Retail giants WH Smith, Marks & Spencer and Argos are among firms that have been criticised for breaking minimum wage rules.
Almost £5m was found to be owed to around 63,000 workers following investigations by Her Majesty's Revenue and Customs (HMRC) dating back as far as 2017. Named employers have been made to pay back what they owed, and in addition were fined around £7m.
WH Smith was the worst offender, according to HMRC, with the new figures claiming it failed to pay around £1m to 17,607 workers. The retailer blamed this on an error related to its company uniform policy.