MILLIONS of households could see their energy bills shoot up by as much as £439 as hundreds of fixed-price deals come to an end in July, August and September.
Customers who do not move to a cheaper deal will be automatically rolled onto default standard variable tariffs (SVTs), which usually provide the worst value.
The average increase will be £269 per affected household, but people who get their energy from iSupply, Ovo and Green Network Energy will see even greater hikes of £439, £367 and £342 respectively, uSwitch calculated.
The comparison site warns the changes will add £426million to the energy bills of 1.6million households if they do not switch.
There are 276 tariffs expiring in July, August and September from 37 suppliers and many of those affected are likely to have chosen their fixed deal last summer.
How to switch and save
ALL all you need to do to avoid paying more is switch to a new deal – which should only take you ten minutes.
You may be able to get a better offer through your existing provider, but you’ll generally get an even bigger discount if you shop around.
Using a comparison site, such as Comparethemarket.com, uSwitch.com or GoCompare.com can help you find the best deal on the market.
You’ll need your postcode, the name of your current supplier and the name of your current tariff.
It’s also handy to have a recent bill so you can see your usual energy usage.
You’ll want to consider price, but you may also wish to look at factors such as customer service or environmental credentials.
Once you’ve chosen a new deal, switching is easy – especially if your new provider is signed up to the Energy Switch Guarantee.
This means that your new supplier will handle the whole switchover for you, and guarantee that everything will be sorted within 21 days.
Once you’ve swapped over, you have 14 days to make sure you’re happy, and if not you can switch back.
Your gas and electricity supply continues as normal during the switch.
At least 44 energy companies have already increased the cost of their SVTs by up to 17 per cent this year, following Ofgem’s decision to raise the level of the energy price cap in April.
The cap tells energy providers the maximum amount they can charge for standard variable tariffs.
Ofgem is expected to announce that the price cap will decrease by around £80 next month from £1,254 on average, but this lower rate will not take effect until October 1.
Even after the cap is reduced, customers who stay on default tariffs are likely to be overpaying by around £300 a year.
Rik Smith, energy expert at uSwitch.com, said: “Energy bills might not be front of mind just as everyone is about to head off on their summer holidays.
“But over one-and-a-half million households could be in for a nasty shock when they get home if they don’t act now.
“There was more than one price rise a week during 2018, and many of those who switched to escape the onslaught then are now seeing their fixed price plans coming to an end.
“People who switch to a fixed deal this time should also sign up for a reminder to alert them when their plan is next due to expire.”
Theresa May’s energy price cap was branded a flop as the big six rip-off gets worse, figures show.
Energy firms including British Gas and E.on are “exploiting” loyal customers by charging them £324 a year extra.
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