Amy Davies, 33, had wanted the Glasgow tribunal to award her more than 700,000 for lost career opportunities and damages against National Australia Group Europe Ltd (NAGE), owner of the Clydesdale and Yorkshire Banks.
Ms Davies claimed she was unfairly sacked from her 67,000 job after exposing an apparent discrepancy between bank-account ledgers, which she said ran into millions. NAGE denied her claim, blaming her behaviour and lack of people skills for her dismissal.
The tribunal rejected her claims of unfair dismissal and breach of contract. Ms Davies was awarded 2,961 holiday pay which the bank had conceded.
The bank said an independent investigation found no "large hole in the accounts'' but there had been accounting errors.