Guides › Energy and Water Bills › Energy Back-Bill: Do I Have to Pay for Energy Used Over 12 Months Ago?
Energy Back-Bill: Do I Have to Pay for Energy Used Over 12 Months Ago?
Energy suppliers generally cannot charge you for energy used more than 12 months before the new bill, unless you were already billed for it. The limit does not protect you if you acted unreasonably, for example by blocking access to the meter. If your supplier will not remove the charges, the Energy Ombudsman is free.
At A Glance
Your Rights
What the rules say, with a link to the official source for each.
The 12-Month Back-Billing Limit
The 12-Month Back-Billing Limit
Energy suppliers generally cannot charge you for energy used, or standing charges, more than 12 months before the new bill, unless you were already billed for that amount. This covers households and microbusinesses. source
When the Limit Applies
The 12-month limit also applies if you asked for an accurate bill and did not get one, you were not told about the charges through a statement of account, or your Direct Debit was set too low to cover what you used. source
When It Does Not Protect You
The limit does not protect you if you acted unreasonably, for example by blocking access to the meter, ignoring payment requests or stealing energy. source
If Your Supplier Will Not Remove the Charges
The Energy Ombudsman
If your energy complaint is not resolved within 8 weeks, or you get a deadlock letter, you can take it to the Energy Ombudsman. It is free and impartial. source
Time Limit for the Ombudsman
After you get a deadlock letter, you have 12 months to take your complaint to the Energy Ombudsman. source
Time Limits to Know
Miss a deadline and you can lose a right. Check the dates on your own paperwork.
- 12 monthsEnergy back-billing limitGenerally 12 months before the new bill
- 8 weeksEnergy complaint to the Energy OmbudsmanAfter 8 weeks with no resolution, or on receiving a deadlock letter
- 12 monthsGo to the Energy Ombudsman after a deadlock letterFrom the date of the deadlock letter
Steps to Take
Step 1 of 5
Check the date of the bill and the period it covers.
Step 2 of 5
Gather your meter readings and past bills.
Step 3 of 5
Write to your supplier and ask it to remove the charges older than 12 months. Use the ready-to-use letter further down this page.
Step 4 of 5
Keep answering your supplier’s requests, such as for meter readings, while it looks at your complaint.
Step 5 of 5
If it is not sorted within 8 weeks, or you get a deadlock letter, go to the Energy Ombudsman.
(Tap the numbers to reveal steps)
Where to Go If It Is Not Put Right
Your options, in order, and when each one applies.
Your Energy Supplier's Complaints Team
Always start here, in writing.
Energy Ombudsman
After 8 weeks with no resolution, or when you get a deadlock letter.
Good to Know
Small things that make your complaint stronger.
The limit covers households and microbusinesses. Other business customers have different rules.
Ask your supplier for a complaint reference number and keep a copy of everything you send.
Ready-to-Use Letter
Copy this, fill in the square brackets and send it in writing. Keep a copy and proof of sending.
Subject: Back-bill dated [date], account [number] Dear [supplier], I have received a bill of [amount] dated [date] covering [period]. Part of this relates to energy used more than 12 months before you told me about the charge. I understand that, under Ofgem rules, I should not be charged for that part where the supplier did not bill me accurately or tell me about the charges. Please remove charges older than 12 months, confirm in writing, and pause any debt action while this is looked at. If you disagree, please send your final response so that I can go to the Energy Ombudsman. Yours sincerely, [Your name]
Want Help?
If you would like one of our team to look at your problem, our initial case review is free. We cannot guarantee any outcome and we do not give legal advice.
Lead reviewer
Luke Marley
Founder and Lead Reviewer
Luke founded CPUK in 2026 after seeing how hard it is for ordinary people to get problems with companies put right. He oversees our guides and checks them against official sources.
Research by Katie Burt, Co-founder and Operations Lead (17 years in the care sector, including managing services for vulnerable adults), and the CPUK Research Team. Researched with AI-assisted research tools, then checked and corrected by our team.
Last checked: 12 October 2026. We are not paid by the companies we write about. Adverts never affect our guidance. Read our editorial policy.
Sources and official links
- energyombudsman.org/advice-for-consumers/what-is-back-billing Checked 12 October 2026
- energyombudsman.org/faqs Checked 4 October 2026