One in five business energy bills contain mistakes, from incorrect rates to meter reading errors.
That could be costing firms around £500 million on their energy bills due to errors and inaccuracies across the supply chain, according to new research.
Thousands of business energy invoices were analysed to find the most common errors and forecast the scale of the issue.
It revealed the retail and leisure sectors were most likely to be paying inaccurate charges – £200 million – due to their complex portfolio of sites with multiple meters and frequently changing tenants.
It found the public sector could be overpaying by £112 million, the property sector by £78.5 million and the manufacturing industry by around £65 million.