How to Complain About Your Energy Bill UK 2026 | BillFight

If your energy bill is wrong, the worst move is to ignore it and keep paying. Many UK households overpay because they do not know what regulations protect them or how to write an effective complaint. This guide explains how to check your bill, what to include in a complaint, and how to escalate if your supplier ignores you.

Step 1: Check your bill against reality

Compare the meter readings on your bill with your actual meter or smart meter readings. Look at the tariff rates being applied. Check whether the bill is estimated or based on actual readings. If anything looks wrong, you have grounds to complain.

Step 2: Understand what protects you

Ofgem supplier licence conditions require your energy company to bill you accurately (SLC 7), treat you fairly (SLC 25), and follow back-billing rules. The Consumer Rights Act 2015 gives you additional protections around service quality and pricing.

Step 3: Write a formal complaint

A formal complaint should cite the specific regulations your supplier has breached, describe the issue clearly, state what resolution you want, and mention your right to escalate to the Energy Ombudsman after 8 weeks.

Step 4: Know the escalation route

If your supplier does not resolve your complaint within 8 weeks, or issues a deadlock letter, you can escalate to the Energy Ombudsman for free. The Ombudsman can order refunds, compensation, and corrective action. Their decision is binding on the supplier.

Common mistakes to avoid

Paying an incorrect bill without challenging it first
Sending an emotional complaint without citing regulations
Not keeping copies of bills, readings and correspondence
Waiting too long to escalate to the Ombudsman

When to use a formal complaint letter

If the disputed amount is significant, your supplier is being unhelpful, or you want the strongest possible case for Ombudsman escalation, a formal complaint letter citing the exact regulations is the right approach. BillFight generates this for £4.99.