The new changes will differ depending on where in the country people live and how they pay for their gas and electricity.
The hike will be worst for those households in North Wales and the Merseyside area who pay for their electricity after the fact, and not by direct debit. Their bills are set to rise by more than £5 per month between January and April.
Bills will also go down for some households. Those in the north of England will likely pay around £3.90 less per month from Sunday.
The changes are made to the amount that energy suppliers charge per unit of gas and electricity they supply.
These changes come into force at the beginning of January and last until the beginning of April.
The changes are small compared with recent major swings in how much the Government’s energy price guarantee, which caps per unit charges, still applies.
The monthly charges are calculated based on what the average household uses in a year – 4,200 units of electricity and 12,000 units of gas – and assume that usage is spread evenly over the year.
As people use more gas during the winter, the actual figures are likely to be somewhat larger.
People who pay on so-called standard credit, which means they get an invoice every month or quarter and do not pay by direct debit, will be the worst hit by the changes.
Their bills are set to go up by around £3.90 per month on average, ranging from around £2.60 in the north of England to £5.60 in the Mersey and North Wales region.
Prepayment meter customers will see an average bill increase of £1.50, while those who pay by direct debit will see an average increase of just two pence.
The system works differently for customers on certain types of tariff, such as Economy 7.
For these customers “suppliers have flexibility to apply slightly different discounts to the individual rates within the tariff, helping to balance out the reduction of more expensive day rates with cheaper night-time electricity rates. Each supplier will approach this differently”, the Government said.
The Ofgem price cap has always been set at slightly different levels based on where someone lives and how they pay.