The glut of gas and electricity price rises by four of the UK's 'Big Six' energy suppliers is set to hit energy customers in the pocket.
However, according to the Daily Mail, many customers on the cheapest deals will actually face rises far higher than those advertised.
For instance, Scottish Power, which has already introduced the rises to customer's bills, said average customers would face gas price rises of 19 per cent and electricity rises of ten per cent.
It said its customers on dual-fuel tariffs would essentially face a 17 per cent rise, which works out around Â£174 per year.
In reality, though, customers on the Online Saver 10 tariff will see their bills increase by Â£308 - or 36 per cent. Customers on other online tariffs, 11 and 12, will face rises of 30 per cent, which is around Â£267.
The same applies to British Gas customers, who were told average bills would rise by 18 per cent and 16 per cent for gas and electricity respectively - or around Â£190 for standard dual-fuel bills. However, their online tariff customers will actually see rises of around 21 per cent.
E.ON's customers have been told gas and electricity prices will rise by 11.4 per cent and 18.1 per cent for electricity and gas - their dual-fuel customers will have to pay Â£157 extra a year. But its SaveOnline customer,s on tariffs three to six, will actually face rises of around 19 per cent, or Â£169 a year.
The Government has already suggested that consumers use energy comparison websites to find cheaper bills - with customers being warned that the only have 30 days from the date of the announced price rises to switch supplier without having to pay a penalty charge for leaving their current provider.
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