Nobody at the Commonwealth Bank seemed overly concerned when customer Matthew Pearce told staff the bank had given him $123 million by mistake.

They just laughed and shrugged their shoulders, Mr Pearce told Channel Nine.

'I was pretty shocked': Matthew Pearce and his surprise bank balance. Credit:Channel Nine

The Melbourne glazier awoke in November last year to find his phone telling him that a small personal bank balance had somehow risen overnight to the princely sum of $123,456,789.01.

"It [his banking app] actually gave me the option to transfer the money and BPAY it, so I could actively transfer money into someone else's account," he told Channel Nine.