Back-Billing

Back-billing is the practice of a supplier issuing a bill for energy used in a period earlier than the most recent settled bill — typically because of a meter-read failure, a billing error, or a delayed transfer. UK rules limit how far back a supplier can recover such charges where the customer is not at fault.

The Ofgem Standard Licence Conditions provide:

• Domestic and microbusiness: a supplier cannot recover charges for energy used more than twelve months before the customer was first told of the issue, where the customer has not previously been billed correctly.
• Larger non-domestic: no equivalent statutory back-billing limit, but the contractual position and limitation periods under general law still apply.

The rule does not prevent legitimate billing of energy actually used; it limits the recovery period where the supplier has failed to bill correctly within twelve months. Back-billing disputes are one of the more frequent reasons businesses escalate to the Energy Ombudsman, and the rule is routinely misapplied by suppliers in microbusiness cases — particularly where the customer status was never asserted or where the issue arose during a change of tenancy or supplier transfer.