Jerome Kirviel, 33, was convicted of abuse of trust, unauthorized computer use and forgery and also banned for life from working within the financial services industry.
The €4.9 billion penalty is the figure the trader is thought to have lost during a series of trades made during the global credit crisis and prompted executives at the French bank to label him as a “terrorist”.
Judge Dominic Pauthe said: “By his deliberate actions, he put in peril the existence of the bank that employed 140,000 people, of which he was a part, and whose future was threatened.”
However, Olivier Metzner, lawyer for Mr Kirviel, said that an appeal against the decision would be launched immediately and described the decision as “unreasonable”.
Mr Metzner said: “He is revolted that those that created him put all responsibility on him. Prison is unacceptable for a man who didn’t make a penny.”
The trader pleaded guilty to the charge of computer abuse but not to those of forgery or abuse of trust.
He will remain free during the appeal.