E.On has said it will step in to help a licensee whose electricity bills shot up from £414 a month to £2,700.
The total bill for the Saddle Inn in Lea, Preston, now stands at £15,811, as Graham Rowson, licensee of the Daniel Thwaites pub, has refused to pay for five months.
He joined E.On in January last year after agreeing to a contract over the phone with monthly payments of £414.
After five months the charges began to creep up and eventually hit £2,700 five months ago.
Rowson has refused to pay ever since, saying he has been in consistent contact with E.On to complain since his bills began to increase in May 2010.
"By my calculation, the very most they should be charging me is £2,300," Rowson said.
Around five months ago E.On sent out a debt management consultant, who lodged a complaint on Rowson's behalf. The complaint was removed soon after and Rowson did not hear anything further.
The Saddle Inn has a single meter reading, which E.On blames for the rising bills as it cannot record separate energy rates for night time and weekends.
Most recently, E.On wrote to Rowson advising him to speak to the energy ombudsman, which he had already done.
However, following a Morning Advertiser inquiry, an E.On spokesman said: "We are aware of the problems around Mr Rowson's bill, which appears to have been partly caused by a meter issue. We are working with Mr Rowson to try and find a mutually acceptable way forward and will also be changing the meter."