Around four million households on pre-payment meters will see their power bills slashed and providers will have to share customer data to allow rivals to offer them better deals under proposals announced by the energy watchdog.
The Competition and Markets Authority (CMA) said British households could have been overpaying by around £1.7 billion a year and added that the Big Six providers have been taking existing customers - 70% of whom are stuck on standard variable rate deals - for granted.
In its long-awaited report, the CMA said it wants to set a temporary price cap for low income and vulnerable customers who have pre-payment meters, and plans to launch an Ofgem-controlled database allowing rival suppliers to offer those on standard variable rates (SVRs) for three years or more better deals.