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British Energy ComplianceUTILITIES · ADVISORY · ASSURANCE
Free tool

Back-billing recovery calculator

Estimate how much of an unexpected catch-up bill may be unrecoverable under Ofgem’s 12-month back-billing rule (SLC 7A for domestic, SLC 21BA for microbusiness).

How the rule works

Since 1 May 2018 (domestic) and 1 November 2022 (microbusiness), Ofgem has prevented suppliers from charging customers for energy used more than 12 months before the bill was issued, where the supplier was at fault for the missed billing. The rule sits in the standard licence conditions and is enforced by Ofgem.

Enter the date of your last accurate bill, the date of the new catch-up bill and the amount, and the tool will pro-rate the charges across the unbilled period and tell you the slice that should be written off.

Microbusiness gate (tick any that apply)

What this does NOT determine

Whether the supplier was actually at fault, whether prior reads were estimated rather than actual, whether the energy was in fact used, or whether the contract permits a higher unit rate for the back-billed period. A formal case review confirms these from the meter audit trail and correspondence.

Request a free written case review See the back-billing letter template
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