In a statement, Wonga said that having addressed all options the board “concluded that it is appropriate to place the businesses into administration”.
It added: “Wonga customers can continue to use Wonga services to manage their existing loans but the UK business will not be accepting any new loan applications. Customers can find further information on the website.”
Corporate undertakers at Grant Thornton have been appointed to carry out the administration, and it is expected the company will now run Wonga’s loan book.
Customers were being told by the company that, despite the collapse, they are still required to repay any outstanding money.
Over the weekend Wonga said it was “considering all options”, just weeks after shareholders pumped in £10m in a bid to save it from going bust.
Investors in Wonga include Balderton Capital, Accel Partners, Greylock Partners and 83North.
Earlier this month the lender said its struggles were due to a “significant” industrywide increase in people making claims in relation to historic loans.
It blamed claims management companies for the rise, but said it was making progress against a transformation plan set out for the business.
On Sunday, Wonga said the number of complaints related to UK loans taken out before 2014 had “accelerated further”.
“Against this claims backdrop, the Wonga board continues to assess all options regarding the future of the group and all of its entities,” the company said at the time.
Wonga has been criticised for the high interest it charges on its loans and has been accused of targeting those who are vulnerable.
In 2014 the firm introduced a new management team and wrote off £220m of debt belonging to 330,000 customers after admitting making loans to people who could not afford to repay them.
In the same year the Financial Conduct Authority said it would bring in stricter affordability checks to the industry and introduce a cap on the cost of payday loans on the amount borrowed per day.
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