You have 3 months to act. Not a day more.

The Employment Tribunal 3-month deadline is one of the strictest in law. Miss it and your claim is almost certainly gone — regardless of how strong it is. Check your dates now.

What is the time limit for an Employment Tribunal claim?

For most claims — unfair dismissal, constructive dismissal, wrongful dismissal — you have 3 months minus one day from the effective date of termination (or the date of the act you are complaining about). For discrimination claims the same 3-month rule applies. For redundancy pay claims it is 6 months. ACAS early conciliation must be started before this deadline, and contacting ACAS freezes the clock.

What is the effective date of termination?

For dismissals with notice, it is the date your notice period ends — even if you were paid in lieu and did not work the notice. For summary dismissal (fired on the spot), it is the date you were told you were dismissed. For constructive dismissal, it is the date your resignation took effect. Always count from the last day you were actually employed.

Can the 3-month deadline be extended?

Rarely. The tribunal can extend the deadline if it was not reasonably practicable to bring the claim in time — but this is a high bar. ACAS early conciliation automatically extends the period. Internal grievance processes or appeals do NOT pause the clock.

Does an internal appeal pause the 3-month clock?

No. This is one of the most common mistakes. Going through an internal appeal or grievance process does NOT stop the employment tribunal deadline. You must contact ACAS within 3 months regardless of whether your internal processes are still ongoing. You can run both simultaneously.

What happens if I miss the deadline?

Your claim will almost certainly be rejected. The tribunal has very limited discretion to allow late claims. Once the deadline passes and ACAS has not been notified, you are effectively time-barred — regardless of how strong your case is.

How does ACAS early conciliation affect my deadline?

Contacting ACAS freezes the 3-month clock from the day you notify them. When ACAS issues your certificate, you get additional time to file your ET1 — the number of days ACAS had the case, plus one month. Start My Claim calculates your exact deadlines automatically.

Can I claim for multiple events — which date do I use?

If you have a series of discriminatory acts or a continuing course of conduct, the clock runs from the last act in the series. For separate, discrete acts, each has its own 3-month clock. For unfair dismissal, there is only one relevant date: your effective date of termination.

Tribunal deadline calculator

Enter your dates below to see your exact filing deadlines.

With ACAS — adjusted ET1 deadline

This calculator provides an estimate only. Start My Claim tracks your deadlines automatically when you sign up.

Start My Claim — Employment Tribunal Deadline Calculator

Free employment tribunal deadline calculator. Enter your dismissal date to see your exact 3-month filing deadline, adjusted for ACAS early conciliation.

Check your deadline now

Free · No signup required · Includes ACAS adjustment

The time limit rules, clearly explained

The mistakes that kill claims

How ACAS early conciliation extends your deadline

Contacting ACAS freezes the 3-month clock. This is the only legitimate way to get more time.

Calculate your original 3-month deadline (dismissal date + 3 months minus 1 day)
Count the days ACAS had your case (Day A = date you contacted ACAS; Day B = date of ACAS certificate)
Add (Day B minus Day A) days to your original deadline
Add one further month
The later of the original deadline and this new date is your ET1 filing deadline

Use the calculator above to get your exact dates.

Time limit — common questions

Stop watching the calendar manually.

Start My Claim tracks your 3-month deadline automatically, notifies you before it passes, and builds your entire claim — ET1, chronology, witness statement — in plain language.

Check what your case is worth — free

Free to start · Deadlines tracked automatically · Email reminders before key dates

Your claim, estimated

What could you actually be owed?

No sign-up, no card, no email. Your numbers just appear below as you type — then you decide whether to build the full case.

Start My Claim is not a law firm. This calculator provides estimates only and does not constitute legal advice.

Employment Rights Act 1996