More than a quarter of people (26 per cent) surveyed by Consumer Focus said they would not consider switching again, with 43 per cent of vulnerable or poorer households saying they would not change supplier in the future.
Almost half (46 per cent) of customers who had problems switching had issues closing the bill with their old supplier, 29 per cent suffered delays in the switching process, and 22 per cent reported poor customer service.
Gillian Cooper, head of energy retail at Consumer Focus, said: “Without additional measures to improve the switching process and other issues, many consumers will continue to pay over the odds for their energy.”
Angela Knight, chief executive of Energy UK, said the energy companies were “committed to continuous improvement in the switching process”, but added “this research shows that 80 per cent of customers who switch energy supplier are satisfied with the process, which is good to see.”