Employment tribunal deadline calculator

Updated August 2026

From 1 October 2026 the standard time limit to bring most tribunal claims doubles from three months to six, but only for things that happen on or after that date. This calculator applies the correct regime automatically and factors in Acas early conciliation, which most other calculators skip.

Why this needs a calculator most tools skip

The regulation that makes this change (the Employment Tribunal (Extension of Time Limits) Regulations 2026) has a transitional provision most calculators don't implement: the extended six-month limit only applies where the act complained of happened on or after 1 October 2026. If your dismissal was in September 2026, you're still on the old three-month clock even if you're filling this in during November. Both regimes run side by side for months, which is exactly the situation this tool is built to handle correctly.

What early conciliation actually does to the date

Contacting Acas for early conciliation pauses your limitation clock while it runs, and you're guaranteed at least one month after your certificate date to lodge a claim, even if almost no time was left when you started. Since 1 December 2025 the maximum conciliation window is 12 weeks, up from six, which can meaningfully extend your working deadline if conciliation runs long. Combined with the six-month base period, some claimants now have over nine months in total before a claim must be filed.

What this tool doesn't cover

Scotland and Northern Ireland have separate tribunal provisions not modelled here. Some claim types (certain discrimination continuing-act situations, for instance) have their own timing rules that a general calculator can't fully capture. And this only estimates a working deadline; it isn't a substitute for checking with Acas directly or a solicitor, especially if your date is close. For the wider context on what changed and why, read our explainer on the Employment Rights Act changes.