Constructive dismissal is when you resign because your employer has seriously breached your employment contract. The legal term is constructive unfair dismissal.

These claims are hard. The burden is entirely on you. You must prove the breach, prove it caused your resignation, and prove you did not accept it by delay. Meanwhile resignation ends your income immediately, and with it your statutory sick pay, private medical cover and pension contributions.

We would far rather hear from you the week before you resign than the week after. There is almost always a better-sequenced route — a grievance, a protected conversation, a without-prejudice approach, or a negotiated exit that produces more money with less risk than a contested claim realistically would.

If you have already resigned, do not assume the case is lost, but contact us quickly, because time runs from your last day.

The three-part test

1. A fundamental breach. The employer’s conduct went to the root of the contract.
2. Resignation in response. You left because of that breach, not for an unrelated reason.
3. No affirmation. You did not delay so long, or behave in such a way, as to accept it.

All three must be established. (Western Excavating (ECC) Ltd v Sharp.)

What counts as a fundamental breach

The breach may be of an express term — pay, hours, job title, location — or of an implied term, most often the implied term of mutual trust and confidence. Conduct found to breach that term includes:

• unwarranted and humiliating public criticism
• unjustified accusations of dishonesty or misconduct
• removing significant duties or status without cause
• failing to protect an employee from bullying
• refusing to investigate a serious grievance
• a disciplinary sanction wholly out of proportion
• persistent failure to pay agreed remuneration
• unilaterally imposing contractual change
• unreasonable changes to working pattern or place of work without agreement

(Malik v BCCI.)

The last straw. A breach can be one serious incident or a series of events culminating in a final act. Where you rely on a course of conduct, the final act need not itself be serious, but it must contribute something and must not be entirely innocuous. (Omilaju v Waltham Forest LBC.)

What is usually not enough. Ordinary unreasonable management. A decision you disagree with. A performance improvement plan properly applied. A change the contract expressly permits. A single brusque exchange. Tribunals distinguish between an employer being difficult and an employer repudiating the contract.

Affirmation: the trap that closes most claims

If your employer commits a fundamental breach and you carry on working normally without objection, you may be treated as having accepted it. The right to resign and claim is then gone.

There is no fixed period. What matters is whether your conduct signals acceptance. Continuing to work without protest, accepting a pay rise, applying for internal promotion, or simply saying nothing for months all point towards affirmation.

How to preserve your position. Put in writing that you do not accept the conduct, that you reserve your contractual rights, and that you are working under protest. Being signed off sick does not automatically amount to affirmation, but neither does it stop the clock.

Raise a grievance first, usually

A grievance gives the employer a chance to remedy the breach, which sometimes happens. It creates a contemporaneous record far more persuasive than an account constructed afterwards. And an unreasonable failure to use the grievance procedure can reduce your compensation by up to 25%.

It is also the natural moment for settlement discussions to open.

There are exceptions — where the breach is continuing and intolerable, where you are seriously unwell, or where the grievance would be heard by the person responsible. Take advice on sequencing.

Your resignation letter is evidence

It will be read out at a tribunal. It should:

• identify the specific conduct relied on, with dates
• refer to any earlier objection or grievance
• state that the conduct is a fundamental breach of contract
• state that you are resigning in response to it
• confirm whether you resign immediately or on notice

Where the breach is serious, you do not have to give notice. Resigning without notice is consistent with treating the contract as at an end, though working notice does not automatically destroy a claim if you make your position clear.

Do not send the first draft. Do not send it angry. Do not include anything you cannot prove. Saying you are leaving for “personal reasons” can be fatal.

Service and deadline

You usually need two years’ service, reducing to six months for terminations on or after 1 January 2027. No qualifying service is needed where the reason relates to pregnancy or maternity, health and safety, whistleblowing, Working Time rights, the National Minimum Wage, or discrimination.

Time runs from your last day. Three months minus one day, or six months minus one day where the limit starts on or after 1 October 2026.

TUPE

After a transfer, you may be able to resign and claim if working conditions would be substantially worse and this amounts to a material detriment — putting you at a serious disadvantage. Conditions include contractual terms, physical working conditions, and matters such as place of work.