British Gas was the first big six supplier to announce a price rise this year, and its 5.5% increase comes into effect for 4.1 million customers today (29th May).
But it's not just British Gas customers that should now be shopping around.
Those coming off fixed deals face a double price rise as five of the big six suppliers and nine smaller energy companies have also raised their rates this year.
27 suppliers have 95 fixed deals expiring this May and June, after which their customers could be rolled onto expensive standard variable tariffs.
To make matters worse, there are a number of price rises coming into effect that will see the jump in costs from a fixed deal to a rollover tariff even greater.
Eight of the 27 suppliers with deals ending this month have announced price rises so far in 2018. Before the price rises, customers with a big six supplier and a fixed deal ending would have faced bill hikes of an average of £181 (19%), but after price increases this has soared to £226 or 23%.
If no action is taken to switch plans, the customers facing the biggest hikes are those with Go Effortless Energy (£401), npower (£399) and Scottish Power (£365).
Ofgem’s rules allow customers to switch suppliers without paying exit fees from 42-49 days before their plan end date, so consumers are free to shop around without penalty.
If you haven't switched in around 12 months, it's worth taking a look at your plan end date on your bill. Once this date comes around, you'll be rolled onto a plan of your supplier's choosing, this includes pricey standard variable tariffs.
Run a comparison to see how much you could save by choosing a new fixed plan. All you need is around 10 minutes, your postcode, and a recent bill. If you need help finding any information on your bill such as your kWh usage or plan end date, our guide can help: How to switch: step-by-step.
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