How can you tell if your energy bill is wrong?

Do mistakes with energy bills happen? Sadly, yes – and customers often don’t know for sure if the bill is wrong or how to challenge it.

In 2021, the energy regulator Ofgem announced that around 1 million people had been overcharged an estimated £7.2 million by 18 energy firms. And that was just as a result of switching suppliers. In 2024, even more things are going wrong across the energy sector.

Energy bills can be complicated – and how they are calculated isn’t particularly easy to understand. Energy firms often automate the process of calculating bills – which means you only get an actual human being checking the calculation if you complain. Add estimated readings, faulty meters, different energy tariffs and human errors into the mix and you can see why the bill you receive may be inaccurate.

In recent months we’ve seen an explosion of complaints about incorrect energy bills as people receive demands for payments that are clearly wrong. So what’s going on? Here’s our Resolver guide to your rights if you are overcharged.

What causes billing errors?

There are three main reasons for the big growth in billing disputes:

These days many bills are estimated using new IT systems, or old and faulty meters, which can lead to all kinds of errors.
Millions of people have switched to new providers, carrying over all the old problems with their bills to a new energy firm, making it harder to figure out what’s gone wrong.
The huge increase in energy bills means that it’s much harder for people to know if their bill is wrong or just increasing in line with the energy price cap.

How do I know if there’s been an error with my bill?

You may not be able to become an energy expert overnight but you can trust your gut. Your energy bill should not have exceeded the energy price cap or gone up more than 59% in most cases – so if it has, you could make a complaint.

(Between 1 January to 31 March 2024 the energy price cap is set at £1,928 a year for a typical household who use gas and electricity and pay by Direct Debit.)

Some people on ‘variable’ tariffs have reported big increases in their direct debits. Ofgem has now said that if these payments increased by 100% or more they should be investigated by the energy firms. While underestimated bills can lead to price hikes later on, energy firms should not be sneaking in big price rises over the current price cap. If this has happened to you, don’t wait – make a complaint now.

If you’re on a standard tariff and have been hit with a price rise that increases your bill over the 54% you should ask the firm to explain in writing why it has done this and what other options were available to you.

Have a look on your bill under the ‘energy usage’ section. This will show if your supplier has been relying on estimated readings. Even if the firm was underestimating by a small amount, this can add up dramatically over the years. The business should not just pass on estimate errors to you in increased bills – they have an obligation to get things right too.

Take a common-sense view. If your bill was £800 a year and now it’s £3000, then clearly something is amiss. That’s way over the price cap and though there are lots of reasons why this might be, you should be asking the energy firm to explain what’s going on in straightforward terms.

So what can I do?

If you are trying to do your own investigation in to your bill, the first thing to do is take a proper meter reading from both gas and energy meters (if you have dual fuel). You can then sense check the readings with your bill.

If you’ve got an old analogue meter (with dials like clock faces that go in different directions) it’s easy to make a mistake so don’t rush. If your smart meter display is playing up or not transmitting, then report that too. Make sure you photo the meters so you have another record of the reading.

If you think your meter is faulty, your energy provider may ask you to take daily meter readings for seven days to see if there’s an obvious problem. They should send out engineers to assess the meter’s performance or even do a forensic analysis of your bills.

Energy firms should not be ‘back billing’ you for longer than 12 months from the date on the bill. Back billing is when a firm charges you for energy that you used over 12 months previously – but didn’t bill you for it correctly at the time. Find out more about back billing rules here.

How do I make a complaint?

Resolver can help you make a complaint for free about anything energy related, from incorrect billing to switching errors. Get started here: https://www.resolver.co.uk/

There is a free Energy Ombudsman too if you still aren’t happy. Resolver will automatically refer you to them if your complaint isn’t sorted out.

You can also use Resolver to save money, switch to a better insurer and find all our money saving guides too. www.resolver.co.uk