ACAS early conciliation: how it works and what to expect

Before you can bring almost any employment tribunal claim you must first notify ACAS and go through early conciliation. It is a legal requirement, not an optional step, and getting the timing wrong is one of the few mistakes that can end a good claim before it starts. This guide explains what actually happens, how long it takes, and what the certificate at the end is for.

What early conciliation is

ACAS is the Advisory, Conciliation and Arbitration Service. It is independent of both you and your employer, and it is free.

Early conciliation gives both sides a chance to settle before a claim is lodged. A conciliator speaks to each side separately, passes offers back and forth, and records any agreement. They do not judge who is right, they do not give either side legal advice, and they cannot force anyone to settle.

Notifying ACAS is compulsory. Taking part in the conciliation itself is not. You can tell ACAS you do not want to conciliate and still get the certificate you need.

How the process runs

• You notify ACAS, online or by phone, giving your details and your employer's. This is when the clock stops on your tribunal deadline.
• A conciliator makes contact, usually within a few days, to understand what has happened and what you want.
• They approach your employer. Your employer does not have to engage. If they refuse, conciliation ends and you move on to a claim.
• Offers pass between the parties, sometimes over several weeks.
• It ends either with an agreement recorded on a COT3 form, or with ACAS issuing an early conciliation certificate.

The effect on your time limit

This is the part worth reading twice. Most tribunal claims must be started within three months less one day of the act you are complaining about, usually the dismissal date.

Notifying ACAS pauses that clock. The pause runs from the day after you notify until the day you receive the certificate. Once the certificate is issued you get the remaining balance of your three months back, and if less than one month is left you get a full month from the date of the certificate.

The practical rule is simple. Notify ACAS early rather than late. It costs nothing, it does not commit you to anything, and it buys back time. Waiting until week eleven to notify leaves almost no margin for error.

What a COT3 is

If you settle through ACAS, the agreement is recorded on a COT3. It is legally binding and, like a settlement agreement, it stops you bringing the claims it covers.

Unlike a settlement agreement, a COT3 does not require you to take independent legal advice, which is exactly why it is worth taking some anyway. The wording is usually drafted by your employer's side, it is often broader than it needs to be, and once signed it is very hard to reopen. Check what claims are covered, when payment is due, what the tax treatment is, and whether a reference and confidentiality wording are included.

Getting the most out of conciliation

Decide what a good outcome looks like before the conciliator calls. Money is the obvious one, but a reference, an agreed leaving statement, removal of a warning from your file, or an apology can matter more and often cost your employer less.

Be realistic about value. Conciliators pass on offers, they do not talk your employer up. If you cannot explain how you arrived at your figure, expect it to be discounted.

Do not treat conciliation as your only route. Preparing the claim in parallel keeps the pressure on and means you are not scrambling if talks fail.

When ACAS is not enough

Early conciliation works well where the dispute is mostly about money and both sides want it over. It works less well where your employer denies everything, where the claim involves discrimination or whistleblowing and the value is uncapped, or where you need documents from the employer to prove what happened.

In those cases the conciliation stage is mainly a formality on the way to a claim, and the useful work is preparing the claim properly. A short conversation with a specialist employment solicitor before you notify ACAS will tell you which of those situations you are in, and what number to have in mind when the conciliator rings.