Employees who believe they have been unfairly dismissed or unfairly treated currently have three months to bring an employment tribunal claim. That limitation period will increase to six months from October 2026. This is against the backdrop of an increased mandatory early conciliation period to try to resolve claims before they go to tribunal and a tribunal backlog that shows no signs of abating.

In this article we explore the impact this extension will have on employers, and what actions they should be taking to mitigate the consequences.

What is the three-month limitation period?

For most types of employment claim, there is a three-month limitation period. Technically, this limitation period is three months minus one day from the date of dismissal or the date on which the act occurred that created the claim (such as discrimination or harassment). In the case of unlawful deduction from wages claims, where an employee is claiming arrears of holiday pay for example, the time limit starts from the date of the last of the series of deductions.

If an employee fails to bring their claim within the three-month time limit, it will be timed out unless they can provide a very good reason why they should be allowed to bring the claim. This is a critical point in litigation, where employers can get claims dismissed for being out of time, saving money and administrative burden. When defending an employment tribunal claim, the first action should always be to check the time limits.

Acas conciliation period extended from six weeks to 12 weeks

Before an employee can make the claim, they must go through a mandatory early conciliation process, during which Acas (the independent advisory, conciliation and arbitration service) will try to help the parties resolve the claim without going to tribunal. During this time, the clock on the three-month time limit is paused, prolonging the time for a claim to be brought. If it can’t be resolved, the claim proceeds to an employment tribunal. In December 2025, this period of conciliation was extended from six weeks to 12 weeks.

Tribunal backlog only making matters worse

The employment tribunal system currently has a significant backlog, with claims taking as long as five years to be heard. There are growing calls for a major system overhaul to clear cases and provide swifter access to justice for both parties. Employers and employees are already suffering the consequences of tribunal claims not being heard within a reasonable period of time.

The extension of the limitation period to six months will only exacerbate the issue for employers. With the 12-week Acas conciliation period, the six-month limitation period and current tribunal delays stacked together, employers will wait at least three years for a hearing – and possibly more than five years, according to recent reports.

How should employers prepare for longer tribunal claim deadlines?

The extension to a six-month limitation period increases the risk of a claim being brought out of the woodwork, meaning employers are exposed for longer. Employees have more time to take legal advice, gather documents, seek disclosure through data subject access requests and reflect on whether to litigate. When you factor in the extended Acas conciliation period, a claim can still be brought nine months after the dismissal.

Evidence retention and witness statements

That uncertainty means employers will need to retain sufficient documents to support dismissal decisions and may even need to take statements from witnesses to secure an accurate record of the key details. This will be particularly important in cases involving discrimination, whistleblowing or performance management where the tribunal will scrutinise not just the final decision, but the process leading up to it. For higher-risk decisions, employers should retain a ‘decision file’ containing key documents such as meeting notes, rationale, correspondence, policies, legal/ HR input and contemporaneous witness statements.

Employers also need to ensure that witnesses key to the successful defence of a claim can be contacted and called upon if they have left their employment. To that end, employers should review post-termination obligations in their template contracts and settlement agreements, and consider including a requirement that employees provide reasonable assistance in future employment tribunal claims or related proceedings. This might mean providing information, helping to locate documents or attending as a witness, for example. This is particularly relevant for senior employees, HR personnel, managers and others involved in dismissal, grievance, redundancy or disciplinary decisions. Employers should consider whether their contractual documents give them sufficient protection where key witnesses have left the business by the time a claim is issued.

Review data retention processes

Employers should also review their document retention policies and auto-deletion settings to ensure emails, Teams chats and HR system notes are retained long enough to cover potential claim periods.

Manager training is essential

Managers should understand that informal comments, rushed notes and inconsistent explanations may still be examined many months later. They should be encouraged to record the rationale for decisions at the time, particularly in relation to performance, conduct, redundancy selection, flexible working, sickness absence and adjustments, taking guidance from HR.

Not only are these steps good practice, but they will provide a strong foundation for successfully defending claims or negotiating low-value settlements – however long it takes.

If you would like to discuss how these changes could affect your organisation, please contact Charlie Barnes or your usual RSM contact.

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