They are among 518 employers across the UK who owe their workers more than £7.4 million, according to the government.
The named businesses have since paid back what they owe and faced financial penalties of up to 200 per cent of their underpayment.
The investigations by His Majesty’s Revenue and Customs (HMRC) concluded between 2015 and 2022.
Details of how much each business owed and how many workers were affected were also revealed.
The worst offender in Croydon was PizzaExpress restaurants, which failed to pay £760,701.61 to 8,470 workers.
Another major offender was Day Lewis PLC, a pharmacy on Peterwood Way, which short-changed 604 workers by a total of £82,819.47.
Other businesses named and shamed include Managing Care Ltd on High Street (£21,834.52 to 83 workers), MA Bureau Ltd (£13,226.91 to six workers), and Lashes Nails and Brow Ltd (£9,074.84 to three workers).
Sparkle Cleaning Ltd on Addiscombe Road was named and shamed for failing to pay a total £2,7392.94 to 25 workers.
Penge Car Care was the seventh Croydon business to be named and shamed.
The car wash in South Norwood failed to pay a total of £682.48 to two workers.
Minister for Employment Rights, Justin Madders, said: “There is no excuse for employers to undercut their workers, and we will continue to name companies who break the law and don’t pay their employees what they are owed.
“Ensuring workers have the support they need and making sure they receive a fair day’s pay for a fair day’s work is a key commitment in our Plan for Change.”
Baroness Philippa Stroud, chair of the Low Pay Commission, added: “We welcome today’s publication.
“Underpayment leaves workers out of pocket and disadvantages the majority of employers who do abide by the rules.
“These naming rounds play an important part in ensuring that all workers receive their full wages and that they are aware there is support for them to ensure that they do.”
The government has also announced that the National Living Wage and National Minimum Wage will be increased as part of its Plan for Change to support workers and boost productivity.
The government has also extended the current relief for high street retail, hospitality, and leisure properties, providing a 40 per cent reduction on their liability, and frozen the small business multiplier.
