YourWorkRights

Unfair & constructive dismissal: a guide to your rights

What makes a dismissal unfair, the exceptions to the two-year rule, and how constructive dismissal claims actually work.

1. What is unfair dismissal?

Unfair dismissal is when your employer terminates your contract of employment without a fair reason or without following a fair procedure. To be protected from unfair dismissal, you usually need to have been continuously employed for at least two years.

The two-year rule and its exceptions

While the two-year service requirement applies to most claims, there are important exceptions where a dismissal is "automatically unfair," regardless of how long you have been employed. These include being dismissed for:

  • Discrimination related to a protected characteristic (age, disability, gender reassignment, marriage/civil partnership, pregnancy/maternity, race, religion/belief, sex, sexual orientation).
  • Whistleblowing — making a protected disclosure in the public interest.
  • Asserting a statutory right — for example, asking for the minimum wage, working time rights, or written terms.
  • Pregnancy or family leave — any reason connected to pregnancy, maternity, paternity, adoption or shared parental leave.
  • Health and safety activities — raising a genuine H&S concern or refusing dangerous work.
  • Trade union membership or activities.
No qualifying service needed for these

If any of these apply, the two-year rule does not protect your employer — you can claim from day one of employment. The three-month-minus-one-day time limit still applies, so act quickly.

2. The five potentially fair reasons

Under the Employment Rights Act 1996, an employer can only dismiss fairly for one of five reasons — and must still follow a fair process:

Reason 1

Capability or qualifications

You cannot do the job — through performance, ill health, or lack of qualifications. Fairness requires warnings, support, and a chance to improve (or, for ill health, medical evidence and consideration of adjustments).

Reason 2

Conduct

Misconduct, from persistent lateness to gross misconduct. Even gross misconduct requires a fair investigation and disciplinary hearing — an employer who skips the process risks an unfair dismissal finding even if the allegation is true.

Reason 3

Redundancy

The role must genuinely disappear, with fair selection and consultation. See our Redundancy Pathway guide for what a fair process looks like.

Reason 4

Statutory restriction

You legally cannot do the job — for example, a driver who loses their licence. Rare, and the employer must still consider alternatives.

Reason 5

Some other substantial reason (SOSR)

A catch-all for genuine, substantial reasons that do not fit the other four — such as an irretrievable breakdown in working relationships or a business reorganisation. Employers must prove the reason was substantial and the process fair.

3. Fair reason is not enough — the procedure matters

Even with a fair reason, a dismissal is unfair if the process was unfair. Tribunals look at the ACAS Code of Practice: was there a proper investigation, written allegations, a hearing with the right to be accompanied, a chance to respond, and a right of appeal? An unreasonable failure to follow the ACAS Code can increase compensation by up to 25%.

4. Constructive dismissal

Constructive dismissal is when you resign because your employer's conduct has made your position untenable. Legally, you must show:

  • A fundamental breach of contract by your employer — such as bullying, unilateral pay cuts, or a total breakdown of trust and confidence caused by their behaviour.
  • You resigned because of that breach — not for another reason.
  • You did not wait too long — delaying your resignation can be treated as accepting ("affirming") the breach.
Constructive dismissal is high-risk

You are giving up your job and your income before any tribunal has ruled. These claims are harder to win than ordinary unfair dismissal because the burden is on you to prove the breach. Exhaust the grievance route first and get advice before you resign.

The safest sequence is usually: raise a written grievance, give your employer a genuine chance to fix the breach, and resign only if they fail — stating clearly in your resignation letter that you are treating their conduct as a fundamental breach of contract.

5. What to do next