Energy suppliers probed on price rise bill chargesConcerns over gas and electricity bill 'overcharging'

18 August 2011

Electricty sparks coming from a hand

Energy companies must explain how they calculate bills after a price rise

Energy suppliers will have to explain to regulator Ofgem how they calculate energy bills after a price rise, amid overcharging concerns.

Ofgem is worried that customers receiving an energy bill spanning both before and after a price increase could be charged too much, if the company disproportionately applies the higher rates to gas and electricity used during the period.

To check that households are being properly billed, it has demanded that all energy companies provide details of how energy price rises are applied to customer accounts.

Energy billing too complex

Which? executive director Richard Lloyd said: 'It's good that Ofgem are looking to tackle this, but the main problem is that energy tariffs and billing are so complex it's often impossible for customers themselves to work out what they should be paying.

'If energy companies were forced to offer simpler tariffs it would be much easier for consumers to work out if they are paying the right price. That might even help the companies regain some consumer trust.'

Find out more about what Which? is doing to help combat confusing energy bills and tariffs.

Avoid energy price overcharging

Unless your energy supplier happens to read your meter on the day your prices change (or you have a smart meter), suppliers have to estimate how many units you have used up until the day of the price increase. That means you could potentially be charged too much for the period before the price rise comes into force.

To avoid this, submit a gas and electricity meter reading to your energy company on the day the price change happens, so it has an accurate reading of how much you've used pre- and post-price increase. The dates you need to do this are listed below for each of the companies that have announced price rises so far.

Energy price hike details

With the exception of EDF Energy, all of the 'big six' energy firms have announced hefty increases in gas and electricity prices. 

  • Npower: up 15.7% for gas and 7.2% for electricity, from 1 October
  • Eon: up 18.1% for gas and 11.4% for electricity, from 13 September
  • Scottish and Southern Energy (SSE): up 18% for gas and 11% for electricity, from 14 September 
  • British Gas: up 18% for gas and 16% for electricity, from today (18 August)
  • Scottish Power: up 19% for gas and 10% for electricity, in effect from 1 August

Check your energy options, and see if you can find a better deal, with Which? Switch, the independent, not-for-profit energy comparison service from Which?. See our energy price rise Q&A for more guidance.

Lower your gas and electricity bills

You can compare energy prices and switch to a new gas and electricity supplier on Which? Switch. People who switched with us between 1 October and 31 December 2013 are predicted to save an average of £234 a year on their bills.

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