The energy regulator has warned gas and electricity suppliers they must adhere to its code of practice on billing, as some of the information they provide may not be clear or accurate.
In a letter to industry association Energy UK, Ofgem stated while it has found no evidence of systemic errors or deliberate attempts to overcharge customers, many customers were unsure how charges are calculated if there is a price change within their billing period.
It reminded the body that all suppliers that are party to Energy UK's Code of Practice for Accurate Bills have a requirement to use all available information to produce "accurate, clear and timely" bills.
Ofgem urged the industry organisation to check that its members are following this code, warning that the regulator may take action in the future against any suppliers it deems to be non-compliant.
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