Ofgem has proposed limiting suppliers from back-billing customers for energy used more than 12 months ago.
It mainly results from suppliers using estimated bills until they take an actual meter reading, which may show the customer’s energy usage is higher than expected.
Suppliers then send a ‘catch-up’ bill to recover the difference, sometimes resulting in large amounts being owed.
In 2007, energy firms signed up to a voluntary commitment not to back-bill domestic customers for energy used more than 12 months previously if the supplier is at fault.
However, Ofgem is concerned the voluntary principle is not being applied consistently and not all suppliers have appropriate back-billing protections in place.
It comes as the energy supply market has expanded form 11 suppliers in 2007 to more than 50 currently.
Senior Partner Rachel Fletcher said: “Getting billing right is an essential part of customer service but when things go wrong, we want to ensure that all customers benefit from the same protection against back-billing.
“We cannot be certain that this is the case now under the voluntary commitment. We expect suppliers to put their customers first, which is why we are proposing a new enforceable rule to provide this protection.”
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