Octopus has said the Bulb’s rescue deal will cost the government around £260 million – far less than the £6.5 billion that was previously quoted.

While Bulb was in administration, costs rose to £1.46 billion but the company made gains of £1.2 billion in recent months due to the sharp fall in wholesale prices.

A few months ago, the Office for Budget Responsibility estimated that Bulb’s bailout would cost around £6.5 billion.

The energy supplier, who finalised the agreement to migrate Bulb’s 1.5 customers to its portfolio last month, has also said it could have made a profit last year but decided to keep bills down.

The Octopus head of finance Stuart Jackson said: “We invested heavily in holding customer prices down.”

This decision cost the business more than £150 million in lost revenue, pushing it into a loss.