Complaints over British Gas have more than doubled since last year, with billing largely to blame, Energywatch says.
Hundreds of BBC News website readers have sent us their experiences, a selection of which appear below.
I was on the telephone to British Gas for 55 mins on hold last night. Then when I spoke to someone I had the wrong number and spent a further 28 mins on hold again. All this in an emergency situation! RIDICULOUS. How do I complain when the website 'contact us' section is inaccessible? What a kick in the teeth for high-paying customers!
Nicola Butcher, Doncaster, England
I received a call from a British gas call centre in January regarding the supply of electricity. The woman promised to not only save me money but that the bills would not rise over the coming year. To my horror the first bill came in and it was £74 more expensive than my monthly bill with Southern Electric.
David Jackson, Witney, Oxon
I've had an ongoing dispute with British Gas since we moved into our property ten months ago. I have given their billing department our gas meter readings at least eight times and their system still fails to send me a correct bill. I have sent a complaint to their customer services department. On the day I received a letter from customer services saying this matter was being looked into someone turned up at our house to turn off our gas! I was then billed £20 for this! I was contacted a month later by customer services and asked to give them the details again. I called last week because over a month had passed. They had NO record of any of the information I had given. We have not paid any money towards our gas account because we have no faith in their system.
Miss Curigwen Haas, Howden, Goole, England
We haven't had an electricity bill from British Gas since we moved into our new home in July ! When we moved in they kept telling us that they didn't supply our electric. I kept telling them they did! Then in January they got in touch to tell us they do supply our electric. It is still not resolved today!
Daniel Rathe, Welshpool
British Gas are debiting my account to the sum of £98 per month and building a large credit. I have asked them to reduce the amount but to no avail.
Eric Lawrence, Edmonton London
I was trying to pay my British Gas bill for 9 Months. No one seemed to take any notice when I phoned them and said I wanted to pay and avoid a even larger bill. Now after nearly ten months and with another bill nearly due I have finally got a bill for the whole period which I am having problems paying. They have put me in the very position I was trying to avoid.
Daniel Jones, London
British Gas are sending me my tenant's bill. I told them the date I moved out and my tenant moved in. I have called them many times and they have put me in a queue which cost me money and they still don't solve the problem. Call durations I have endured are 70 mins, 60 mins and 45 mins. My tenant called them as well.
Shakil Ahmad, Burton on Trent, UK
I have been with British Gas for my electricity since August 2006 and I have not yet received any bills. I have phoned at least ten times and written twice. I still have no bill and am getting very frustrated phoning them up. I do not know what else I can do.
Patricia Wilton, Waltham Abbey, Essex
I moved into my current property in Feb 2006. I have been trying ever since to get BG to provide me with a correct bill. In July 06 I switched gas supplier but still BG are billing me for gas used before i moved into the property. I have called them more than 20 times. Each time I am given assurances that this time it will be sorted. Only yesterday I received another letter with a final demand for money which I do not owe and a statement that debt collectors are on there way!
Phil Molyneux, Lancaster, England
As a long-time sufferer of British Gas' incompetence, I have seen this coming for ages. An example of their shoddy management was earlier in the year when, in response to a huge loss of customers, they announced a price cut. They just couldn't see that their problems were of a customer service nature rather than a pricing issue. I wouldn't go back to them now if they gave their gas and electricity away for nothing. I could, however, offer them some professional advice on how to run a company properly.
Martyn Pitt, Gloucester, England
I had continual problems with British Gas. I finally moved to another service provider. It's not just an inability to process the billing properly; but the multiple promises made to follow up and correct the multitude of errors made by the customer service team - all of which were not followed up. I would have to start over everytime I rang British Gas. Twice I had to involve Energywatch as I was at my wits end. Never would I ever use British Gas as a provider again and have made sure I have told my friends the same.
British Gas boast that so many customers per day are returning to them. Is there any wonder when they don't give them a choice. Several times we got letters to say we had been changed, without our permission, from Powergen to British Gas. On one occasion they did send letters saying that they were sending an engineer to do this, twice we phoned to say we didn't want them to, next thing there is an engineer at the door to swap us over. When boasting about how many customers are going back to them, maybe they should also tell us how many of them are by choice.
Damian Cox, Lincoln
I advised British Gas of both Gas and Electricity final readings on completion of a property move back in December 2005. Both accounts were in credit and refunds were due. Have just received a refund on my electric bill and am still awaiting my final gas refund. This despite numerous calls to customer service.
Richard Edwards, Farnborough, Hants
Why is it when gas and electricity bills are supposed to be estimated that they are always massively overestimated and never underestimated. When we phone up with a correct reading we are held in a queue, sometimes for over 15 minuets, at ten pence per min + vat. Being an old age pensioner it becomes very expensive. Not like the old days is it?
Anthony Roberts, Upminster
We recently switched from British Gas to another supplier as they have constantly ignored our requests to change from a key meter to a monthly bil in our rented flat. There is no money outstanding and for a long time we had bills saying we were in credit. Upon leaving them they have now sent us a bill for £60 saying we have not payed enough for our electricity! Amazing seeing we are on a pre-pay meter!
Jonathan Price, London, UK
I am still experiencing problems with both British Gas and npower. I have been in touch with energywatch and the problems are ongoing. I switched suppliers in December 2006 and thought everything had gone ahead okay until I recieved two sets of bills for Gas. Despite numerous phonecalls I have been told by each company it was the others fault. I now have legal proccedings threatened.
Caren Horsfield, Selby North Yorkshire
I have spent the last four months trying to persude British Gas to use the full address for another of their customers who lives in a village that I moved from six months ago. Because of their failure to use his full address, his gas bill is being erroneously redirected to me by the Post Ofice. Despite repeated phone calls from myself and my wife, the company is now threatening to cut him off over a problem entirely of their own making.
Ron Smith, Fleet, Hants