Scottish and Southern Energy is hiking energy prices by around 9 per cent – or an average £119 – from Monday. Meanwhile British Gas is increasing rates by 6 per cent next month and Npower is hiking bills by 9 per cent.
The other Big Six energy suppliers are expected to follow shortly, although E.on will delay introducing any increase until its "no hikes this year" promise expires on 31 December.
Tom Lyon, energy expert at the comparison site uSwitch said: "With SSE's price hike about to take effect and other suppliers edging in the same direction, consumers should be bracing themselves for a round of winter price hikes.
"Consumers will be bitterly disappointed – the pressure of an extra £100 or so on energy bills will leave many buckling and forced to face another winter where they are scared to turn the heating on for fear of the cost."
Energy experts are encouraging people to fixed rates now before the price increases hit. "Anyone hoping to keep their energy bills low in a turbulent energy market should opt for the best value fixed price tariff," said Scott Byrom, energy channel manager at Moneysupermarket.
The cheapest deal is currently offered by OVO Energy, whose New Energy Plan costs £1,088 a year on average, with prices fixed for 12 months. However it's not available in the Scottish Hydro region, where the cheapest option is SSE's Fixed Discount tariff at £1,149.71 on average.
- More about: