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Estimated or Wrong Energy Bill
If your energy bill is estimated or wrong, take a meter reading and ask your supplier in writing for a corrected bill. Energy suppliers generally cannot charge you for energy used more than 12 months before the bill. If your complaint is not resolved within 8 weeks, or you get a deadlock letter, you can take it to the Energy Ombudsman, which is free.
At a Glance
Your Rights
What the rules say, with a link to the official source for each.
Energy Bills
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
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 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
Steps to Take
Step 1 of 5
Take a meter reading and a dated photo of the meter, and keep your bills.
Step 2 of 5
Give the reading to your supplier and ask for a corrected bill. Check the bill against your reading and your Direct Debit amount.
Step 3 of 5
If a bill covers more than 12 months, say in writing that the 12-month back-billing limit applies and ask for the charge to be removed.
Step 4 of 5
Complain in writing, say what you want, and keep copies. Our free letter templates can write it for you.
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.
Ask for a complaint reference.
If you are struggling to pay, tell your supplier early and ask about support. Do not ignore it.
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