Report minimum-wage underpayment to HMRC

1. Confirm an underpayment. Run the am-I-being-underpaid diagnostic to compute effective hourly rate after deductions vs the applicable band floor.
2. Gather evidence. Payslips, written hours records (or your own logs), contract or worker agreement, evidence of any deductions (uniform, accommodation, training).
3. File via gov.uk. Submit at gov.uk/pay-and-work-rights. The route is anonymous; HMRC/FWA will not name you to the employer.
4. Engage with the investigator. Respond to any follow-up; an officer may need clarifying detail. The employer will not be told you complained.
5. Receive the notice of underpayment. If upheld, the employer must repay arrears at the CURRENT rate (not historic) plus a 200% penalty to HMRC up to £20,000 per worker.

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Arrears at the current NMW rate (not the historic rate at the time of the underpayment). Up to six years of back pay. Plus a 200% penalty payable to HMRC, capped at £20,000 per worker. In the worst cases the employer can be prosecuted criminally and directors disqualified^gov.uk.

• Issue back pay direct to the worker before the employer pays. The arrears flow employer to worker.
• Award interest on the arrears. Interest is an Employment Tribunal route.
• Pursue unfair dismissal or constructive dismissal. That is a tribunal route.