Constructive dismissal

Constructive dismissal is when you resign because your employer has seriously breached your contract, so you feel you have no real choice but to go. The law treats it as a dismissal, which means you can claim unfair dismissal at a tribunal. Success is hard. The breach has to be serious, you usually need two years’ service, and both gov.uk and Acas advise raising the problem with your employer before you leave.

What counts

gov.uk says the conduct must be serious, and gives these examples:

• not paying you, or demoting you without good reason
• forcing unreasonable changes to how you work
• allowing other employees to harass or bully you

Acas adds regularly underpaying without good reason, discrimination, ignoring a grievance, and making unagreed changes to hours or place of work. Either a single serious incident or a series of events taken together can be enough.

Disliking your job, being under pressure or having a difficult relationship with a manager does not meet that bar unless it amounts to a serious breach. If a restructure forces changes on you, the redundancy rights guide may fit better.

What to do before you resign

Both gov.uk and Acas say to try to resolve the problem with your employer first. Acas sets out the order: raise it informally, then raise a formal grievance if that fails, and get legal advice before you resign. Our grievance guide walks through the process.

Keep notes with dates, copies of letters and emails, and any payslips that show underpayment. If you are in a union, tell your rep before you take any step you cannot undo.

Timing, and the risk of staying too long

gov.uk warns that if you have a case, you should leave immediately, because your employer may argue that staying meant you accepted the treatment. That sits beside the advice to try to resolve things first, and the two can pull in different directions. Speak to Acas, your union or a solicitor before you decide, so someone can look at your facts and tell you how long is too long.

Resigning

Acas says you should explain your reasons clearly in your resignation letter. After a serious breach you may be able to leave without working your notice, but this could breach your contract, so legal advice comes first. The guide to resigning properly covers the letter itself.

The service you need

Acas says you usually need employee status and two years’ service. Less than two years may be enough where the resignation relates to pregnancy, childbirth or maternity leave, health and safety, whistleblowing, Working Time rights or National Minimum Wage rights.

The two-year rule is due to change. The government’s timeline, updated on 22 October 2026, lists a cut in the unfair dismissal qualifying period to six months among the measures that take effect on 1 January 2027. That date has not yet arrived, and the government says future dates may change, so check gov.uk if your resignation falls near it. Our Employment Rights Act 2025 guide tracks the timeline.

Time limits and conciliation

gov.uk says you usually have to make a tribunal claim within six months of the problem happening, and within three months if the problem was before 1 October 2026. You will usually need an early conciliation certificate from Acas before you can start a claim. The date from which the clock runs matters in these cases, so confirm yours with Acas straight away. See tribunal time limits and early conciliation.

Other claims that need no service

Where the problem is discrimination, whistleblowing or another automatically unfair reason, Acas says there is no two-year requirement for the dismissal claim. A constructive dismissal can sometimes be argued alongside one of these. Our guides on discrimination and whistleblowing explain those routes, and an adviser can say which claim fits your facts.

Settlement and what follows

If you sign a settlement agreement, Acas says you cannot bring a constructive dismissal claim to a tribunal. Read the list of claims first, and see our settlement agreements guide.

Take advice on your facts before you decide.