Energyhelpline.com today revealed the UK's hot spots for fuel poverty where 5.1 million households are struggling to pay their gas and electricity bills.
Nearly half of Northern Ireland's households - 44% - are struggling to pay their energy bills followed by those in Wales (32%), Scotland (31%), North East England (23%) and West Midlands (22%). Nearly a fifth of the UK 19% - are facing a daily battle to keep their homes warm.
The independent price comparison service said that high fuel poverty rates are due to a combination of high fuel bills and low incomes. The most expensive areas of the UK are mainly in the north of the country.
Mark Todd, director of the independent price comparison service, said: "It cannot be right that so many people face a daily battle to pay their bills in one of the wealthiest nations on the planet.
"Unfortunately, the problem is only likely to get worse against a backdrop of rising energy prices and the recent extreme weather conditions.
"The harsh reality is that those mainly affected are single people living in single households, including the old and the vulnerable. The fact of the matter is that today's energy market is a dog-eat-dog world - either you defend yourself by shopping around or pay over the odds and fuel suppliers' profits."
The energyhelpline.com research was released on National Fuel Poverty Awareness Day which is run by the charity National Energy Action.
A total of 351,000 Northern Irish households are in fuel poverty - where people spend more than 10% of post-tax income on energy.
People in Scotland and Northern England - where some of the most expensive energy providers are the main suppliers - are also struggling with their bills. North of the border, more than 705,000 households are affected.
Energyhelpline.com's analysts calculate that, based on average winter fuel bills alone, people would have to earn more than the UK average wage of £25,000 to avoid being in fuel poverty.
Todd said: "The industry regulator Ofgem is currently looking at the prices energy firms charge domestic users after concerns that falls in wholesale prices are not being passed on - and their findings can't come soon enough for millions.
"Of course, in a privatised market, energy companies have to make profits for their shareholders. However, the upcoming profit statements from the Big Six providers will give even more relevance to Ofgem's eventual findings because, to many, the retail energy market looks neither competitive nor fair.
"I cannot emphasise enough how energy consumers can make life a lot easier and cheaper for themselves by coming off standard tariffs and switching to online ones. They can potentially make savings of up to £343 a year which has to be good news, especially in such difficult times."