary and grievance procedures states that employees who feel their grievance has not been satisfactorily resolved should appeal and explain their grounds in writing without unreasonable delay. Appeals should be heard without unreasonable delay and handled impartially, wherever possible by a manager who has not previously been involved. The outcome should be communicated in writing.
This guide explains the main appeal grounds employers can specify, how to draft a policy, what employees should know, and the practical steps organisations can take to manage grievance appeals lawfully.
This article provides general information about employment law in Great Britain. Northern Ireland has a separate employment relations framework, so employers there should check the relevant Labour Relations Agency guidance.
1. What Is a Grievance Appeal?
A grievance appeal is a formal request for an employer to reconsider the outcome of an employee’s workplace complaint.
An employee may raise a grievance about matters such as:
- Bullying, harassment or inappropriate workplace behaviour.
- Discrimination or unequal treatment.
- Pay, contractual terms or working conditions.
- Management decisions or workplace procedures.
- Working relationships with colleagues or managers.
- Health and safety concerns.
- The way a complaint was investigated.
- An outcome that does not adequately address the problem.
An appeal normally takes place after the employer has considered the original grievance and communicated its decision.
The purpose is not necessarily to repeat the entire grievance investigation. It is to examine whether the original decision was fair, reasonable and supported by the available evidence, and whether further action is required.
According to Acas guidance on appealing a disciplinary or grievance outcome, an appeal can challenge an outcome that is wrong, a procedure that was unfair or new evidence that may affect the decision.
This is why employers should distinguish between defining appeal grounds and preventing appeals altogether. The first can help organise the process. The second can create significant legal and employee-relations risks.
2. What Does UK Law Say About Restricting Grievance Appeal Grounds?
There is no universal statutory checklist that limits all workplace grievance appeals to a fixed number of grounds.
Instead, employers should consider the applicable employment law, their own grievance policy, contractual commitments and the Acas Code of Practice.
The following legal principles are particularly relevant.
A. Employees should be offered an opportunity to appeal
The Acas Code states that employers should allow employees to appeal against formal decisions made under disciplinary and grievance procedures.
For grievances, paragraph 41 states that an employee who feels their grievance has not been satisfactorily resolved should appeal and explain the grounds in writing without unreasonable delay.
A policy can set out the types of issues an appeal should address. However, a blanket rule that only permits appeals on narrow technical grounds may undermine the purpose of the appeal stage.
B. Employers should follow their own grievance procedure
GOV.UK explains that employers must set out a grievance procedure and share it in writing with employees. The procedure should explain how to appeal a grievance decision, including relevant arrangements and time limits.
If the procedure is incorporated into an employment contract, failing to follow it may also create a potential breach of contract issue.
Employers should therefore check whether proposed appeal restrictions conflict with their existing handbook, employment contracts or established procedures.
Official guidance: GOV.UK — Handling an employee’s grievance.
C. The Acas Code is not itself a statute, but it has legal significance
The Acas Code is not directly legally binding in the same way as an Act of Parliament. However, employment tribunals must take it into account where relevant.
In applicable cases, a tribunal may adjust an award by up to 25% where an employer or employee has unreasonably failed to comply with the Code.
This does not mean every procedural mistake automatically results in compensation. The consequences depend on the legal claim, the circumstances and the tribunal’s findings.
D. Some grievances involve separate legal rights
Employers should be particularly careful when a grievance concerns alleged discrimination, whistleblowing, health and safety, unlawful deductions from wages or another statutory right.
A restrictive internal appeal policy cannot remove statutory protections or prevent an employee from pursuing an external legal remedy where the law permits it.
An employee may also have a claim even if they did not complete an internal appeal. Conversely, raising an appeal does not automatically extend an employment tribunal deadline.
Practical point: Internal grievance appeals and external legal claims are different processes. Employers should not suggest that an internal appeal is the only route available to an employee.
3. The Main Grounds Employers Can Include in a Grievance Appeal Policy
A practical policy can identify the main reasons an employee may request a review. The grounds below are useful starting points, rather than an exhaustive legal list.
1. The original decision was wrong or unreasonable
An employee may argue that the grievance outcome was incorrect because the findings do not reflect the evidence or the conclusions are not reasonably supported.
For example, an employee complains that their manager repeatedly made inappropriate remarks. The investigation accepts that some comments were made but concludes that the behaviour was not inappropriate without adequately explaining why.
The employee may appeal because they believe the findings or conclusions are wrong.
What the employer should do: Review the relevant evidence, the reasoning behind the decision and whether the outcome remains reasonable.
2. Relevant evidence was overlooked
An appeal may identify evidence that the original decision-maker failed to consider.
Examples include:
- Relevant emails or written messages.
- Witness statements.
- Meeting records.
- Workplace policies.
- Relevant payroll or attendance records.
- Documents that contradict a material finding.
An employer can ask the employee to identify the evidence and explain its relevance. It should not automatically reject an appeal merely because the original investigator has already completed an investigation.
3. New evidence has become available
New evidence may emerge after the original grievance outcome.
For example, an employee may receive an email that was not available during the initial investigation, or a witness may provide relevant information that could not reasonably have been obtained earlier.
A policy can ask employees to explain why the evidence was not provided previously and how it might affect the outcome.
However, employers should avoid an inflexible rule that excludes all new evidence. The relevance, reliability and circumstances of the evidence should be considered.
4. The investigation was incomplete
An employee may argue that the employer did not investigate the complaint adequately.
Possible concerns include:
- Relevant witnesses were not interviewed.
- Important documents were not reviewed.
- Material inconsistencies were not addressed.
- The investigator failed to explore a significant allegation.
- The employee was not given a reasonable opportunity to explain their complaint.
The employer should consider whether further investigation is necessary. It may be appropriate to reopen part of the investigation rather than repeat every step.
5. The grievance procedure was not followed fairly
A grievance appeal can challenge a procedural problem.
Examples include:
- A required meeting was not held.
- The employee was not given a reasonable opportunity to explain their case.
- A relevant policy requirement was ignored.
- The decision-maker had a conflict of interest.
- The outcome did not address a significant part of the grievance.
- The employee was not informed of the reasons for the decision.
Not every procedural error necessarily invalidates an outcome. The employer should consider the nature of the error, its effect on fairness and whether it could have influenced the decision.
6. The outcome did not resolve the grievance
An employee may accept that the investigation was conducted properly but remain dissatisfied with the action proposed.
For example, the employer may acknowledge poor communication between managers but offer no practical steps to address the problem.
An appeal may explain why the proposed resolution is insufficient and what reasonable action the employee is seeking.
The employee does not automatically have a right to demand their preferred outcome. The employer should nevertheless consider whether the original response adequately addresses the complaint.
7. The outcome was inconsistent with comparable cases
An employee may argue that their grievance was treated differently from similar complaints without a reasonable explanation.
For instance, a company may have followed a particular process in previous cases involving similar conduct but departed from that process in the employee’s case.
The employer should examine whether the situations are genuinely comparable and whether any difference in treatment is justified.
Consistency is important, but it does not require identical outcomes where the facts or relevant circumstances differ.
8. There may have been bias or a conflict of interest
An employee may question whether the grievance was handled impartially.
For example, the person deciding the grievance may have been directly involved in the disputed events or may have expressed a predetermined view.
The employer should consider whether the concern is supported by the available information and whether a different decision-maker should handle the appeal.
Acas recommends that appeals should, wherever possible, be dealt with by a manager who has not previously been involved.
9. The outcome may involve a legal or policy error
An employee may argue that the employer has misapplied an internal policy, contractual provision or relevant legal requirement.
Examples include a disputed interpretation of a contractual benefit, an incorrect application of a workplace policy or a failure to consider an allegation of discrimination appropriately.
The employer should assess the specific issue rather than treating the appeal as a general disagreement with management.
Where the complaint raises a potentially serious legal issue, specialist employment law advice may be appropriate.
4. Can Employers Make These Grounds an Exhaustive List?
Employers can identify recognised appeal grounds to help employees submit focused appeals and help managers conduct consistent reviews. However, describing the list as completely exhaustive can be risky if it prevents a legitimate complaint from being considered.
A safer policy approach is to state that appeals may be brought on one or more recognised grounds including, but not limited to, the categories listed in the policy.
An employer may then explain that an appeal should identify:
- The part of the grievance outcome being challenged.
- The reason the employee believes it was wrong or unfair.
- The relevant evidence or procedural concern, where applicable.
- The action the employee would like the employer to consider.
This approach provides structure without suggesting that an employee must fit every concern into a narrow category.
Example: Restrictive wording versus balanced wording
Riskier wording:
“Grievance appeals will only be accepted where there is a proven procedural error or new evidence. Appeals based on disagreement with the outcome will not be considered.”
This wording may exclude a legitimate appeal where the employee believes the original findings or decision were wrong, even if no new evidence exists.
Better wording:
“An employee may appeal a grievance outcome on one or more grounds, including that the decision was incorrect or unreasonable, relevant evidence was overlooked, new evidence has become available, the investigation or procedure was unfair, or the outcome did not adequately resolve the grievance. The grounds listed are examples and do not prevent the employer from considering other relevant concerns. Appeals will be reviewed fairly and impartially.”
This gives employees guidance while preserving the employer’s ability to assess each case on its merits.
5. How to Draft a Fair Grievance Appeal Policy: A Practical Checklist
Employers should consider the following elements when creating or updating their policy.
1. Explain who can submit an appeal
State that employees who remain dissatisfied with a formal grievance outcome may appeal under the procedure.
Explain whether the policy covers former employees and how an appeal should be submitted where employment has ended, taking account of the circumstances and any applicable contractual arrangements.
2. Set out the recognised grounds
Include the main grounds described above, such as an incorrect decision, overlooked evidence, new evidence, procedural unfairness, inadequate investigation and an unresolved grievance.
Use clear language that employees without legal training can understand.
3. Explain how an appeal must be submitted
Specify the appropriate recipient, such as HR or a designated manager. Provide an alternative where the normal recipient is involved in the grievance.
Ask employees to set out their grounds in writing and identify any evidence they want considered.
Avoid unnecessary administrative requirements that could prevent an otherwise legitimate appeal from being heard.
4. Set a reasonable time limit
An employer can establish a time limit in its policy, provided it is reasonable and applied fairly.
Acas recommends that employees submit an appeal as soon as possible and suggests five working days from receiving the outcome as an appropriate period. This is an Acas recommendation, not a universal statutory deadline applying to every workplace.
The policy should explain when the period begins and how an employee can request an extension where there are reasonable grounds, such as illness or difficulty obtaining relevant documents.
5. Appoint an impartial appeal manager
Where possible, the appeal should be handled by a manager who was not previously involved in the decision and who has sufficient authority to determine the outcome.
In smaller organisations, complete separation may not be practical. The employer should still take reasonable steps to make the process impartial, potentially by using an independent senior manager or external reviewer.
6. Decide whether further investigation is needed
The appeal manager should consider whether the existing records are sufficient or whether additional evidence is required.
A fair appeal is not necessarily a full reinvestigation in every case. The appropriate scope depends on the grounds raised, the original process and the nature of the complaint.
7. Allow the employee to explain the appeal
Arrange an appeal meeting where appropriate and give reasonable notice of the arrangements.
Workers have a statutory right to be accompanied at grievance appeal meetings covered by the relevant provisions of the Employment Relations Act 1999. The statutory right generally allows a companion who is a fellow worker, an eligible trade union representative or a qualifying trade union official.
The employer should explain the process and allow the employee a reasonable opportunity to present their concerns.
8. Communicate a reasoned written decision
The outcome should identify the issues considered, explain the decision and state any action the employer intends to take.
Depending on the findings, the appeal may be upheld, partially upheld or rejected. The employer may also decide that further investigation or another appropriate step is needed.
The decision should be communicated in writing without unreasonable delay.
9. Keep a clear record
Maintain appropriate records of the appeal, evidence considered, meetings, decisions and reasons.
Access to grievance records should be limited appropriately, with personal information handled in accordance with applicable data protection requirements.
10. Train managers and review the policy
Managers should understand how to distinguish a genuine appeal ground from a repeated complaint that adds no new issue, while remaining alert to important concerns that were not properly addressed.
Review the policy periodically and after significant changes in law, guidance or workplace practice.
6. When Can an Employer Reject a Grievance Appeal?
An employer may be able to reject an appeal that does not identify a meaningful challenge to the original outcome, depending on the policy and circumstances. However, rejection should not be automatic simply because the employee is unhappy or has not used the employer’s preferred wording.
The following situations require careful handling.
A. The appeal is late
If the appeal arrives after the policy deadline, the employer should check the reason for the delay and whether an extension is appropriate.
A late appeal does not automatically mean that the employee has lost every legal right relating to the underlying grievance.
B. The appeal repeats the original complaint
An employee may restate the same concerns without identifying a specific error or additional issue.
The employer can ask for clarification and assess whether the appeal genuinely challenges the outcome. If the policy permits a decision based on the existing material, the employer should still ensure that the relevant concerns have been considered fairly.
C. The appeal does not provide enough detail
An employer may request further information where the grounds are unclear.
It is usually better to give the employee a reasonable opportunity to clarify the appeal than to reject it immediately because it does not follow a particular format.
D. The employee provides no new evidence
New evidence is only one possible ground of appeal. An employee may reasonably challenge an outcome because the original findings were wrong or the procedure was unfair, even without producing additional documents.
Therefore, a policy that requires new evidence in every appeal may be unnecessarily restrictive.
E. The employee raises a new but relevant issue
A new concern may fall outside the scope of the original grievance. The employer should decide whether it belongs within the appeal, requires a separate grievance or needs another appropriate process.
The decision should depend on the substance of the concern, not merely the label used by the employee.
7. What Are the Risks of an Overly Restrictive Grievance Appeal Policy?
Limiting appeals too aggressively may appear efficient in the short term but can create problems later.
Increased employment tribunal risk
A poorly handled grievance may become relevant to an employment tribunal claim, depending on the underlying facts and legal cause of action.
An internal appeal policy cannot remove statutory rights. Failure to follow the Acas Code may also affect an award where the Code is relevant and the statutory conditions for an adjustment are met.
Reduced employee confidence
If employees believe an appeal will be rejected on a technicality, they may lose confidence in the grievance process.
A fair appeal procedure can help demonstrate that the employer takes complaints seriously and is willing to correct mistakes.
More unresolved workplace conflict
A complaint that remains unresolved can affect working relationships, attendance, retention and morale.
A properly conducted appeal may identify a misunderstanding or procedural failure before the dispute becomes more serious.
Inconsistent management decisions
Without clear grounds and guidance, different managers may deal with similar appeals in different ways.
A structured policy can improve consistency while retaining flexibility to account for the facts of each case.
Contractual and reputational consequences
Where an employer fails to follow a grievance procedure that forms part of the employment contract, a contractual dispute may arise.
Poor handling of workplace complaints may also affect employee trust and the organisation’s reputation as an employer.
8. How Employees Can Challenge an Unfair Restriction on Their Appeal
Employees who believe their employer has unfairly restricted a grievance appeal can take practical steps.
- Read the grievance policy. Check the stated grounds, deadline, recipient and appeal process.
- Explain the challenge in writing. Identify the specific decision or procedural problem and explain why it matters.
- Refer to the relevant Acas guidance. Explain why the concern should be considered as part of a fair appeal.
- Ask for clarification. If the employer refuses the appeal, request the reason and the policy provision relied upon.
- Keep relevant records. Retain the grievance, outcome letter, appeal correspondence and supporting evidence.
- Seek advice where necessary. A trade union representative, employment adviser or solicitor may help assess the available options.
Employees should not assume that an internal grievance appeal pauses an employment tribunal limitation period. Time limits vary according to the type of claim, and early advice is important where a deadline may be approaching.
Official guidance: GOV.UK — Appealing a grievance decision.
9. A Sample Grievance Appeal Policy Clause for UK Employers
The following is a starting point for a workplace policy, not a substitute for legal review.
Grounds for appeal
“An employee who remains dissatisfied with a formal grievance outcome may submit an appeal in accordance with this procedure. The appeal should be made in writing within the period specified in the grievance outcome letter or applicable policy.
An appeal may identify one or more concerns, including that the decision was incorrect or unreasonable, relevant evidence was not considered, new evidence has become available, the investigation or procedure was unfair, or the outcome did not adequately address the grievance. These examples are not exhaustive.
The employee should explain the reasons for the appeal, identify any relevant supporting evidence and state what outcome they would like the employer to consider.
The employer will review the appeal fairly and impartially. Where possible, it will be considered by a manager who has not previously been involved in the grievance decision. The employer may conduct further investigation where necessary and will communicate the appeal outcome in writing without unreasonable delay.
Where an appeal is submitted outside the applicable time limit, the employer will consider the circumstances and whether an extension is appropriate. Nothing in this procedure is intended to remove or restrict any statutory right.”
Employers should adapt the clause to their organisational structure, existing procedures, contractual commitments and the particular legal issues that may arise.
10. How Employers Can Plan and Implement the Policy
A good grievance appeal policy should be supported by a practical implementation plan.
Stage 1: Audit the existing procedure
Review the current grievance policy, employment contracts, staff handbook and any separate policies dealing with bullying, harassment, discrimination or whistleblowing.
Identify wording that could prevent legitimate appeals from being considered.
Stage 2: Consult HR and relevant managers
Ask the people who handle grievances to identify recurring problems, such as unclear deadlines, conflicts of interest or inconsistent decisions.
Where appropriate, involve employee representatives or recognised trade unions in policy development.
Stage 3: Define the process and responsibilities
Specify who receives an appeal, who investigates it, who makes the decision and who communicates the outcome.
Include arrangements for smaller workplaces where an entirely independent manager may not be available.
Stage 4: Train decision-makers
Provide practical examples of appeal grounds and explain how to assess evidence, procedural fairness, conflicts of interest and reasonable requests for additional time.
Training should emphasise that the purpose of an appeal is to review the original decision fairly, not simply to defend it.
Stage 5: Monitor and improve
Track issues such as appeal outcomes, delays, recurring procedural errors and complaints about the process.
Use these findings to improve training and policy wording. Monitoring should be proportionate and should respect employee confidentiality and data protection obligations.
11. Frequently Asked Questions
Can an employer limit grievance appeals to specific grounds under UK law?
An employer can define recognised grounds and set reasonable procedural requirements. However, it should avoid an inflexible list that prevents legitimate challenges to an incorrect outcome or an unfair procedure. The policy should be consistent with applicable law, contractual obligations and relevant Acas guidance.
Is an employee legally entitled to appeal every grievance decision?
The Acas Code states that employees should be allowed to appeal where they feel their grievance has not been satisfactorily resolved. Employers should provide an appropriate appeal process. The precise legal consequences of a particular refusal depend on the facts, applicable law and the employer’s procedures.
Can a grievance appeal be rejected because the employee has no new evidence?
Not automatically. An employee may challenge the original findings, the fairness of the investigation or the adequacy of the outcome without presenting new evidence. New evidence is only one recognised reason for an appeal.
Can an employer impose a five-day grievance appeal deadline?
An employer can set a reasonable deadline in its policy. Acas recommends five working days from receiving the outcome as an appropriate period, but this is guidance rather than a universal statutory deadline. Employers should consider reasonable requests for extensions where appropriate.
Does a grievance appeal have to be heard by a different manager?
Acas says appeals should, wherever possible, be handled by a manager who has not previously been involved. Where that is impractical, the employer should take reasonable steps to ensure the review is impartial.
Can an employer refuse an appeal because it repeats the original grievance?
The employer can assess whether the appeal identifies a meaningful challenge, but it should not reject it merely because the employee restates a concern. The appeal may still challenge the original reasoning or explain why the outcome did not resolve the issue.
Can an employee take legal action after an unsuccessful grievance appeal?
Depending on the facts and the legal claim, an employee may be able to pursue an external remedy even after an unsuccessful appeal—or without completing an internal appeal. Employment tribunal time limits can be strict, and an internal grievance process does not generally stop those deadlines from running.
Does the Acas Code apply throughout the UK?
The Acas Code applies in Great Britain: England, Wales and Scotland. Northern Ireland has a separate employment relations framework, including guidance from the Labour Relations Agency.
Conclusion: The Right Balance Between Clear Grounds and Fair Appeals
Employers can make grievance appeals more manageable by defining recognised grounds, setting reasonable deadlines, explaining submission requirements and appointing impartial decision-makers.
But a grievance appeal policy should not become a barrier that prevents employees from challenging an incorrect decision or an unfair process.
The strongest approach is to provide a clear list of common appeal grounds while allowing other relevant concerns to be considered. Employers should assess each appeal on its facts, investigate further where necessary, provide a reasoned written outcome and retain appropriate records.
For employees, understanding the appeal procedure can make it easier to explain what went wrong and what action may resolve the issue.
For employers, a fair and consistently applied policy can support better workplace relationships, more defensible decisions and a lower risk of avoidable disputes.
If an organisation is planning to restrict grievance appeals or revise its employment policies, it should review the proposed wording against the current Acas Code, GOV.UK guidance, contractual commitments and any relevant statutory rights before introducing the change.