Mediation is a conversation, held with help, about how you and someone else at work carry on from here. A neutral mediator sits between you and the other person, hears both sides in private, then brings you together to agree what changes. It is voluntary, it is confidential, and it decides nothing on its own — you keep control of what you agree to. Employers increasingly offer it instead of a formal grievance, and sometimes that is the faster, better route. Sometimes it is the wrong tool entirely, and saying yes costs you ground you cannot get back. This guide sets out how to tell the difference.
Contents
- What workplace mediation is
- When mediation works
- When mediation is the wrong route
- Mediation compared with a grievance
- How the process works, step by step
- Confidentiality and what it means for you
- What you can agree to
- Your rights around mediation
- Mediation and legal time limits
- FAQs
- How the National Employees Union can help
What workplace mediation is
Mediation is a structured discussion led by an impartial third party. The mediator does not investigate, does not take evidence, and does not decide who was right. Their job is to help you and the other person understand each other and agree how you will work together in future.
That future focus is the defining feature. A grievance looks backwards and asks what happened. Mediation looks forwards and asks what changes. ACAS describes it as a way of mending working relationships rather than judging past behaviour.
The mediator may be an external professional, an ACAS mediator, or a trained internal colleague from another part of the organisation. Internal mediators must be genuinely independent of both parties. If the person mediating manages either of you, or has already formed a view, they are not neutral and you can say so.
When mediation works
Mediation works best where the relationship still matters and both people want it repaired. Typical situations include personality clashes between colleagues, breakdowns in communication with a line manager, disagreements about workload or working patterns, tension after a return from sick leave, and friction that has grown out of a misunderstanding rather than misconduct.
It also works well early. A disagreement that has run for three weeks is far easier to settle than one that has run for a year and produced a paper trail on both sides. Where your employer offers mediation at the first sign of trouble, that is usually a good sign about how they handle conflict.
Mediation can succeed after a formal process too. Where a grievance has been upheld in part and you still have to work with the same manager, mediation is often the only thing that makes the workplace liveable again.
When mediation is the wrong route
Mediation is not suitable for everything, and an employer who pushes it in the wrong situation may be avoiding an obligation.
Do not accept mediation as a substitute for a formal process where the complaint involves discrimination, harassment or sexual harassment, bullying that amounts to a pattern of conduct rather than a clash, whistleblowing or a protected disclosure, allegations of dishonesty or safety breaches, or anything that could lead to a disciplinary sanction against the other person.
These matters need findings of fact. Only a workplace investigation can produce those. Mediation, by design, makes no findings at all — so agreeing to it can leave serious conduct unrecorded and unaddressed.
The other clear limit is power. Mediation assumes two parties who can speak freely. If you fear the other person, or they control your shifts, your pay or your progression, say so before you agree. A good mediator will screen for this and stop the process.
Mediation compared with a grievance
The two routes answer different questions. This table sets out the practical differences.
| Mediation | Formal grievance | |
|---|---|---|
| Question asked | How do we work together from here? | What happened, and was it wrong? |
| Who decides | You and the other person | Your employer |
| Outcome | An agreement you both write | A decision, upheld or not |
| Findings of fact | None | Yes |
| Written record | Usually only the agreement | Full outcome letter |
| Confidential | Yes | No, forms part of the record |
| Right to be accompanied | No statutory right | Statutory right at the hearing |
| Typical timescale | One to three weeks | Four to twelve weeks |
| Appeal | None | Yes |
The absence of a written record cuts both ways. It lets people speak honestly. It also means that if the behaviour continues, you start again with nothing on file. Where you may need evidence later, put the complaint in writing first — our guide to writing a grievance letter shows how — and treat mediation as an addition, not a replacement.
How the process works, step by step
1. The offer
Either party, or HR, suggests mediation. You are told who the mediator is and asked whether you agree. You can ask to change the mediator at this point.
2. Separate meetings
The mediator meets each of you alone. You explain what has happened and what you want to change. Nothing you say here is passed on without your permission.
3. Your decision to continue
After the private meeting you decide whether to go on. If you withdraw, the mediator simply reports that mediation is not possible. No reasons are given.
4. The joint meeting
The mediator brings you together, agrees ground rules, and asks each person to speak without interruption. You can ask for a break at any time. Most joint meetings run for two to four hours.
5. The agreement
If you reach common ground, the mediator writes it down in plain terms. You both check it and sign. Copies usually go to no one else except, in summary form, to HR.
6. Review
Good mediation agreements set a review date, typically four to eight weeks later, to check the changes have held.
Confidentiality and what it means for you
Mediation is confidential. If no agreement is reached, what was said during the mediation cannot normally be used in a later grievance, disciplinary or tribunal claim. That protection is what allows both sides to be candid.
There are limits. A mediator will break confidentiality where there is a risk of serious harm, a safeguarding concern, or a criminal offence. Confidentiality also does not erase the underlying facts: you can still raise a formal grievance afterwards about the same events, provided you rely on evidence from outside the room.
Before you go in, agree with the mediator what may be shared with HR. A one-line note that mediation happened is normal. A summary of your position is not.
What you can agree to
Mediation agreements are practical, not legal. Common terms include changes to reporting lines, an agreed way of raising problems in future, revised handover or rota arrangements, an agreement on tone and language in meetings, a commitment to weekly check-ins, and a date to review it all.
Mediation agreements are not usually legally binding. They rely on goodwill. If a term matters enough to be enforceable, ask for it to be confirmed separately in writing by your employer, so it becomes a change to your working arrangements rather than a private promise.
What mediation cannot deliver is money, an apology you can enforce, a finding against anyone, or a sanction. If those are what you need, use the formal route.
Your rights around mediation
Mediation is voluntary. There is no statutory duty to take part, and refusing it is not misconduct. The ACAS Code of Practice on Disciplinary and Grievance Procedures encourages employers to consider mediation, but it does not require you to accept.
There is no statutory right to be accompanied at mediation. The right under section 10 of the Employment Relations Act 1999 applies to formal grievance and disciplinary hearings, not to mediation. You can still ask, and many mediators allow a supporter in the private sessions.
Refusing mediation should carry no penalty. If your employer delays your grievance, withdraws goodwill, or treats you differently because you declined, that is a separate concern. Where the treatment is serious enough to destroy trust and confidence, it can support a claim for constructive dismissal — though resigning is a high-risk step and you should take advice first.
Mediation and legal time limits
Mediation does not pause the clock on a tribunal claim. This is the most common and most costly mistake.
For most claims the time limit is three months minus one day from the act you are complaining about. From 1 October 2026 that limit rises to six months for most claims under the Employment Rights Act 2025, but the earlier limit still governs anything that happened before the change takes effect. Only notifying ACAS pauses the clock — see our step-by-step guide to ACAS Early Conciliation.
So if you are within weeks of a deadline, notify ACAS first and mediate second. The two are separate: ACAS cannot provide workplace mediation once early conciliation has started or a claim has been made.
FAQs
Is mediation at work compulsory in the UK?
No. Mediation is voluntary for both parties. You can decline at the outset or withdraw after the first private meeting, and you do not have to give a reason. Refusing mediation is not misconduct and should not affect your grievance.
Can I take someone with me to mediation?
There is no statutory right to be accompanied at mediation, because section 10 of the Employment Relations Act 1999 covers formal grievance and disciplinary hearings only. Many mediators will still agree to a supporter attending your private session. Ask before the day rather than on it.
Does mediation stop me raising a grievance later?
No. You can raise a formal grievance about the same events after mediation fails or breaks down. You cannot use what the other person said inside the mediation as evidence, so build the grievance on emails, notes and witnesses from outside the room.
Is a mediation agreement legally binding?
Usually not. It is a good-faith agreement about future working, not a contract. If a term is important, ask your employer to confirm it separately in writing so it forms part of your working arrangements.
Does mediation extend my employment tribunal time limit?
No. Only notifying ACAS of a potential claim pauses the clock. Mediation runs alongside your time limit and does not extend it, so notify ACAS before the deadline even if mediation is still going.
Can my employer make me mediate instead of investigating harassment?
No. Allegations of discrimination, harassment or misconduct need findings of fact, which mediation does not produce. Your employer should investigate. You can accept mediation as well, but not instead.
How the National Employees Union can help
Mediation is useful when it is the right tool and damaging when it is used to bury a serious complaint. Knowing which one you are being offered is the whole skill.
National Employees Union members get:
An assessment of whether mediation fits your situation, or whether the formal route protects you better
Help preparing what you want to say and what you want to change
A check on the mediator’s independence before you agree
Review of any draft mediation agreement before you sign it
Support with a formal grievance or disciplinary process if mediation fails
Advice on time limits and next steps, including tribunal deadlines
Time limits keep running while you mediate. Speak to us before you agree to anything.
Join the National Employees Union today
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Written by the National Employees Union team. Our reps are legally trained and support members through mediation and formal procedures across the UK. This guide is reviewed regularly and was last updated in August 2026. For advice on your specific situation, contact us.
