Homeowners with pre-payment meters have been overcharged by their energy suppliers by around £500 million over the past three years, according to an expert body.
The National Housing Federation (NHF) produced the figures from Ofgem findings and reported that customers who have been overcharged could be in a position to get their money back from their supplier.
Nearly 15 per cent of UK households use pre-payment meters and as many of these families are living on a low income, the effects of overcharging can be significant and those affected are more likely to be in fuel poverty as a result.
David Orr, chief executive of the NHF, said: "As a way of compensating pre-pay customers for the historic overcharging, Ofgem has a moral duty to go beyond the EU directives, and force the energy companies to equalise pre-pay meter prices with those for quarterly bills."
All the UK's major energy companies increased their prices throughout the course of last year and industry experts warned that fuel poverty figures may have increased as a result.
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