Monzo suffered £114.8 million in pre-tax losses last year despite growing revenues. 

The digital bank’s accountants say there is ‘material uncertainty’ over the future of a company which is also being investigated by the Financial Conduct Authority over potential breaches of financial crime regulations. 

Monzo said it was complying fully with the FCA’s investigation, which it revealed in its annual report. “Over the past year we have made major investments in our controls in this area as a priority and will continue to invest heavily in this part of the business,” said a spokesperson. 

“The FCA’s investigation remains at an early stage. Our operations are unaffected and we remain committed to serving our customers. 

“This could have a material negative impact on our financial position, but we won’t know when or what the outcome will be for some time.” 

Monzo is one of several banks to which the financial watchdog sent letters in May, warning of failings in anti-money laundering controls. 

Monzo’s losses are at a similar level to the year before, but revenue for the last year is twice as high after growing 18% to £66m. Monzo says it expects to be profitable by 2022 as deposits increased from £1.4 billion to £3.1bn last year. 

The challenger bank, which added a million new customers last year, now has 200,000 paid subscribers to its premium accounts and holds 77,000 business accounts. It now has five million customers in all.