- where authorised by statute or the courts;
- where agreed and part of the contract of employment;
- where there's been an earlier overpayment; or
- with your advance written agreement.
The employer is entitled to deduct wages that have been overpaid to you – even if the overpayment is as a result of the employer’s own mistake. Even so, it is sometimes possible to negotiate that sums should not be repaid, or at least that repayments should be made in stages, where you have reasonably failed to spot the overpayment and you have spent or relied on the money, not realising that you were not entitled to it.
Many employers impose an express contractual duty on their staff to check their pay and to report discrepancies. There is no implied contractual duty to check your pay and report discrepancies in the absence of a clear written term – but checking your pay and quickly querying any apparent underpayment or overpayment is obviously very sensible!