Check a billEnergy Back Billing Rules: 12-Month Rule, Exceptions and What to Ask
Back billing is not the same as “my bill is huge”. First identify whether the supplier is recovering old charges, correcting estimates or sending a normal catch-up bill.
Use together
The short answer
Back-billing rules usually protect customers from being charged for energy used more than 12 months ago when the supplier failed to bill correctly and the customer did not obstruct billing. But many large bills are actually catch-up bills based on previous estimates. You need to separate those two before complaining.
Rule and exception matrix
| Scenario | Likely issue | Best next step |
|---|---|---|
| Supplier is billing usage from more than 12 months ago | Possible back-billing protection | Ask them to identify old charges and the rule they rely on. |
| Previous bills were estimated and now actual read corrected them | May be catch-up rather than protected back billing | Check reading history and whether statements were sent. |
| You did not receive accurate bills for over a year | Strong back-billing review trigger | Use the not-billed-for-over-a-year page and template. |
| Meter access or readings were blocked | Protection may be weaker | Check what evidence the supplier has and whether you cooperated. |
| Supplier already billed the amount before | May not be new back billing | Ask for statement history and balance breakdown. |
What to ask the supplier
Which period is old?
Ask them to separate charges by supply period.
Which readings changed?
Get estimated and actual reading history.
What rule allows the charge?
Ask them to explain any exception they rely on.
What amount is disputed?
Separate undisputed recent use from disputed old use.
Focused back-billing question
Please also explain whether you consider those charges protected by the back-billing rules and, if not, which exception you rely on.
Until this is explained, I dispute the older portion of the balance and ask that collection activity on that portion is paused.
Frequently asked questions
Is every catch-up bill back billing?
No. A catch-up bill can happen when estimates are replaced by actual readings. Back billing is specifically about older unbilled or incorrectly billed usage.
Can standing charges be included in back billing?
Back-billing issues can involve both usage and standing charges if they relate to the old period. Ask the supplier to break down the amount.
Should I ignore the bill while disputing it?
No. Ask what undisputed amount should be paid and keep the disputed older portion separate in writing.
Official sources used for this page
BillDecoded translates official process and billing information into practical checks. It is not affiliated with the Ombudsman, Ofgem, Citizens Advice, Which? or any supplier.