Ofgem back-billing rules: check if you’re owed a refund
If your energy supplier has billed you late, you may not have to pay for energy used more than 12 months ago. Use EnergyPlus to check your situation and compare whole-of-market home energy deals in minutes.
- Understand the 12-month back-billing rule and when it applies
- See what evidence you’ll need to raise a refund or bill-correction request
- Switch to a better tariff once your account is put right
UK households only. We’re a whole-of-market comparison service. We can help you understand the rules and what to ask your supplier—final decisions sit with your supplier/Ofgem framework and the Energy Ombudsman.
Quick claim check: are you affected by back-billing?
The Ofgem back-billing principle (often referred to as the 12-month back-billing rule) is designed to protect households when a supplier has failed to bill you correctly. If you’ve received a surprise catch-up bill, a rebill after an account review, or a bill based on corrected meter readings, you may be able to challenge charges for energy used more than 12 months before the bill date.
Fill in the form and we’ll help you: (1) understand what to ask your supplier, and (2) compare whole-of-market home energy options once your account is corrected.
Tip: Back-billing is different from a general complaint about high prices. It’s about late billing for past usage, usually due to a supplier error (for example, not using your readings or failing to issue bills).
What are Ofgem back-billing rules (12-month rule)?
Ofgem’s back-billing protections are intended to stop households being hit with large, unexpected bills because a supplier failed to bill correctly in the past. In general, if the supplier is at fault for not billing you (or not billing accurately), they’re usually expected to limit what they can recover to the most recent 12 months of energy use.
What back-billing typically looks like
- A “catch-up” bill covering a long period (e.g., 18–24 months)
- A rebill after a meter exchange, smart meter installation, or account review
- Supplier admits they used estimated readings for too long
- Incorrect meter serial number/MPAN/MPRN linked to your account
- Direct Debit was taken, but bills weren’t issued (or were wrong)
What the rule is trying to prevent
If the supplier didn’t send a correct bill in good time, you shouldn’t be punished for their delay. Where the protection applies, you can ask them to:
- Remove charges older than 12 months
- Recalculate your balance and adjust your Direct Debit
- Issue an amended bill statement showing the correction
Important: The exact outcome depends on your circumstances (for example, whether you reasonably could have known you were underpaying). If you’re unsure, start with the eligibility and exceptions section below.
Am I eligible? Common eligibility and exceptions
Back-billing protections are strongest where the supplier is responsible for the delay or mistake. They can be weaker where the customer blocked the supplier from billing accurately (for example, refusing meter access when required) or where the customer knew (or should reasonably have known) the bills were wrong.
Often eligible
- No bills for 12+ months due to supplier issues
- Supplier relied on estimates despite you providing readings
- Billing address/email errors on supplier’s side
- Account/meter points set up incorrectly by the supplier
May be more complex
- You moved in/out and bills cover overlapping periods
- Prepayment meter debt/repayments are involved
- Meter exchange or smart meter commissioning issues
- Supplier says reads were “not validated”
Possible exceptions
- You prevented meter readings or ignored repeated requests
- You knowingly underpaid or ignored obvious billing errors
- Fraud or meter tampering is alleged
- You were correctly billed but didn’t pay
Not sure where you fit? Use the claim check form and we’ll help you frame the right questions for your supplier and understand next steps.
How to claim a back-billing refund or bill correction
If you think your supplier has billed you late, you can raise a complaint and ask them to apply back-billing protections. Keep everything in writing where possible (email, webchat transcripts), and request a clear breakdown of what period the bill covers.
- Ask for a full bill breakdown – dates, readings used, meter serial number, and how they calculated consumption.
- Identify the “old” period – anything more than 12 months before the date they issued the catch-up bill is where protections may apply.
- State you are disputing back-billed charges – request removal/recalculation of charges outside the allowed period where applicable.
- Provide your evidence – photos of meter reads, emails, move-in dates, and any readings you submitted.
- Ask for an amended statement – confirm your new balance, Direct Debit, and any refund/credit due.
- Escalate if needed – if unresolved, you can ask for a deadlock letter and consider the Energy Ombudsman process.
Template wording you can adapt
Use something like:
"I’m disputing charges that relate to energy used more than 12 months before the date of this bill. Please review the account and apply Ofgem back-billing protections where applicable, remove any out-of-time charges, and issue an amended bill and balance breakdown. Please also confirm the meter readings and meter serial number used."
If you’re worried about paying
Even while a bill is in dispute, it’s sensible to keep paying what you reasonably can (especially for recent usage) and keep a record. Ask your supplier for:
- A payment plan based on affordable amounts
- Temporary hold on collections while the complaint is investigated
- Confirmation of what portion they consider “within 12 months”
What evidence helps with a back-billing dispute?
You don’t need a legal dossier, but clear records can speed things up. Here’s what typically helps when challenging late energy bills in the UK.
If you don’t have records: you can still complain. Ask the supplier for their full billing history, the reads they used, and when they believe they first tried to bill you correctly.
After your bill is corrected: compare whole-of-market home energy
Once your supplier has amended a back-billed account (or you’ve agreed what you actually owe), it’s often the right moment to review your tariff. EnergyPlus compares whole-of-market home energy options, so you can see what’s available in your area—including fixes and variable deals—based on your postcode.
Why people switch after a billing dispute
- To move away from poor billing/service experiences
- To find a tariff better aligned to their usage (single-rate vs Economy 7, for example)
- To reduce the chance of estimated billing by providing regular readings/smart meter data
- To reset Direct Debits based on realistic annual consumption
Good to know: If you’re in credit after a rebill, ask your supplier how refunds are issued and how long it will take. Some suppliers can refund to your bank; others may apply credit to future bills.
What we’ll do when you enquire
- Confirm your situation (late bill, rebill, missing bills, estimated reads)
- Help you prepare what to ask your supplier to review
- Compare available home energy tariffs for your postcode
- Support your switch journey (where suitable)
Ready to start? Complete the claim check form.
Common mistakes that can weaken a back-billing complaint
Only speaking by phone
Follow up calls with an email summary so you have a dated record of what was agreed and what you’re disputing.
Not checking the dates
Back-billing is time-based. Ask the supplier to show exactly what period the catch-up amount covers and when they issued the bill.
Ignoring meter details
Incorrect meter serial numbers or mix-ups between MPAN/MPRN can lead to long billing errors. Verify the meter on your wall matches the one on the bill.
FAQs: Ofgem back-billing refund claims
Can my supplier bill me for more than 12 months ago?
In many household scenarios, if the supplier failed to bill you correctly, they should not charge for energy used more than 12 months before they issued the bill. However, exceptions may apply, especially if you prevented accurate billing or could reasonably have known the bills were wrong.
Is back-billing the same as getting a refund?
Not always. Sometimes the outcome is a bill reduction (removing out-of-time charges) rather than a cash refund. If you’ve overpaid due to rebilling, you may be owed a refund or account credit.
Does the rule apply to prepayment meters?
Prepayment situations can be more complex (for example, where debt is collected through top-ups). If you suspect you’ve been charged for historic periods due to supplier error, gather statements and ask for a full breakdown.
What if I moved home during the period being billed?
Ask for a recalculation that aligns to your tenancy dates and opening/closing meter readings. Keep your move-in date, inventory, tenancy agreement, and any handover meter photos if available.
Should I switch supplier while disputing a back-billed account?
Often it’s sensible to get the billing dispute clearly documented first. In some cases you can still switch, but you should understand any outstanding balance and keep a written record of the disputed amount.
How long does a supplier have to respond?
Suppliers should handle complaints within their complaint process. If it’s not resolved, you may be able to escalate (for example, by requesting a deadlock letter and considering the Energy Ombudsman route).
If you’d like help wording your request to your supplier and then comparing home energy deals, use the claim check form.
What UK households like about EnergyPlus
Whole-of-market comparison
We help you see a wider view of available home energy options, so you can make an informed decision after your bill is corrected.
Plain-English support
Back-billing can be confusing. We keep it practical: what to ask for, what evidence helps, and what to do next.
Built around households
This page and form are for UK home energy only (not business). We focus on common household billing scenarios and switching needs.
"I got a catch-up bill covering nearly two years."
EnergyPlus helped me understand what period could be challenged and what to ask the supplier for. After the account was corrected, I compared tariffs and switched.
Homeowner, England
"My bills were estimated for months."
I didn’t know the 12-month back-billing protection existed. The advice gave me a clear checklist and I felt confident raising the complaint.
Tenant, Scotland
Think you’ve been back-billed? Get a quick claim check
Submit the form and we’ll help you understand the Ofgem back-billing rules, what to ask your supplier, and how to compare whole-of-market home energy deals once your account is corrected.
This information is general guidance for UK households and doesn’t replace supplier decisions or formal advice. If you’re in financial difficulty, tell your supplier as soon as possible and ask about support options.
Back to Energy News