Guide · Time limits

Your effective date of termination

The unfair dismissal time limit runs from the "effective date of termination" — the EDT. It sounds like it should just be the date on the dismissal letter. Often it is. Sometimes it isn't, and the difference can decide whether a claim is in time at all.

The basic rules

The EDT is defined in section 97 of the Employment Rights Act 1996. In outline:

• Dismissal with notice — the EDT is the date the notice expires, not the date it was given. Told on 1 March that you're dismissed with one month's notice? The EDT is when that notice period ends.
• Dismissal without notice (summary dismissal) — the EDT is the date the dismissal takes effect: broadly, when it is communicated to you.
• Fixed-term contract ending — the EDT is the date the term expires.
• Constructive dismissal — where an employee resigns in response to the employer's conduct, the EDT is generally when the resignation takes effect: immediately if no notice is given, or when any notice worked ends.

Where it gets less obvious

Payment in lieu of notice (PILON). Being dismissed immediately with a payment covering your notice period is not the same, for EDT purposes, as working out notice. Where dismissal takes effect straight away and notice is paid rather than worked, the EDT is usually the immediate dismissal date — which makes the deadline earlier than people assume. This is one of the most common ways claims end up out of time.

When were you actually told? A dismissal generally takes effect when it is communicated. Case law has established that where dismissal is by letter, time doesn't start running until the employee has read it or has had a reasonable opportunity to read it — the leading case involved a letter that arrived while the employee was away. If there's any gap between the letter's date, its arrival, and your reading of it, the precise EDT can genuinely be in dispute.

Disputed or messy endings. Ambiguous words at a heated meeting, an appeal that's ongoing, being told to "stay home while we sort this out" — endings are not always clean, and where the ending is unclear, so is the EDT. Note that pursuing an internal appeal does not normally pause the tribunal clock: an unsuccessful appeal usually leaves the original EDT standing.

Once you've identified the date (or the earliest arguable one), the calculator applies the statutory arithmetic and shows each step:

Compute your dates →

One more wrinkle worth knowing exists

For a few specific purposes — mainly whether you have enough qualifying service to claim at all — the law can treat the EDT as extended by the statutory minimum notice you were entitled to. It's a narrow rule with specific conditions, but if your service is just short of a qualifying threshold, it's a question worth putting to an adviser rather than assuming you don't qualify.

If the dates are in dispute

Whether a particular date is legally your EDT is exactly the kind of individual question this site doesn't answer — it depends on your contract, your correspondence, and what was said and when. ACAS (0300 123 1100), your union, Citizens Advice, a law centre, or a regulated adviser can look at the actual documents. Take the documents with you: the letter, the meeting notes, the dates things arrived.