Complaints · UK · Energy (gas and electricity)
How to complain about an energy company (UK)
Complain to your energy supplier in writing first. It has 8 weeks to sort it out; if it sends a deadlock letter sooner, you can escalate at once. Then take it to the Energy Ombudsman, which is free, within 12 months of the deadlock letter. Ofgem regulates suppliers but does not investigate individual disputes. Rules checked 27 September 2026.
Complaint routes and time limits checked against official sources on .
First
Complain to the supplier
in writing
Wait
8 weeks
or a final response
Then
Energy Ombudsman
free
Checked
27 Sep 2026
official sources
1. Complain to the supplier first
Make a formal complaint to your supplier in writing (email, web form or letter) and say clearly that it is a complaint. Ask for a reference number and keep it. Include: your account number and supply address; what went wrong and when it started; meter readings with dates, and the bills you dispute; what you want: a corrected bill, a refund, a credit or an apology; a request for a deadlock letter if they can't fix it.
2. How long to wait
Your supplier has 8 weeks to resolve the complaint. If it sends a deadlock letter sooner, you can escalate straight away.
3. Escalate to Energy Ombudsman
Within 12 months of the deadlock letter. It is free. It can: practical action such as crediting your account or changing a tariff; an apology; a financial award for time and trouble (the most common award is around £50); the supplier must carry out an accepted decision within 28 days. energyombudsman.org
Who does not handle your complaint
Ofgem regulates energy suppliers but does not investigate individual disputes. The Energy Ombudsman does.
Where to escalate and the time limits
Time limits run from the date shown in each row. Keep the final response or deadlock letter, because the ombudsman will ask for it.
| Who | Time limit | Cost |
|---|---|---|
| Energy Ombudsman | Within 12 months of the deadlock letter. | Free |
Evidence to keep
Bills and statements for the disputed period. Dated meter readings and photos of the meter. Emails, letters and chat transcripts. Notes of phone calls: date, time, name and what was said. The deadlock letter or 8-week letter.
Also worth knowing
Citizens Advice can refer difficult or urgent cases, or vulnerable customers, to its Extra Help Unit.
Guides and definitions
- Section 75 or chargeback: which should you use to get your money back? (Guide)
- Chargeback (A chargeback asks your card provider to reverse a debit or credit card payment under Visa, Mastercard or American Express rules, usually within about 120 days.)
- Ombudsman (An ombudsman is a free, independent body that settles complaints against companies or public bodies once the organisation has had its chance to put things right.)
- Section 75 (Section 75 of the Consumer Credit Act 1974 makes your credit card provider jointly liable with the seller for a single item costing over £100 and up to £30,000.)
- Deadlock letter (A deadlock letter is a company's written final answer to your complaint, which lets you go straight to the ombudsman instead of waiting the usual 8 weeks.)
Complaints about something else
- Broadband, landline and pay TV (UK)
- Mobile phone (UK)
- Bank, credit card or loan (UK)
- Insurance (UK)
- Pensions (UK)
- Investments or financial advice (UK)
- Flights and airlines (UK)
- Trains (UK)
- Parcels and post (UK)
- Online shopping or a shop (UK)
- Council services (UK)
- Housing association or council housing (UK)
- Private landlord or letting agent (England) (UK)
- NHS in England (UK)
- Water (England and Wales) (UK)
All complaint guides · Get your route with dates and a letter
Common questions
How long does an energy supplier have to deal with a complaint?
8 weeks. If you complained on 1 September 2026, you can go to the Energy Ombudsman from 27 October 2026. If the supplier sends a deadlock letter saying it can do no more before then, you can go to the Ombudsman straight away.
Can Ofgem deal with my complaint about my energy supplier?
No. Ofgem says it does not get involved with individual complaints about suppliers or investigate individual disputes. The Energy Ombudsman handles unresolved complaints for free. Citizens Advice can refer urgent or difficult cases, and vulnerable customers, to its Extra Help Unit.
How long do I have to go to the Energy Ombudsman?
12 months from the deadlock letter. A deadlock letter dated 15 September 2026 gives you until 15 September 2027. Missing that date means the Ombudsman is likely to refuse the case, so escalate as soon as the supplier stops helping.
What can the Energy Ombudsman make my supplier do?
It can tell the supplier to take practical action such as crediting your account or changing your tariff, apologise, or pay a financial award for time and trouble. The most common award is around £50. Once you accept a decision, the supplier must carry it out within 28 days.
What evidence do I need for an energy complaint?
Keep bills for the disputed period, dated meter readings and photos of the meter, emails and chat transcripts, and notes of every call with the date, time and name. The deadlock letter or 8-week letter is the key document the Ombudsman asks for.
Sources and assumptions
- General routes from official sources; a scheme may ask for more before it takes your case.
- Ofgem: Complain about your energy supplier or network operator
- Energy Ombudsman: Energy Ombudsman FAQs
Guidance on where to complain, not legal advice.