Understanding our prices
How are my bills calculated?
We want our prices to be clear. This page explains how we apply our prices.
Our credit prices are normally based on two rates: primary and secondary. The primary rate applies to a maximum of 4572 kWh (units) of gas and 728 kWh (units) of electricity that you may use throughout any continuous period of 12 months. Above this volume, we charge at the secondary rate which is cheaper.
Primary rate electricity is charged evenly across the year at a rate of 2 units per day.
Primary rate gas is charged across the 12 months on a seasonally adjusted basis, with more primary rate units being charged in the winter months as follows:
| Months | Maximum units charged at primary rate per month |
| Nov, Dec, Jan, Feb | 882 |
| March | 272 |
| April, Oct | 271 |
| May, June, July, Aug, Sept | 46 |
| Annual total | 4572 |
Why do we charge in this way?
There’s no standing charge on our credit tariffs so the primary rate covers the fixed costs we have to pay in supplying gas to you, e.g. distribution and metering costs.
For gas we charge more units at the primary rate during the winter months to reflect the fact that most customers use more gas in the winter, and to ensure that all our customers pay a fair share to cover our fixed costs.
For electricity we charge the primary rate units evenly throughout the year because electricity use is more consistent across the year.
Does this seasonal weighting apply to all gas tariffs?
No, it doesn’t apply to tariffs where we don’t apply a primary and secondary rate. These are prepayment tariffs, Sign Online 8, Tracker and Fixed Price 2009.
Our prepayment prices include a standing charge which varies from bill to bill according to the period covered by that bill.
If you are on Sign Online 8 your primary rate gas is charged evenly across the year at 381 kWh per month.
If you are on Tracker or Fixed price 2009 your primary rate gas is charged across the 12 months on a seasonally adjusted basis, with more primary rate units being charged in the winter months as follows:
| Month | Maximum units charged at primary rate per month | Month | Maximum units charged at primary rate per month |
| Jan | 630.94 | July | 109.73 |
| Feb | 621.79 | Aug | 109.73 |
| March | 557.78 | Sept | 192.02 |
| April | 448.06 | Oct | 333.76 |
| May | 324.61 | Nov | 470.92 |
| June | 192.02 | Dec | 580.64 |
Calculating bills when we change our prices
When we change our prices we’ll estimate your meter reading as at the date of the price change. To work out this estimate we look at your previous energy usage (or, if we don’t have this information, we use standard industry data for the type of property you live in) and our typical customer’s usage pattern for the time of year. We’ll use this reading to calculate your charges at the old prices up to the date of the price change and at the new prices from that date. You’ll see this calculation on the first bill we send you after we change our prices.
Related questions
- How can I save money on my energy bills?
- I pay by quarterly Direct Debit - am I entitled to a discount?
- What happens to my discount if I change my payment methods or the fuels I take from you?
- Could I be earning a bigger discount?
- Do the new discounts and prices apply to Juice?
