The Disciplinary Appeal Process Explained

When an employee is given a disciplinary warning or dismissed, the appeal is their opportunity to ask for the decision to be looked at again. For the employer, it is the last chance to correct any mistakes before a tribunal does. Many employers, particularly smaller ones, have never run a disciplinary appeal and are unsure what the process involves.

This post explains the disciplinary appeal process step by step, what each party can expect, and what a well-run appeal looks like. It is written primarily for employers and managers, but it is also relevant for employees who are deciding whether to appeal.

Why the appeal stage matters

The Acas Code of Practice on disciplinary and grievance procedures says that employees should be allowed to appeal against any formal decision made under the procedure. In practice the appeal is often the more consequential stage. It is the employer's final internal word, it will almost certainly be disclosed in any later tribunal claim, and its reasoning, or the lack of it, will be examined closely.

Where an employee has been dismissed, the appeal forms part of the dismissal process. A tribunal considering whether the dismissal was fair will look at the whole procedure, including the appeal. A thorough appeal can sometimes cure defects in the original hearing. A careless one can turn a sound dismissal into an unfair one.

The stakes are rising. From 1 January 2027 the qualifying period for ordinary unfair dismissal claims falls from two years to six months, and the cap on compensation is removed. Most tribunal claims are also due to have a six-month time limit from 1 October 2026, rather than three months.

Starting an appeal: grounds and deadlines

An appeal begins when the employee tells the employer, in writing, that they wish to appeal and why. The Acas Code does not set a deadline, but most procedures allow five to ten working days from receipt of the outcome letter. Employers should apply their own procedure consistently and think carefully before refusing a late appeal on a technicality.

The grounds of appeal commonly fall into five categories. The employee may say the procedure was unfair, for example because of inadequate notice, missing evidence or no chance to be accompanied. They may say the finding was wrong and not supported by the evidence. They may say the sanction was too harsh in the circumstances, or inconsistent with how others were treated. They may have new evidence that was not available at the original hearing. Or they may allege bias, including that the decision-maker had already made up their mind.

The employer should acknowledge the appeal promptly, confirm who will hear it and explain the next steps.

Who hears the appeal

The appeal should be heard by someone who was not involved in the original decision and who is, where possible, more senior than the person who made it. The Acas Code recommends that, wherever possible, the appeal is dealt with by a manager who has not previously been involved in the case.

Smaller organisations often find this difficult. The options are a director from another part of the business, a board member or trustee, or an independent external chair. An independent chair also has the advantage of being able to confirm, at the start of the meeting, that they are not acting for either party.

Before the appeal hearing

The employee should be invited to the hearing in writing, with reasonable notice. The invitation should give the date, time and format, confirm who will hear the appeal, and remind the employee of their right to be accompanied by a trade union representative or a work colleague. That right applies to appeals against formal warnings and dismissals as well as to original hearings.

The person hearing the appeal should have a full bundle: the disciplinary invitation, the investigation report and evidence, the notes of the original hearing, the outcome letter, the policy and the grounds of appeal. The employee should have the same documents, plus a fair chance to see anything new. Sharing papers in advance avoids arguments about procedural fairness on the day.

The chair should also decide what kind of appeal this is. A review asks whether the original decision was reasonable and the procedure fair, and examines the earlier findings. A rehearing looks at the case afresh. Most procedures provide for a review, and that is usually sufficient, but where the original process was seriously flawed, a fuller rehearing may be the only way to put things right. Whatever the approach, the employee should be told which it is.

At the appeal hearing: what actually happens

The chair opens by introducing themselves, explaining the purpose and format of the hearing, and confirming their independence from the original decision.

The employee is invited to present their appeal: what they say went wrong, and what they want as a remedy. Their companion may support them but should not replace their voice.

The chair asks questions to understand the grounds and test the evidence. Good questioning is not adversarial. It is designed to find the real points of dispute.

The manager who took the original decision, or another management representative, responds to the grounds and explains the reasoning. This is a defence of the process and the decision, not a rerun of the original hearing.

The employee is then given the final word. The hearing closes and is adjourned, and the chair does not announce a decision on the day. If new information or a missing witness needs to be followed up, the chair can adjourn to do so, as a focused step rather than a wide reinvestigation.

The outcome

The chair may uphold the appeal, partly uphold it, or dismiss it. Where an appeal is upheld, the possible remedies include overturning the finding, reducing the sanction, removing a warning from the file or, after a dismissal, reinstating the employee. Unless the procedure clearly says otherwise, an appeal should not be used to impose a harsher sanction than the original decision, and employees should be told in advance if the procedure allows this.

The outcome should be confirmed in writing, without unreasonable delay, and within five to ten working days is good practice. The letter should address each ground of appeal in turn and give reasons. A letter that says the appeal has been considered and the original decision is confirmed does not do enough. The letter should also state that the decision is final, and what the employee can do if they remain dissatisfied.

An appeal outcome does not usually pause the tribunal clock. The time limit for a dismissal claim generally runs from the date the dismissal took effect, not from the appeal outcome, so employees who are considering a claim should be aware of early conciliation through Acas and act promptly.

The final word

A disciplinary appeal is not a formality. It is the employer's best chance to show that its process was fair, and the employee's best chance to have a mistake corrected without going to a tribunal. Getting it right needs an independent chair, a fair structure, a genuine reconsideration of the grounds, and a written outcome that explains the reasoning. The cost of doing it properly is modest. The cost of doing it badly is not.