When an employee raises a grievance, you must follow a fair procedure: acknowledge it in writing, investigate, hold a formal grievance meeting, give the employee the outcome in writing, and offer a right of appeal. Failing to deal with a grievance — or dealing with it poorly — can convert a manageable complaint into a constructive dismissal claim. The ACAS Code of Practice on Disciplinary and Grievance Procedures sets the standard.
What is a grievance?
A grievance is a concern, complaint, or problem that an employee raises with their employer. It might relate to:
- How they are being treated by a manager or colleague (including bullying or harassment)
- Their terms and conditions of employment
- The working environment or working practices
- A disagreement about how a policy has been applied to them
- A complaint about discrimination
Employees are entitled to raise grievances without suffering any detriment for doing so. Penalising an employee for raising a grievance — for example, by reducing their hours or giving them a poor appraisal — can give rise to a victimisation claim under the Equality Act 2010.
Step 1: Acknowledge the grievance in writing
When a grievance is raised (whether verbally or in writing), acknowledge it promptly — ideally within 2 to 5 working days. Your acknowledgement should:
- Confirm you have received the grievance
- Name the person who will investigate and/or hear the grievance
- Give an indicative timeline
Do not dismiss or downplay the grievance at this stage, even if you think it is unfounded. Every grievance deserves a fair hearing.
Step 2: Investigate
Before holding a formal meeting, investigate the grievance. This may involve:
- Speaking to relevant witnesses
- Reviewing documents, emails, or records
- Obtaining any other relevant evidence
The investigation should be proportionate to the seriousness of the complaint. A complaint about a minor administrative error needs less investigation than an allegation of harassment.
Step 3: Hold a formal grievance meeting
Invite the employee to a formal grievance meeting in writing. The letter should:
- Set out the date, time, and location
- State that they can bring a companion (a trade union rep or workplace colleague)
- Give them enough notice to prepare (at least 48 hours)
At the meeting:
- Let the employee explain their grievance fully without interruption
- Ask clarifying questions
- Do not make any decisions or commitments at the meeting
- Adjourn, consider the matter, then give the outcome separately
Step 4: Give the outcome in writing
After the meeting, write to the employee with:
- A summary of the grievance raised
- What the investigation found
- The decision and the reasoning
- Any action being taken (or why no action is being taken)
- The right of appeal, to whom, and within what timescale
Be specific. Vague outcomes ("we investigated and found no evidence of wrongdoing") without explanation are frustrating for employees and difficult to defend at tribunal.
Step 5: Conduct the appeal
If the employee appeals, the appeal should be heard by a different manager where possible. The appeal is a genuine reconsideration — not just a review of whether the process was followed. After the appeal, write to the employee with the outcome. The appeal decision is final in the internal process.
What if a grievance is raised during a disciplinary?
This is one of the most common complications. An employee facing disciplinary action sometimes raises a grievance mid-process — often as a tactic to pause the disciplinary.
ACAS guidance says you should consider whether the grievance is related to the disciplinary matter. If it is, you can pause the disciplinary to deal with the grievance, or (where appropriate) deal with both at the same time. If the grievance is unrelated, you can continue both processes in parallel.
Do not automatically halt a disciplinary simply because a grievance has been raised. Document your reasoning.
Grievance process timeline
| Stage | Suggested timescale | |---|---| | Acknowledge the grievance | Within 2 to 5 working days | | Complete investigation | 2 to 4 weeks (depending on complexity) | | Hold grievance meeting | Within the investigation period | | Issue written outcome | Within 5 working days of the meeting | | Appeal hearing | Within 2 weeks of the appeal being lodged | | Appeal outcome | Within 5 working days of the appeal |
Frequently asked questions
Does every employer need a written grievance procedure? Under the Employment Rights Act 1996, employers must provide employees with information about the grievance procedure. A written procedure in the staff handbook or contract is the standard way to do this. Not having one does not prevent employees raising grievances — it just means the employer is less prepared.
Can an employee raise a grievance anonymously? An employee can ask for their identity to be kept confidential. However, if the grievance involves allegations against a named individual, that person has the right to know what is alleged against them in order to respond. Full anonymity is rarely achievable in a small business.
What if the grievance is about the owner or most senior manager? If the grievance is about the person who would normally hear it, another senior person (or an external HR consultant) should handle the process to ensure impartiality.
Can an employee raise a grievance after they have left? Yes — a former employee can raise a grievance. You are not obliged to follow the same internal procedure, but ACAS recommends responding and investigating where possible. Ignoring a post-employment grievance can be relevant in subsequent tribunal proceedings.
What is the difference between a grievance and a complaint to ACAS? A grievance is an internal complaint to the employer. ACAS early conciliation is an external process that must be attempted before a claimant can bring a tribunal claim. Raising an internal grievance first is not a legal requirement before going to ACAS — but a tribunal will consider whether the employee gave the employer a chance to resolve the matter.
