Backbilling Law Guide: What it is, your rights and FAQ


What’s in this guide?


With some customers receiving bills for thousands of pounds, a new light is highlighting the process of backbilling and whether there should be a change to the rules.

If you have experienced backbilling, this guide will tell you everything you need to know including what it is, the rules and what you should do.

Let’s dive in and find out more.

What is backbilling?

Back-billing is when your energy supplier doesn’t charge you enough for your energy, so they charge you for the x amount of months worth of energy you didn’t pay for correctly.

In other words, when your energy supplier doesn’t charge you enough for your monthly energy costs, you could end up being lumped with a massive, unexpected bill.

As these backbills can be up to any amount, Ofgem has imposed specific rules and regulations as to when they can charge you and to prevent backbilling that doesn’t follow the updated regulations.

What is the Law?

Thanks to Ofgem, customers will not be charged for the energy they used before 12 months before the supplier’s energy was noticed.

This means that your energy supplier can’t tell you that you haven’t been paying the right amount for five years, for example, giving you a ridiculous and unrealistic bill that could very well have been their fault.

However, this rule will not apply to those who have made it difficult or impossible for your energy supplier to charge you accurately.

For instance, if you have made it impossible for your supplier to be able to take a meter reading, the 12-month rule can’t protect you.

To avoid having to take responsibility, the best thing you can do is make sure that you are providing your supplier with regular meter readings.

What to do if your energy supplier is not following the rules

If your energy supplier isn’t following these rules as you feel they should, you must follow the complaints procedure outlined below.

Go Direct to your Supplier

Firstly, go directly to your energy supplier. You should make sure that you have your customer number and any relevant information to make your call go as smoothly as possible.

Depending on the circumstances, you should also try and have your meter number to hand too. You can find most of the information you need on your latest bill.

A simple complaint can usually be rectified on the phone; this is where you should write down the time, date, the person you are speaking to and vaguely what was said.

If you feel that your complaint is more complicated, you should follow up with a letter or email, so you have physical evidence of this conversation.

Write a Letter

The second step in lodging an effective complaint is to write a letter, this is if your energy supplier still can’t fix your problem.

You should make sure that you state at the beginning of this letter that you are writing to complain and ensure that you save a copy for yourself to use at a later date.

Include your case number, as well as bills, previous correspondence and anything else that supports your complaint.

When possible, send your post by recorded delivery as this means you can track your letter and make sure that your supplier received it.

Sending your post by recorded delivery helps combat potential delivery problems.

Get in touch with Citizens Advice

If your supplier still can’t resolve your problem, you can take your complaint to the Citizens Advice charity.

The first place you should look is the Citizens Advice ‘Adviceguide’, which was created to provide customers with information including what your rights are and what you should do next.

This helpful guide has different information in it depending on where you are in the UK, to make sure that you’re getting the right information for your area.

If you are elderly, unemployed or in a low-income household, Citizens Advice can handle your complaint about you as you would be part of the vulnerable group that they can help.

Unfortunately, if this doesn’t apply to you, they won’t be able to handle your complaint.

So what if you still can’t find the information or help you need?

The last step is to contact an Ombudsman.

Contact the Energy Ombudsman

If your supplier still can’t resolve your problem, the final option is to contact the Energy Ombudsman.

This is an organisation that can step in between you and your supplier and come to a resolution.

They are independent of energy suppliers and Ofgem, and are your advocate – this is why it is essential to keep all of that information before about the steps you had taken to get here.


Because the Ombudsman can take all of your evidence and approach the supplier with the weight of its authority to either get you an explanation, an apology or even in some instances financial compensation.


What is backbilling?

In short, it’s when you haven’t been paying enough for your energy and your supplier gives you a ‘catch up’ bill.

What if my supplier isn’t following the rules?

Check out the complaints procedure above.

Can I avoid backbilling?

Although you will not know when you will have backbilling as this will only occur when the supplier notices the error, there are ways that you can help ensure accurate billing:

  • Make sure that the meter serial number matches the one on the bill
  • Check estimate readings against actual readings from your meter
  • Check statements and raise questions to your supplier if there’s anything you’re unsure about

What if it isn’t my fault?

If the backbilling isn’t your fault, your supplier can’t charge you before 12 months before they notice the error.


Have you been wrongfully backbilled?

Do you want to learn more about your energy?

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