Employment tribunal time limits for unpaid wages : calculate what you are owed

• Dual regime: Until the cutover, most claims (including most pay claims) use 3 months minus 1 day. From 1 October 2026, most claims use 6 months minus 1 day, but only if your time limit starts on or after 1 October 2026.
• For pay and wages, Acas says the limit usually starts on the date you were not paid correctly (the relevant payday / deduction date).
• For a series of deductions, Employment Rights Act 1996 section 23 points to the last deduction or payment in the series for the presentation deadline.
• Grievance, disciplinary and appeal processes do not extend the limit. Early Conciliation can pause it if you notify Acas within the limit.
• "Not reasonably practicable" extensions exist in the Act but are exceptional. Do not plan on them.
• After Early Conciliation (if notified in time), you usually have at least one month from the certificate to present the claim.

Acas updated its employment tribunal time limits page on 4 September 2026. It states two layers at once:

1. Current default for most claims: 3 months minus 1 day.
2. From 1 October 2026: the time limit for most claims increases to 6 months minus 1 day, and this only applies if your time limit starts on or after 1 October 2026.

That second sentence is the whole game. The longer period is not a gift that rewrites every old claim on 1 October. What matters is the start date of your limitation clock, not the date you happen to fill in a form.

Regime A: clock starts before 1 October 2026

You stay on 3 months minus 1 day (for most claim types, including typical unpaid wages claims), even if Early Conciliation or the ET1 filing happens after 1 October 2026.

Example: Wrong payday on 20 August 2026. Clock starts 20 August 2026 (before 1 October). Limit: add three calendar months, take off one day → ends 19 November 2026 at 11:59pm on Acas's method. The October reform does not stretch this to six months because the clock started in August.

Regime B: clock starts on or after 1 October 2026

For most claims, you get 6 months minus 1 day.

Example: Wrong payday on 5 October 2026. Clock starts on/after the reform date. Limit: add six calendar months, take off one day → ends 4 April 2027 at 11:59pm using the same Acas arithmetic style.

Claims that already had six months

Acas already lists some claim types with 6 months minus 1 day even before the reform (for example statutory redundancy pay and equal pay). Unpaid wages / deduction claims are in the "most claims" bucket that moves from three to six months under the October 2026 change when the start-date rule is met. If your case mixes claim types, get advice: different heads can have different clocks.

Acas's own worked example: you were paid the wrong amount on 1 May. Add three calendar months, then take off one day. The time limit starts on 1 May and ends at 11:59pm on 31 July.

Mirror that method for any payday. Do not invent "90 days" or "the end of the third month" shortcuts that drift from Acas's calendar approach.

GBP unpaid wages example (Regime A): On 10 June 2026 your employer pays you £380 for a 35-hour week. At the April 2026 National Living Wage for age 21+ (£12.71), 35 hours should be at least £444.85. Shortfall that payday: £64.85. Clock for a claim about that payday starts 10 June 2026. Ordinary end date: 9 September 2026 (3 months minus 1 day). Notify Acas on or before that end date if you want the Early Conciliation pause.

Acas guidance on time limits:

• In most cases, the limit starts from the date the problem at work happened.
• For pay and wages, it starts from the date you were not paid correctly.

Employment Rights Act 1996 section 23 (unlawful deductions complaints) is more technical: the tribunal shall not consider the complaint unless it is presented before the end of the period of three months beginning with the date of payment of the wages from which the deduction was made (or the date a prohibited payment was received). Acas's public "3 months minus 1 day" framing is the practical expression of that three-month window that workers are told to use.

If several things went wrong (dismissal plus unpaid wages plus discrimination), clocks can differ by claim type. Map each head separately.

Many wage disputes are not one bad payday. They are a pattern.

Section 23(3) ERA 1996 says that where a complaint is brought in respect of a series of deductions or payments, the references to the deduction or payment are to the last deduction or payment in the series. Acas NMW guidance uses the same idea for tribunal timing: if there were several wrong underpayments in a row, you have 3 months minus 1 day from the most recent wrong deduction (subject to the October 2026 dual regime for which length applies).

Worked series example: Underpayments on paydays 28 February, 28 March, 28 April and 28 May 2026, each short by £50 (total £200). If they form a series, the presentation clock is tied to 28 May 2026, not February. Under Regime A: ordinary end 27 August 2026. Still notify Acas before that date. How far back the tribunal will look for earlier months is a separate question (Acas NMW pages discuss roughly up to two years of linked underpayments in guidance terms; that is not a free extension of the filing deadline).

A long quiet gap can break a series argument. Do not assume every historic shortfall automatically rides on the latest payday. If in doubt, protect the earliest risky date and get advice.

When you notify Acas within your employment tribunal time limit, Acas offers Early Conciliation and pauses your time limit until Early Conciliation ends. Notify late and you do not get that pause.

After Early Conciliation, if you notified in time, Acas says you will have at least one month from the date you received the certificate to make your claim. Sometimes you may have longer; working it out can be complicated. Only a tribunal finally decides whether a claim is in time. Acas conciliators cannot decide that point for you.

Acas states this without soft edges: going through grievance, disciplinary or appeal procedures does not change your time limit. If those procedures drag on, you still need to notify Acas before the limit runs out. Judges often expect you to have tried to resolve the dispute, but "waiting for HR" is not a limitation strategy.

Section 23(4) ERA 1996 lets a tribunal consider a late complaint if it is satisfied it was not reasonably practicable to present it in time, and then only within a further period the tribunal considers reasonable. Acas's public message matches the practical reality: you can still try to claim after the limit, but in most cases time limits are strictly enforced, and it is up to the judge.

Illness, misleading employer statements, or other rare facts sometimes feature in these arguments. "I was busy", "I hoped they would pay", or "the grievance was ongoing" are weak foundations. Treat the primary deadline as hard.

For many unlawful deduction complaints, section 23(4A) stops the tribunal considering deductions from wages paid more than two years before the date the complaint is presented (with limited carve-outs). That backstop is about how far back sums can go once you are in time to present. It does not replace the 3 months minus 1 day (or post-October 6 months minus 1 day) filing clock. Keep both ideas separate when you plan.

1. Identify the relevant payday (or last payday in a true series).
2. Decide which regime applies: did that clock start before 1 October 2026, or on/after?
3. Add 3 or 6 calendar months, then subtract 1 day, ending at 11:59pm on that date (Acas method).
4. Diary an earlier internal deadline to notify Acas (do not aim for 11:58pm on the last day).
5. Run Early Conciliation; note the certificate date; diary the post-certificate window (at least one month if you notified in time).
6. Present ET1 before your calculated last day.

Cross-cutover illustration: Last underpayment payday 15 September 2026 (Regime A: 3 months minus 1 day → 14 December 2026). Last underpayment payday 15 October 2026 (Regime B for most claims: 6 months minus 1 day → 14 April 2027). Same type of claim; different start dates; different lengths.

• Assuming 1 October 2026 lengthens every live dispute. Only clocks that start on/after that date get the new most-claims six-month rule.
• Counting "90 days". Use calendar months minus one day the way Acas illustrates.
• Waiting for grievance outcomes. The clock keeps moving.
• Treating a series as endless. The filing clock keys off the last deduction; older months still need a coherent series / linkage analysis for recovery.
• Relying on "not reasonably practicable". Exceptional, not a plan B you schedule in advance.
• Notifying Acas after the primary limit. No pause.

Time limits are unforgiving; your evidence should not be. Paye Mes Heures helps you date each underpaid period and total the pounds so you can see which payday starts the clock before you notify Acas. Pair that schedule with the Acas time limits page and, if the dates are tight, get advice the same week.

• https://www.acas.org.uk/employment-tribunal-time-limits
• https://www.gov.uk/employment-tribunals
• https://www.legislation.gov.uk/ukpga/1996/18/section/23
• https://www.acas.org.uk/early-conciliation/how-early-conciliation-works
• https://www.acas.org.uk/national-minimum-wage-entitlement/if-an-employer-does-not-pay-minimum-wage