Acas early conciliation explained

What is Acas early conciliation?

Acas early conciliation is a compulsory step before most employment tribunal claims. You notify Acas, who then offer to help you and your employer reach a settlement without a hearing. It usually runs for up to six weeks and pauses the tribunal time limit while it is live. Many settlement agreements are reached during, or shortly after, this process.

You start the process by submitting an early conciliation notification to Acas, either online or by phone. Acas then contacts you and, if you want to proceed, contacts your employer to see whether both sides are open to a conciliated settlement. A conciliator does not decide who is right; they help both sides explore whether a figure can be agreed without going to a hearing.

When is early conciliation compulsory?

With very limited exceptions, you cannot issue an employment tribunal claim without first contacting Acas. You must either complete early conciliation, or Acas must have issued you an early conciliation certificate confirming that conciliation did not lead to a settlement, before a tribunal will accept your claim.

This applies across almost every claim type that goes to an employment tribunal, from unfair dismissal and redundancy pay disputes to discrimination and whistleblowing claims. Missing this step is a technical but real trap: a claim form issued without a valid certificate number can be rejected outright.

How does early conciliation pause the tribunal time limit?

The clock on your time limit, ordinarily three months less one day from the effective date of termination for most claims, stops on the day you notify Acas and starts running again the day after the conciliation period ends. If the limit would otherwise expire during, or within a month of, the conciliation period, it is extended so you still get a full month afterwards to issue your claim.

In practice this means the deadline to actually issue a tribunal claim is rarely a single fixed date you can calculate in your head; it depends on exactly when you notified Acas and when the conciliation period ended. If you are close to a deadline, get the exact date checked rather than estimate it.

Is the 10-day Acas Code period part of early conciliation?

No, and this is a common point of confusion. The 10 calendar days often mentioned alongside a settlement agreement offer comes from the separate Acas Code of Practice on settlement agreements, which gives guidance that 10 calendar days is a reasonable period for an employee to consider a written offer and take advice. That is guidance, not a legal minimum, and it is a different thing from the up-to-six-week early conciliation window described above.

See our guide on what is a settlement agreement for how that 10-day guidance applies once you actually have an offer in front of you.

Is the time limit changing?

The three-months-less-one-day time limit described above is the current rule. The Employment Rights Act 2025 provides for this limit to be extended once the relevant provision commences, which would give employees longer to notify Acas and issue a claim. Until that provision is in force, the existing time limit, and the pausing effect of early conciliation on it, continues to apply.

How do settlement agreements and COT3s relate to early conciliation?

A settlement reached during, or shortly after, early conciliation is usually recorded on a form called a COT3. A COT3 has the same binding effect as a settlement agreement, waiving the claims it lists, but it is reached through Acas rather than the section 203 route, and it does not need a solicitor's certificate the way a settlement agreement does. See the glossary entry on COT3 for how the two forms compare.

If a case moves past early conciliation, whether because no early settlement is reached or because it proceeds towards a hearing, any later settlement is more often recorded in a conventional settlement agreement instead, which does require independent legal advice under section 203 of the Employment Rights Act 1996.

Frequently asked questions