Wonga has announced that it is to write off more than 330,000 loans which are more than a month in arrears following an investigation by the Financial Conduct Authority (FCA).
On top of this around a further 45,000 customers who are up to 29 days in arrears will be asked to repay their debt without interest and charges.
The payday lender says it will be contacting all customers by 10 October to notify their particular loan is included in the above numbers.
A spokesman for the FCA, said: “We are determined to drive up standards in the consumer credit market and it is disappointing that some firms still have a way to go to meet our expectations. This should put the rest of the industry on notice – they need to lend affordably and responsibly.”
A notice on the Wonga website explained why the actions were being taken, it said: “You may have already read or heard in the news recently an announcement from the Financial Conduct Authority (FCA) regarding changes to our lending criteria.
“We have been working closely with the FCA to agree additional requirements to our lending criteria, which have been implemented as of the 2 October 2014.
“We have also today committed to a major customer forbearance programme for many existing customers whose loans would not have been made had they been subject to the new affordability criteria introduced today.”