Jonathan Revill made a profit of £5.6m from the scam while working at an energy company based in Leeds and blew most of it betting online.
The 38-year-old was able to pay cash for his £500,000 home in West Yorkshire and would gamble as much as £300,000 on a single sporting fixture.
Even after his arrest, the father-of-one accessed more than £20,000 from his betting account and lost it all in one evening.
His wife and child knew nothing of his secret addiction until he was arrested and they learned they would lose their home.
Revill pleaded guilty to four offences of fraud and one of transferring criminal property at Leeds Crown Court yesterday.
He stole the money from GDF SUEZ, one of the world’s largest companies, while he worked as a service delivery systems manager at its subsidiary business, GDF Suez Energy, based in Leeds. The Leeds office alone has an annual turnover of £1bn.
Revill’s annual salary was £55,000 plus bonuses and he received a £400-a-month car allowance.
Mehran Nassiri, prosecuting, told the court Revill faked signatures to order more than £18,9m worth of computer equipment from a supplier over a three-year period, which he arranged to be delivered to his home in Huddersfield or to a storage unit.
He then sold it on to other companies or through eBay, with the cash made then paid into Revill’s bank account.
Revill, of Marsh Lane, Huddersfield, had submitted 104 invoices for equipment before auditors uncovered the fraud in May.
After his arrest he was granted bail on the condition he stopped gambling and sought help.
But just days later, on June 2, he accessed cash in an account based in the Isle of Man and gambled it in a single evening.
The Yorkshire Post understands it was used to place bets on tennis, football and baseball over a three-hour spree on the Bet365 site. These included high-value bets on the French Open, including a £11,250 bet on Gilles Simon to beat Roger Federer, which he lost. He then won £27,757 from a £13,062 stake on England and Brazil to be 0-0 at half time, before losing £17,757 after betting on Brazil to win the match.
Benjamin Hargreaves, mitigating, said: “Winning or losing didn’t matter.”
The barrister said at one stage during the deception Revill had as much as £3m in his account and added: “He accepts over the last 10 years a gambling problem has got bigger and bigger.”
Jailing him, Judge Geoffrey Marson, QC, said: “This was a vast amount of money.”
Det Chief Insp Mark Griffin, of West Yorkshire Police, said Revill had abused his position to defraud his employer on a “massive scale” adding: “His actions have destroyed his life and affected a number of businesses. This case clearly highlights the very serious consequences of gambling addiction.”
A GDF SUEZ spokesman said the company was conducting a thorough internal review and thanked police for “diligent” work.
He said customers would not be affected, adding: “We expect the financial impact on the business will be mitigated through insurance.”
The Government announced plans last year to tighten up its regulation of online betting by extending the powers of the Gambling Commission which will mean all websites offering gambling to British consumers must hold a Commission licence and offer player protection tools such as spending limits.