Employment Tribunal Time Limit

The three-months-less-one-day rule that governs nearly every employment tribunal claim — how it is calculated, when ACAS pauses it, and what happens when it expires.

What is the time limit for an unfair dismissal claim?

Three months less one day from the effective date of termination. The effective date of termination is generally the last day you worked, or the date the notice period ends if you were given notice. If your last day was 15 March, your base deadline is 14 June — but that deadline is paused while ACAS Early Conciliation runs, so your actual filing date will be later.

What is the time limit for a discrimination claim?

Three months less one day from the discriminatory act, or from the last act in a series of connected acts. Discrimination cases often involve conduct that builds up over time, and tribunals can treat a course of related conduct as a continuing act — so the clock runs from the final incident in the series, not the earliest. The extension test for discrimination is the more flexible just-and-equitable standard rather than the stricter not-reasonably-practicable test that applies to unfair dismissal.

How does ACAS Early Conciliation affect the time limit?

The clock pauses automatically from Day A, the day ACAS receives your notification, until Day B, the day the EC certificate is issued. Your new deadline is the original deadline plus the number of days from Day A to Day B. If the extended deadline would leave you fewer than one month from Day B, you are automatically given one month from Day B instead. Notifying ACAS never shortens the window you have to file.

What happens if I miss the employment tribunal time limit?

The tribunal will normally reject a late claim. It has a limited discretion to extend time under a statutory test. For unfair dismissal the test is whether it was not reasonably practicable to present the claim in time, which is strict and rarely satisfied. For discrimination and most other claims the test is whether it is just and equitable to extend time, which gives the tribunal broader flexibility and is more commonly granted. A late claim is not automatically hopeless, but the odds are significantly worse, and you must explain why you are late.

What is the effective date of termination and why does it matter?

The effective date of termination (EDT) is the statutory concept that fixes when employment ends for the purpose of calculating the unfair dismissal time limit. It is the date the notice period expires if notice is given, the date of summary dismissal if none is given, and the date a fixed-term contract expires if it ends without renewal. Getting the EDT wrong — even by a day — can make a claim out of time. Where an employer pays in lieu of notice rather than allowing the notice period to run, the EDT is the last day worked, not the date the payment covers.

Does the time limit apply to equal pay claims?

Equal pay claims under the Equality Act 2010 have a different time limit. You generally have six months from the end of the employment to bring the claim, rather than three months. The six-month period applies even if the employment ended voluntarily. ACAS Early Conciliation is still required before an equal pay claim in most cases, and the stop-the-clock rule applies in the same way.

Employment Tribunal Time Limit

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Glossary · Employment Tribunal

Employment Tribunal Time Limit

Last reviewed: June 2026

Employment Tribunal track

For most employment tribunal claims the deadline is

three months less one day

from the relevant act — typically the effective date of termination for unfair dismissal or the date of the discriminatory act — and that deadline is

automatically extended by the duration of ACAS Early Conciliation

while conciliation runs.

Where this comes from

Employment Rights Act 1996, s.111

— the primary time limit for unfair dismissal; three months from the effective date of termination. Extension only where it was not reasonably practicable to present in time.

Equality Act 2010, s.123

— time limit for discrimination claims; three months from the act or the last act in a series. Extension where just and equitable.

Employment Tribunals Act 1996, s.18B

— the stop-the-clock mechanism; the time limit is extended by the number of days from Day A to Day B of ACAS Early Conciliation.

Dedman v British Building and Engineering Appliances Ltd [1974] ICR 53

— the Court of Appeal established that the not-reasonably-practicable extension is narrowly interpreted; ignorance of the time limit alone does not satisfy it.

Robertson v Bexley Community Centre [2003] EWCA Civ 576

— the Court of Appeal on the just-and-equitable discretion: there is no presumption in favour of extension, and promptness after discovering the right to claim is important.

The time limit in plain English

Every employment tribunal claim has a deadline. Miss it, and the tribunal will ordinarily refuse to hear the case — not because your underlying complaint lacks merit, but because Parliament has decided that disputes should be brought promptly. The standard deadline for most claims is

from the act or omission being complained of.

Take unfair dismissal. Under section 111 of the Employment Rights Act 1996, you must present your claim within three months of the

effective date of termination

(EDT). The EDT is the day your employment actually ends — the last day of your notice period if you were given notice, or the day you were told to leave immediately if you were dismissed without it. Three months less one day from, say, 15 March is 14 June, not 15 June. Computing the date wrongly by a single day can — and does — make claims out of time.

For discrimination claims under section 123 of the Equality Act 2010 the start point is the discriminatory act rather than a termination date. Where discrimination happens as part of a continuing course of conduct — a series of related acts that form one connected policy or practice — the clock runs from the last act in that series. A single hostile comment, standing alone, starts the clock on the day it happens. But a pattern of exclusion or harassment that culminates months later may allow you to treat the whole course of conduct as one act and use the final incident as the start point. Whether acts are sufficiently connected is a question of fact for the tribunal; do not assume everything can be joined.

The EDT for unfair dismissal purposes is a statutory concept with some specific rules. Where an employer pays wages in lieu of notice (PILON) rather than allowing the notice period to run, the EDT is the last day worked — not the date the PILON payment covers. So if you are dismissed without notice on 1 March and paid six weeks in lieu, your EDT is 1 March, not the date six weeks later. This is a common source of error, because the employee naturally assumes the payment extends the employment.

The interaction with

ACAS Early Conciliation

is described in section 18B of the Employment Tribunals Act 1996 and works like this. When you notify ACAS, the clock pauses. The pause begins on Day A (the day ACAS receives your notification) and ends on Day B (the day ACAS issues your Early Conciliation certificate). Your new deadline is your original deadline plus the number of days from Day A to Day B. There is also a floor: if the resulting date would leave you fewer than one month from Day B to file, you get a full month from Day B instead. The effect is that Early Conciliation can only lengthen the window, never shorten it.

What happens if the deadline is missed? For unfair dismissal the tribunal can only extend time where it was

not reasonably practicable

to present the claim in time and it was presented within a further reasonable period. This is a strict test. The courts have consistently held that not knowing about the time limit is not enough — you are expected to take steps to find out. Postal delays, administrative errors and personal difficulties have all been refused. It is, genuinely, only in unusual circumstances that the extension is granted for unfair dismissal.

For discrimination and most other claims, the tribunal has a broader discretion: it can extend time if it considers it

to do so. This is a lower hurdle — there is no exhaustive list of factors — but the Court of Appeal in

Robertson v Bexley Community Centre

confirmed that there is no presumption in favour of granting an extension. Tribunals weigh the length of the delay, the reason for it, the merits of the underlying claim, and any prejudice to either side. Acting promptly once you know or should know about your rights significantly improves the chances of an extension being granted.

How the calculation works in practice

Worked example — PILON and ACAS extension

Amara is dismissed summarily on

. She is told her employment ends immediately and is paid eight weeks in lieu of notice. Her contract entitled her to eight weeks notice.

Because the employer paid PILON rather than allowing notice to run, the

EDT is 3 February 2026

— the day employment actually ended — not the date eight weeks later. Her base unfair dismissal deadline is

(three months less one day from 3 February).

Amara notifies ACAS. That is Day A. The employer declines to engage in conciliation; ACAS issues the EC certificate on

Effective date of termination

Base deadline (3 months less 1 day)

Day A (ACAS notification)

Day B (EC certificate issued)

Days paused (Day A to Day B inclusive)

to submit her ET1. Had she mistakenly calculated her EDT as eight weeks after dismissal (around 30 March), she would have thought her base deadline was 29 June and might not have hurried. The PILON rule makes the real deadline much earlier, and missing it would be fatal to an unfair dismissal claim.

Now suppose the employer had engaged in the full six weeks of ACAS conciliation without settling. Day B would then be around

, giving a pause of 42 days. The new deadline would be

. The floor rule would not be triggered here because 13 June is more than one month after Day B.

Common pitfalls for claimants

• Miscalculating the EDT when PILON is paid.
• The EDT is the day employment ends, not the day the payment-in-lieu covers. If you were dismissed immediately and paid two months in lieu, your clock started the day you were dismissed — not two months later. This is the single most common time limit error.
• Assuming all claims share the same deadline.
• Unfair dismissal uses the EDT. Discrimination uses the date of the act. Unlawful deduction from wages uses three months from the deduction. Equal pay uses six months from the end of employment. If you have multiple claims, each may have its own calculation.
• Waiting to notify ACAS until the last moment.
• You are allowed to notify ACAS even when you are not certain you want to proceed. The pause is automatic and costs nothing. Notifying early gives you the full conciliation period as a buffer rather than a window that is already nearly closed.
• Treating ignorance of the law as an excuse.
• For unfair dismissal, not knowing about the three-month time limit is not ordinarily enough to satisfy the not-reasonably-practicable test. Tribunals expect claimants to take steps to find out. The test is strict; plan on the basis that you will not be given a second chance.
• Not counting days correctly.
• Three months less one day from 15 March is 14 June, not 15 June and not 15 June minus one day. Work from the same date in the month three months forward, then subtract one day. If in doubt, calculate to the earlier date.
• Assuming a discrimination series continues indefinitely.
• Conduct must be sufficiently connected to be treated as a continuing act. A long gap between incidents, or a change in the nature of the treatment, may mean the earlier incidents are time-barred even if a later one is not. You need to identify, clearly, which acts form the series and when the last one occurred.

Frequently asked questions

Sources & further reading

• Employment Rights Act 1996, s.111
• — the unfair dismissal time limit and the not-reasonably-practicable extension.
• Equality Act 2010, s.123
• — the discrimination time limit and the just-and-equitable discretion.
• Employment Tribunals Act 1996, s.18B
• — the ACAS Early Conciliation extension mechanism.
• Employment Rights Act 1996, s.97
• — the statutory definition of effective date of termination.
• ACAS — Early Conciliation
• — how the ACAS process works and how to notify.
• gov.uk — Employment tribunal time limits
• — official guidance on deadlines for different claim types.

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Last reviewed: June 2026.

Statutory provisions and case law are checked against current legislation. Start My Claim is self-service software, not a law firm or claims management company. Nothing on this page is legal advice.