Energy billing errors:
your rights and how to claim
Overcharged, hit with a surprise back-bill, or getting estimated bills that do not match your usage? Here is exactly what you are owed and how to get it.
Energy suppliers cannot charge you above the Ofgem price cap, cannot back-bill you for energy used more than 12 months ago (if the delay was their fault), and must follow a formal complaints process. In 2026, 10 suppliers were ordered to pay £7 million in compensation to 34,000 households after overcharging due to a billing error. If you have a billing dispute, complain in writing to your supplier first, then escalate to the Energy Ombudsman if unresolved after 8 weeks.
£7 million paid to 34,000 households overcharged by 10 suppliers
Following a compliance review by Ofgem, ten energy suppliers including Octopus Energy, E.ON Next, EDF Energy, and OVO Energy were found to have overcharged customers with restricted meter infrastructure (more than one electricity meter) between January 2019 and September 2024. The suppliers were charging some customers more than is permitted under the price cap when multiple standing charges were combined with unit rates. Ofgem secured £5.6 million in refunds and £1.4 million in goodwill payments. Affected customers were refunded automatically. If you had multiple electricity meters during that period and have not received communication about a refund, contact your supplier to check whether your account was affected.
Source: Ofgem press release, March 2026. Last updated May 2026.
The most common energy billing errors and your rights
Overcharging above the Ofgem price cap
Energy suppliers cannot charge domestic customers above the Ofgem price cap on standard variable tariffs. If your unit rate or standing charge exceeds the current cap rates (electricity 24.67p/kWh, 57.21p/day; gas 5.74p/kWh, 29.09p/day for Q2 2026), check whether you are on a fixed deal at a different rate or whether there has been an error. Compare your bill against the current Ofgem rates.
Your right: Full refund of any amount charged above the permitted cap rate. Contact your supplier in writing with the specific dates and amounts. If unresolved, escalate to the Energy Ombudsman.
Surprise catch-up bills for old energy use
If your supplier has been issuing estimated bills based on inaccurate data and then sends a large catch-up bill, the Ofgem back-billing rule limits how far back they can charge. The rule applies when the billing failure was the supplier's fault, for example their system failed to process your meter readings.
Your right: Suppliers cannot charge for energy used more than 12 months before the corrected bill was issued if the delay was their fault. Any charges older than 12 months must be written off. This rule does not apply if you deliberately blocked meter access or acted unreasonably.
Bills based on inaccurate estimated usage
If your supplier has been issuing estimated bills that do not reflect your actual usage, you may have been significantly over or undercharged over time. Submitting regular meter readings prevents this. Smart meters send readings automatically, eliminating estimated bills entirely.
Your right: A corrected bill based on actual readings, and a refund of any overpayment. Provide meter readings to your supplier and request a corrected statement for the period in question.
Final bill not issued within six weeks of switching
When you switch energy supplier, your old supplier must issue a final bill within six weeks of the switch date. If they fail to do this, you are entitled to automatic compensation under Ofgem's Guaranteed Standards of Performance.
Your right: £30 compensation if the final bill is not issued within six weeks, and a further £30 if that compensation is not paid within 10 working days. Any credit on your old account must be refunded within 10 working days of the final bill.
How to resolve an energy billing error step by step
Gather your evidence
Collect your recent bills, meter readings, and any communications from your supplier. Note the specific dates the error covers, the amounts you believe are incorrect, and what Ofgem's current rate should be. Check your unit rate and standing charge against the current price cap rates.
Complain to your supplier in writing
Contact your supplier in writing by email or letter. State clearly what the error is, the dates and amounts affected, what resolution you are seeking (corrected bill, refund, or compensation), and the specific Ofgem rule or regulation that applies. Keep a copy of everything you send. Many suppliers resolve billing errors quickly at this stage.
Wait up to 8 weeks for a response
Energy suppliers have up to 8 weeks to investigate and respond to a formal complaint. If they resolve the issue within this time, the matter is closed. If you receive a deadlock letter or 8 weeks pass without resolution, you can escalate to the Energy Ombudsman.
Escalate to the Energy Ombudsman
The Energy Ombudsman is a free, independent service that can direct your supplier to issue an apology, correct your bill, and pay compensation. You can contact the Ombudsman at ombudsman-services.org after 8 weeks without resolution or upon receipt of a deadlock letter. The Ombudsman's decisions are binding on the supplier.
While you are checking your bill, check your tariff too
If your bill does not add up, you may also be overpaying on your tariff. Compare deals available for your postcode.
Questions people ask
Ofgem rules prevent energy suppliers from charging you for gas or electricity used more than 12 months ago if the billing failure was their fault. Any older charges must be written off. The rule does not apply if you deliberately prevented meter access or acted unreasonably.
For overcharging above the price cap you are entitled to a full refund. For a final bill not issued within 6 weeks of switching, £30 compensation applies, with a further £30 if that payment is not made within 10 working days. Additional compensation may apply if the error caused financial hardship.
Contact your supplier in writing, state the error clearly with dates and amounts, and specify the resolution you are seeking. If unresolved after 8 weeks or you receive a deadlock letter, escalate to the Energy Ombudsman at ombudsman-services.org. The service is free and the Ombudsman's decisions are binding on the supplier.
Not if the billing failure was the supplier's fault. Ofgem's back-billing rules prevent suppliers recovering charges for energy used more than 12 months before the corrected bill was issued when the delay was their error. Those older charges must be written off.
Related energy guides
Also worth checking: your tariff
If your bill does not add up, you may also be on an expensive tariff. Compare deals available for your postcode.
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