Householders who have cranked up the heating over the past few weeks can expect to pay an extra £70 on their January fuel bill, according to price comparison website energyhelpline.

Sub-zero temperatures have forced many people to run their heating for longer than normal, and it is feared some will face unmanageable bills as a result.

Energyhelpine said it expected the average household dual fuel bill to rise to £226 for this month – a £70 rise.

It said the typical heating and hot water bill increased by 28p for every 1C fall in the outside temperature. With temperatures around 7C colder than normal this was an additional cost of £1.96 a day, which over 31 days would add up to £60.76.

On top of this it expected electricity usage to increase by 15% as a result of more people staying in, which would add £9 to average monthly bills.

British Gas said it was too early to say what impact the freezing weather would have on gas bills.