Acas early conciliation is the step you must start before most employment tribunal claims in Great Britain: you notify Acas, and a conciliator tries to help you and your employer reach a legally binding agreement. It can last up to 12 weeks, the tribunal time limit is paused while it runs, and you get a certificate number you need to make a claim.
Whether you're an employee thinking about a claim or a small employer who's just had a call from Acas, early conciliation is the gateway to the tribunal system. Here's how it works, based on Acas and GOV.UK guidance.
When early conciliation fits
Acas is clear that early conciliation isn't the first step. It's only for people considering a tribunal claim. Before that, it's usually quicker to try to solve things informally, raise a formal grievance, or appeal a disciplinary or grievance outcome. A tribunal judge will usually expect you to show that you tried to resolve the dispute yourself, and if you didn't, it could affect your compensation. But raising the problem with your employer first doesn't stop the clock on your time limit.
The time limits changed on 1 October 2026
| When the problem happened | Time limit for most claims |
|---|---|
| Before 1 October 2026 | 3 months minus 1 day |
| On or after 1 October 2026 | 6 months minus 1 day |
| Breach of contract claims in Scotland | 6 months minus 1 day only for problems on or after 9 November 2026 |
| Interim relief after certain dismissals | 7 days, and you might not need to notify Acas |
Acas gives worked examples: a pay problem on 30 September 2026 has a limit ending at 11:59pm on 29 December 2026, while one on 1 October 2026 runs to 11:59pm on 31 March 2027. For unfair dismissal, the clock usually starts on the last day of the notice period, or the dismissal date if no notice was given. For discrimination, it runs from the most recent incident in the claim. You have to notify Acas within your time limit, and it's up to you to do it in time.
How the process works, step by step
- You notify Acas that you intend to make a tribunal claim, and Acas asks whether you want early conciliation.
- If you say no, Acas issues a certificate so you can go to tribunal.
- If you say yes, you get a reference number and Acas reviews your details, calling you if it needs more.
- Your case is assigned to a conciliator, who talks to you about the dispute and the outcome you want.
- With your agreement, the conciliator contacts your employer to see if they'll take part.
- If both sides talk, the conciliator goes between you to look for an agreement, for up to 12 weeks.
- If you agree, it's written up as a COT3; if not, you get a certificate with the number you need for form ET1.
If Acas doesn't hear back from you, it sends the certificate anyway. And if you notified Acas within your time limit, you'll have at least 1 month from receiving the certificate to make your claim.
What a conciliator will and won't do
| Will | Won't |
|---|---|
| Explain their role and the process | Take sides: Acas is impartial |
| Explore how you could settle without a tribunal | Judge how your case would turn out |
| Discuss how tribunals have treated similar cases | Advise whether your claim is exempt from early conciliation |
For an opinion on your chances, you'll need legal advice. Acas also isn't part of the tribunal service and won't discuss your case with it.
The COT3: binding before you sign
Here's the detail that catches both sides out. Once you and the other side agree terms, you're bound by them, even before the COT3 is signed. A settled case can't go to tribunal, even if a claim was already made: it's closed with no hearing. If the employer then doesn't pay what was agreed, the free government enforcement and naming scheme can be used for a COT3. The employer gets a warning notice giving them 28 days to pay, and if they still don't, they're fined and the employee can go to court.
Plenty of disputes end with a settlement agreement, and our settlement agreements guide shows how those work.
What employers should know
If an employee has notified Acas, you'll be offered early conciliation if they agree. You don't have to take part, but Acas points out the advantages: it can save time and cost, and the dispute stays confidential, whereas a tribunal is a public hearing. The employee's time limit is paused during the talks. You can also request early conciliation yourself if you think a dispute could lead to a claim. One catch: when the employer is the one to notify Acas, the tribunal time limit isn't put on hold.
Talks can continue through Acas right up to a tribunal judgement, which is called conciliation rather than early conciliation, usually with the same conciliator. If you're growing a team without in-house HR, my guide on choosing HR advice for a growing business is worth a read, along with these tips to improve employee management before disputes start.
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My verdict
Early conciliation is one of the most useful tools in UK employment law. For employees, the big news is the longer 6-month window for problems from 1 October 2026, but don't leave it late. For employers, take the call seriously, because agreed terms bind you before anyone signs. Settling privately beats a public hearing for most small businesses.
Employees can also ask for flexible working from day one, which our flexible working request guide explains.
Frequently asked questions
What is Acas early conciliation?
A voluntary process where an Acas conciliator helps you and your employer try to settle a dispute before an employment tribunal claim.
Is early conciliation compulsory?
You must notify Acas before most tribunal claims, but taking part in talks is voluntary for both sides.
How long does early conciliation take?
It can last up to 12 weeks.
Does early conciliation stop the time limit?
Yes, when the employee notifies Acas the time limit is paused. It isn't paused if the employer is the one who notifies Acas.
What is the time limit for an employment tribunal claim?
For most claims, 6 months minus 1 day if the problem happened on or after 1 October 2026, and 3 months minus 1 day if it happened before.
What is a COT3?
The legally binding conciliation agreement Acas writes up when both sides settle. You're bound by agreed terms even before signing.
