What is a deadlock letter, and how do you get one?

Great Britain · Rules checked 24 October 2026 · Not legal advice

Free tool: Energy Ombudsman date checker. Enter your complaint date to see when you can escalate.

A deadlock letter (or final response) is a letter or email from your supplier saying it can't do anything more to resolve your complaint. It must tell you that you can go to the Energy Ombudsman, and give its details.

Why it matters

Normally you wait 8 weeks after complaining before the Ombudsman will take your case. A deadlock letter lets you go straight away. You then have 12 months from the letter to escalate.

What the law requires

Under regulation 6 of the Gas and Electricity (Consumer Complaints Handling Standards) Regulations 2008, a supplier must send you written notice of your right to go to the Ombudsman on the earlier of: the first working day after it realises it can't resolve the complaint to your satisfaction, or the end of the Ombudsman's waiting period (8 weeks). The notice must say the scheme is free and independent and that its decision binds the supplier but not you.

How to ask

Write: "If you can't resolve this, please send me a final response (deadlock letter) now." Letter 07 in the kit includes this. Use the date checker to track your deadlines.