UK Unpaid Wages & Unlawful Deductions Calculator (2026)
Work out how much unpaid pay and how many unlawful deductions you are owed, reconcile each pay period, and build a claim summary with the current employment-tribunal time limit.
How It Works & Methodology
This tool helps you total what an employer owes you: unpaid wages checked pay period by pay period, and deductions from pay classified as lawful or unlawful under the Employment Rights Act 1996. It then produces a claim summary with the amount owed, the tribunal time limit for the most recent deduction and the next steps (ACAS early conciliation and the Fair Work Agency).
Key Assumptions & Scope:
- Figures are gross (before tax and National Insurance) wages actually payable to the worker; the tool does not calculate tax, National Insurance or pension deductions.
- The six-month employment-tribunal time limit applies where the deduction, or the last deduction in a series, falls on or after 1 October 2026 (Employment Rights Act 2025). Earlier deductions keep the three-months-minus-one-day limit.
- A two-year backstop generally limits how far back you can claim (ERA 1996 s.23(4A)), except for certain statutory payments such as statutory sick pay, maternity pay and tips.
- For retail till shortages and stock deficiencies, an employer may only deduct up to 10% of gross pay on that pay day, must put it in writing and must reclaim it within 12 months.
- This is an estimate to help you understand what you may be owed, not legal advice. Check your contract and get advice from ACAS or a trade union before acting.
Frequently Asked Questions
When is a deduction from my wages unlawful?
An employer can only make a deduction if it is required by law (for example tax), allowed by a written term in your contract, or something you agreed to in writing beforehand. Any other deduction, or a shortfall in the wages you were due, is treated as an unauthorised deduction you can claim back.
How long do I have to claim unpaid wages?
For deductions, or the last deduction in a series, on or after 1 October 2026 you have six months to present an employment-tribunal claim; earlier deductions keep the three-months-minus-one-day limit. You must notify ACAS (early conciliation) before making a claim, and a two-year backstop generally applies.
What is the 10% rule for retail workers?
If you work in retail, an employer may deduct for till shortages or stock deficiencies only if your contract allows it, and the deduction cannot exceed 10% of your gross pay on that pay day. The employer must tell you in writing and reclaim the money within 12 months.