How to make a constructive dismissal claim

If your employer's conduct forced you to resign, you may have a constructive dismissal claim. This guide covers every step — from preserving your position to filing your ET1 and preparing for tribunal.

Do not affirm the breach

If your employer has fundamentally breached your contract, you must act quickly. Continuing to work for an extended period after the breach without protest may be taken as acceptance — known as "affirming the breach" — which can destroy your claim. Keep a record of the breach as soon as it happens and make clear (in writing) that you do not accept it.

Resign and state why

Your resignation letter must make clear that you are resigning in response to your employer's fundamental breach of contract. You do not need to use the phrase "constructive dismissal" — but you must reserve your right to bring a claim. Keep a copy. See our resignation letter template for exact wording.

Contact ACAS within 3 months

You have 3 months minus one day from your last day of employment to contact ACAS and start Early Conciliation. This is a legal requirement before you can file a tribunal claim. The clock starts from your resignation date. ACAS Early Conciliation pauses the time limit while talks take place — but do not wait.

ACAS Early Conciliation

ACAS will attempt to help you and your employer reach a settlement without going to tribunal. This is free and confidential. If conciliation fails (or your employer refuses), ACAS issues a certificate that lets you file your ET1 claim. The conciliation period is up to 6 weeks.

File your ET1 claim form

Using your ACAS certificate number, submit your ET1 online via the Government's employment tribunal portal. Your ET1 must set out the facts of your claim clearly: the breach, when it happened, that you resigned because of it, and the losses you are claiming. This is your primary legal document — it cannot easily be changed later.

After your ET1 is accepted, your employer files an ET3 response. The tribunal will schedule a preliminary and/or full hearing. You will need an evidence bundle (documents, emails, letters), a witness statement, and a schedule of loss setting out your financial claim. Start gathering evidence now.

How long do I have to claim constructive dismissal?

You must contact ACAS to start Early Conciliation within 3 months minus one day of your last day of employment. Missing this deadline usually means your claim is permanently time-barred. The tribunal has discretion to extend only where it was "not reasonably practicable" to meet the original deadline — which is very rarely granted.

Do I need 2 years of service to claim constructive dismissal?

Yes — for an ordinary unfair dismissal claim, you need 2 years' continuous service with the same employer. However, if your constructive dismissal also involved discrimination, whistleblowing, pregnancy/maternity, asserting a statutory right, or trade union activities, there is no qualifying period. From April 2027, the qualifying period drops to 6 months under the Employment Rights Act 2025.

Can I claim constructive dismissal if I resigned without notice?

Yes. If your employer's conduct was a repudiatory breach, you are entitled to resign without notice (known as "accepting the repudiation"). This does not harm your claim. You should state in your resignation letter that you resign with immediate effect because of the breach.

How much can I claim for constructive dismissal?

A constructive dismissal award is made up of a Basic Award (based on age, length of service and weekly pay, capped at £643/week from April 2024) and a Compensatory Award (for financial losses, capped at the lower of £115,115 or 52 weeks' gross pay). If discrimination is also proven, there is no cap on the compensatory element.

Is constructive dismissal hard to prove?

Yes — constructive dismissal is one of the harder claims to win at tribunal. You must prove (1) there was a fundamental breach of contract, (2) you resigned because of it, and (3) you did not affirm the breach. Tribunals scrutinise whether the conduct was truly fundamental rather than merely unreasonable, and whether the resignation was genuinely caused by the breach.

Do I need a solicitor to claim constructive dismissal?

No. Around 59% of tribunal claimants represent themselves. The tribunal process is designed to be accessible without legal representation. Start My Claim guides you through your ET1 form, evidence bundle, witness statement, and hearing preparation — at a fraction of the cost of a solicitor.

What evidence do I need for a constructive dismissal claim?

Key evidence includes: written records of the breach (emails, letters, performance reviews, written warnings), any grievances you raised and the employer's response, your resignation letter, payslips and contract, records of financial losses (job applications, rejection letters), and witness evidence if colleagues observed the conduct. Start gathering this immediately after resignation.

How to make a constructive dismissal claim in the UK

A step-by-step guide to making a constructive dismissal claim at employment tribunal in the UK — from preserving your position to filing your ET1.

How to make a constructive dismissal claim

Last updated: April 2026 · Employment Rights Act 2025 provisions included

Time limit from last day of work

Service required (dropping to 6 months Apr 2027)

To file your tribunal claim

To start your claim with Start My Claim

The 6 steps to a constructive dismissal claim

The 3-month deadline is strict

You must contact ACAS within

of your last day of employment. Employment tribunals almost never grant extensions. If you miss the deadline, you lose your right to claim — even if your claim would have succeeded.

Estimate your compensation

A constructive dismissal award has two parts: a Basic Award and a Compensatory Award. Use the calculator below for an indicative figure.

What you need to prove

Constructive dismissal is one of the harder claims to win. The burden of proof is on you — the claimant — to show all three of the following:

1. Fundamental breach

Your employer breached a core term of your contract — not just acted unreasonably, but breached a fundamental obligation such as pay, safety, or the implied duty of trust and confidence.

2. You resigned because of it

The breach was the effective cause of your resignation. If you resigned for other reasons — or delayed so long that the tribunal infers you accepted the breach — your claim will fail.

3. You did not affirm the breach

You must have acted promptly. Continuing to work for an extended period after the breach without protesting is likely to be treated as acceptance, ending your right to resign and claim.

Evidence to gather immediately

Start collecting evidence before you resign if possible — and certainly immediately after. You will need this for your ET1, your evidence bundle, and your witness statement.

Start building your claim today

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Frequently asked questions

What is constructive dismissal?

The legal definition, what counts as a fundamental breach, and how tribunals assess claims.

Resignation letter template

A template resignation letter that reserves your right to bring a constructive dismissal claim.

Already resigned — can I still claim?

What to do if you have already resigned and are wondering whether you can still bring a claim.

ACAS early conciliation guide

How ACAS Early Conciliation works and why you must complete it before filing your ET1.

How to complete the ET1 form

A step-by-step guide to completing and submitting the ET1 employment tribunal claim form.

Writing your witness statement

How to write a compelling witness statement for your employment tribunal hearing.