Official figures by the Office for Budget Responsibility (OBR) show that the cost of keeping the energy supplier afloat has soared to £6.5 billion.
Handling the company in 2022-23 will cost an extra £4.6 billion, the OBR has confirmed.
In its earlier forecast, the non-departmental public body estimated that the bailout would cost £2.2 billion over two years.
In response to the paper’s findings, Andy Prendergast, GMB National Secretary, said: “The fact bailing out one failed energy company has cost £6.5 billion is yet more proof the attempt to use the markets has been an unmitigated disaster.
“How Ofgem allowed a company like this to rack up such unsustainable debt beggar’s belief. In times of unprecedented hardship, costing £230 on bizarre ideological theory is utter stupidity.”
A few days ago, Octopus signed the deal to buy Bulb’ and add the company’s 1.5 million customers to its existing portfolio of around three million accounts.