How to Claim Unfair Dismissal at an Employment Tribunal

Under the Employment Rights Act 1996 (ERA 1996), every employee has the right not to be unfairly dismissed. A dismissal is unfair if the employer cannot show it was for one of the five potentially fair reasons: capability or qualifications, conduct, redundancy, statutory illegality, or some other substantial reason (SOSR).

Even where the employer identifies a fair reason, the dismissal can still be unfair if the employer did not follow a fair procedure. The tribunal will consider whether the employer acted reasonably in treating the reason as sufficient grounds for dismissal, having regard to the size and resources of the employer and principles of equity and the substantial merits of the case (s.98(4) ERA 1996).

It is worth noting that "dismissal" includes not only being sacked outright but also situations where a fixed-term contract expires and is not renewed, or where the employee is forced to resign because of the employer's conduct (constructive dismissal).

To bring an ordinary unfair dismissal claim, you must have at least two years' continuous employment with the same employer, calculated from the date your employment began to the effective date of termination (EDT). The EDT is usually the date your notice expires, or the date of summary dismissal if dismissed without notice.

Continuous service is calculated week by week. Breaks in employment generally break continuity, though some absences (such as sickness, maternity leave, or temporary cessation of work) may be counted. If you were dismissed during a probationary period or within the first two years, you normally cannot claim ordinary unfair dismissal — but you may still have a claim if the reason falls within the automatically unfair category.

If there is a dispute about your start date, the tribunal will examine the evidence including your contract, payslips, HMRC records, and any TUPE transfer documentation.

Certain reasons for dismissal are deemed automatically unfair, meaning no qualifying period of service is required. These include dismissal for making a protected disclosure (whistleblowing) under s.103A ERA 1996, asserting a statutory employment right (s.104 ERA 1996), reasons connected with pregnancy or maternity leave, trade union membership or activities, acting as an employee representative, or exercising the right to be accompanied at a disciplinary hearing.

The significance of an automatically unfair dismissal is twofold: the employee needs no minimum service and there is no cap on compensation for some categories (notably whistleblowing dismissals). The burden of proof shifts to the employer in some cases — for example, in redundancy-related trade union dismissals, the employer must show the reason was not the prohibited one.

If you believe your dismissal falls into one of these categories, it is crucial to identify and plead it correctly in your ET1, as the legal framework differs from ordinary unfair dismissal.

Where the employer claims the dismissal was for misconduct, tribunals apply the test established in British Home Stores Ltd v Burchell [1978]. The employer must demonstrate three things: a genuine belief in the employee's guilt, reasonable grounds for that belief, and a reasonable investigation carried out before forming that belief.

The tribunal does not decide whether the employee was actually guilty of the misconduct. Instead, it asks whether the employer's decision fell within the "band of reasonable responses" — that is, whether a reasonable employer could have decided to dismiss in those circumstances. This is an objective test, and the tribunal must not substitute its own view for that of the employer.

The quality of the investigation is often where employers fall down. A fair investigation typically requires the employer to gather evidence from witnesses, give the employee the opportunity to respond to the allegations, consider any mitigating circumstances, and follow its own disciplinary procedure. Failure to investigate adequately, or to follow the ACAS Code of Practice on Disciplinary and Grievance Procedures, will count against the employer.

The ACAS Code of Practice on Disciplinary and Grievance Procedures sets out the minimum standard of fairness that employers should follow when dealing with disciplinary matters. While the Code is not legally binding, tribunals are required to take it into account, and an unreasonable failure to follow it can result in compensation being increased by up to 25%.

The Code requires employers to carry out a reasonable investigation, inform the employee in writing of the allegations, hold a disciplinary meeting at which the employee can put their case, allow the employee to be accompanied by a colleague or trade union representative, and provide a right of appeal. The entire process should be conducted without unreasonable delay.

If your employer failed to follow these basic steps — for example, dismissing you without a hearing, not allowing you to appeal, or not disclosing the evidence against you — this significantly strengthens your unfair dismissal claim. Conversely, if you unreasonably failed to follow a grievance procedure before resigning, your compensation could be reduced by up to 25%.

The ET1 is the claim form used to bring proceedings before the employment tribunal. You can file online at www.gov.uk/employment-tribunals. The form asks for details of your employment (start date, end date, job title, earnings), the respondent's (employer's) name and address, and the details of your complaint.

The strict time limit is 3 months minus 1 day from the effective date of termination. However, the ACAS early conciliation period effectively pauses this clock: the time between notifying ACAS and receiving your certificate does not count towards the deadline. If your time limit falls on a day the tribunal is closed (weekend or bank holiday), it extends to the next working day.

Be thorough in the "details of claim" section. Set out the facts in chronological order, identify the legal basis for your claim, and specify what remedy you are seeking. You do not need to cite case law, but you should clearly state whether you are claiming ordinary unfair dismissal, automatically unfair dismissal, or both. Attach relevant documents if filing online, or list them if posting the form.

If your unfair dismissal claim succeeds, the tribunal may award two types of compensation. The basic award is calculated using a statutory formula based on your age, length of service (capped at 20 years), and weekly pay (capped at a statutory maximum, reviewed annually). It works like a redundancy payment: half a week's pay for each year of service under age 22, one week's pay for each year aged 22–40, and one and a half weeks' pay for each year aged 41 or over.

The compensatory award is intended to compensate you for the financial loss caused by the dismissal. It covers loss of earnings (past and future), loss of statutory rights, loss of pension rights, and expenses incurred in seeking new employment. The compensatory award is subject to a statutory cap (the lower of 52 weeks' pay or the statutory maximum, reviewed annually), except in cases of whistleblowing or health and safety dismissals where the cap does not apply.

The tribunal will also consider whether you have taken reasonable steps to mitigate your loss — for example, by actively looking for new work. If you have found a new job at a lower salary, the compensatory award covers the difference. If you have not made reasonable efforts to find work, the award may be reduced.

A Polkey reduction (named after the case of Polkey v AE Dayton Services Ltd [1987]) allows the tribunal to reduce your compensatory award to reflect the chance that you would have been dismissed anyway, even if a fair procedure had been followed. For example, if your employer dismissed you for redundancy without proper consultation, but the tribunal concludes there was a 70% chance you would have been made redundant anyway, your compensatory award would be reduced by 70%.

Polkey reductions are common in cases where the employer had a fair reason to dismiss but followed an unfair procedure. The tribunal will assess the percentage likelihood of dismissal had a fair process been followed, and reduce the award accordingly. This can result in significant reductions — in some cases to nil if dismissal was inevitable.

Additionally, the tribunal may make a separate reduction for contributory fault under s.123(6) ERA 1996, if the employee's own conduct contributed to the dismissal. Polkey and contributory fault reductions are applied independently and can be combined, substantially reducing the overall award.