Calculate your deadline
Enter the date of dismissal or the act you are complaining about, then your Acas dates if you have them. For most claims the limit is 6 months less 1 day if the act happened on or after 1 October 2026, and 3 months less 1 day if it happened before then. This is an estimate only.
How the rules work: how long do I have to make an employment tribunal claim?
Some claims have different rules. Continuing acts, the date of a resignation and other facts can change the deadline, so get urgent dates checked.
The usual rule
Since 1 October 2026, most claims must be brought within 6 months minus 1 day of the problem at work, under the Employment Rights Act 2025. If the problem happened before 1 October 2026, the old limit of 3 months minus 1 day usually still applies. GOV.UK explains that the period is put on hold while Acas helps resolve the dispute.
Dates you need
You need the dismissal date or act date, the date you notified Acas, the date the Acas certificate was issued and any continuing act arguments.
Urgent warning
If you are close to the deadline, do not wait for perfect advice. Get the date checked immediately and preserve your position.
Deadline calculation warning
The usual time limit sounds simple, but Acas early conciliation can alter the final date. Multiple incidents, continuing acts, dismissal dates and certificate dates can make the answer less obvious.
Information needed for a deadline review
You need the act or dismissal date, Acas notification date, Acas certificate date, whether the same respondent was named correctly and whether there are multiple claims with different dates.
What to do if close to time
If the deadline is close, prioritise preserving the claim. Do not spend days perfecting evidence while the filing window expires. Get the ET1 route checked urgently.