British Gas bill for £900 and saying I used 3000kwh in 1.5 months!

[RumHam]

We were switched to British Gas a couple of years ago after our old electric company went bust. We usually pay around £200 odd every quarter for our electric. We just got a bill through for £900 which has used up my £600 credit and left me in -£300 arrears.

I will include the numbers for the last few bills for context. They are saying our use has jumped from around 500kwh to 3595! It's impossible we have used approximately half a year's worth of energy in that time! None of our energy habits have changed and we have no new appliances. The only change is that we have been moved to the new BG billing system. We were moved in Sept 2024 and apparently we started to use £150 worth of electricity in one week on September 22nd. Then the rest was from 1st Oct to 14th Nov.

Here are the numbers

29th Nov 2022 - 25th March 2023
kWh = 600
Cost = £297.33

26th March - 23rd June 2023
kWh = 395
Cost = £192.61

24th June - 23rd Sept 2023
kWh = 376
Cost = £173.26

24th Sept - 23rd Dec 2023
kWh = 530
Cost = £203.74

24th Dec 2023 - 23rd March 2024
kWh = 546
Cost = 213.50

24th March 2024 - 23rd June 2024
kWh = 426
Cost = £164.60

23rd June - 21st Sept 2024
kWh = 364
Cost = £140.05

22nd Sept - 14th Nov 2024
kWh = 3595
Cost = £887.17

Meter reading
Sept 2024 - 0018313
Nov 2024 - 0021343
Now Dec 2024 - 0024785

My smart meter and the BG website say we are using around 13kwh a day and spending £3-5 on electric which seems right. Where did 3595 come from?! We've contacted BG. One caller said it was definitely an error and will be fixed within a week and another said they can't be sure if it's an error and we've to keep taking readings and call them back in a week and they'll get an engineer to check the meter but it's very rarely a faulty meter apparently. We asked if it could have anything to do with the switch over to the new billing system as we've heard some stories but they said it's doubtful.

I'm worried sick. I can't sleep or eat over worrying about this. I've never had this kind of problem before.Thank you in advance for any advice you can offer.

How large is your house? New? Well insulated? How warm do you keep your home?

In winter my heating usage goes up by a factor of 13. My usage jumped from 55kwh for heating/water heating in August to 730kwh in November, and I am as frugal as I can be. In a very cold January I can use 2,000 KwH .

But 3,000 kwH seems high and we haven't had much cold weather yet.

Smart meters are horribly unreliable so check the main meter manually.

According to British gas, the average 3 bed house annual utility bill with 2 or three people is £1,800 a year.

To mid-Nov, your annual bill according to their numbers, is £1,400 so not unusual.

£200 every quarter is low

We are two adults, no kids. We have a one bedroom flat - top floor in a 4 in a block flat. I'm not 100% on when the flat was built, I think between 1930-50s.

We don't have the heating on often and even when we've had it on for almost a week straight when one of us has the flu, our readings never went as high as 3000+. I mainly use my heat pad for warmth rather than the actual heating unless it gets really cold. Been using my heat pads for years so they aren't anything new that's been added to the energy use.

Our main usage will come from tech and especially the TV and hubby's PC equipment. Had all these appliances for years both in our current flat which we've been in for 5 years and ij the old flat and we always had quarterly bills ranging from £190-300ish

Are all the numbers on the bills correct reading or are any estimated?

Does the latest reading (and any others that you have records for) match what it says on the meter?

You haven't accidentally left an immersion heater or other heating appliance switched on have you?

We were in a very similar situation. Our provider went bust, we were advised we would be transfered to X company on the mist like for like basis possible. Turns out the 'most like for like' they could offer were horrendous rates (funny that !) Fortunately we had credit which took the blow but it was about 700 odd pounds we could have had if I had not been so naive amd the company we not con artists

Are you able to give some of the meter readings for the previous periods @RumHam

When were you switched to the new billing system, did it seemingly go wrong after that. After we were switched we had no proper electric bill for a year, smart meter was sending readings as I could see daily amounts but we had no readings registered so we're only charged for standing charge, it took a year to get a correct bill, obviously we weren't overpaying so it wasn't so urgent. It seemed to be a case of computer said no with us.

With gas there is a conversion calculation to get kWh, have you checked they are not suddenly using the wrong one, it's cubic feet or metres but one could be 3 times more than the other if wrong or maybe 9 times?? Anyway a lot of difference

As you are in a flat any chance you are being charged for more than one flat?

Ignore me, I just see you were electric

We are in dispute with British Gas about this. They moved us from their old system to their new system and tried to charge us £1600. I have fought and fought and finally they have admitted they are wrong.

Put in a complaint, and document everything. (I have a folder where I print out everything and wrote the dates I contact them). Just hunker down and fight through them telling you they can't do anything. They can. This is happening to alot of people when British Gas move them to the new system.

Mine was because they used estimated readings. I left and went to Octopus 2 months later, who have been brilliant. The final reading on the old billing system was higher (by more than £600) than my final reading that was taken by both me and Octopus. BG are arseholes!

What date did you move to the new system, ours went wrong straight after we had moved

What is your price per unit and has it changed?
Have you read the actual meter and checked it matches the smart reading?
I can't quite work out from your figures, does the bill they have sent match the units you think you have used?
I mean- stop looking at the £ amount and check the unit usage and see if that matches your meter.

My sympathies, electric companies and their billing are godawful. fyi, Do not touch EON with a 20 ft pole, they are criminally incompetent. I spent MONTHS arguing a 3k (business, high use) bill with them when we moved our accounts, their billing system was so incredibly chaotic that I won eventually but it was so stressful.

We are in the same situation as @SparklyCyanNewt - since they swapped over to their new system they’ve tried to over charge us. Every time my husband calls up to try and sort it out they have a completey different amount for us to supposedly pay.

You need to follow complaints procedure-
From memory: write them a formal letter stating clearly that you are disputing the bill. Then they HAVE to regard it as in dispute and can't chase you for the payment and have a certain number if days to respond.
We sent it recorded delivery by post as well as email as kept getting given the run around on
Make sure you keep a copy.
You csn go to the ombudsman if you don't get anywhere (not difficult, just time consuming) but you have to have gone through the complaints procedure snd given them the correct time to respond first.
Their complaints procedure is on their website and is something they have to follow, make sure you follow the procedure correctly so they can't wiggle out of it.
www.britishgas.co.uk/complaints.html

I'm with British gas lite as a business, what is the new system you mean? Im wondering if i need to watch out for something changing!
We have been on monthly payments (month in arrears, from a reading) since we joined nearly 2 years ago. After the chaos of our previous company and the completely impossible to understand, quarterly estimated billing thing that we always used to have (where you pay a DD based on est use and if you use different it gets evened out later) it is so simple. We use it, they invoice us and then we pay it. Much less room for error.

Also with British gas and been fobbed off constantly about meter issues when switching to their new system. Definitely make a formal complaint and if you get no traction write to some on the money columns in the newspaper, they tend to sort these things quickly.

@Onlyvisiting im not 100% sure as DH is dealing with it but British Gas moved over to a new system (I’m assuming it’s a billing system or something) and tried to tell us we owed a huge amount of money… then every time DH has called them, they come up with completely different figures. So basically they have no idea !

It might be worth looking at the Energy forum on MoneySavingExpert and posting on there with your readings to see if anyone can help, it's quite a large forum.

I had very similar last autumn with British Gas - a random very high bill that wasn't in line with my usual useage.

They did concede it was an error after a few days of me chasing them. I also put in a complaint about the process - the stress it had caused, that it was only my own vigilance that stopped them taking money we didn't owe etc.
They couldn't have cared less.

We left immediately afterwards - switched to Octopus using a code from a friend so we both got a bonus bit of credit on our accounts.

I had big problems with BG. Then Scottish power, same thing as you, but with the old type meter, not a smart meter, kept being told a different story every time I rang.. changed to extra,they went bust put back to Scottish power. It took them 9 months to sort out the problem, during which time they craftily froze the account so I couldn't swap supplies. It took them 4 months to give me an account number, course when you ring "please say or key in your account number". I went with octopus because they were shown to have the best customer service. That was ok till last summer,our electricity charges weren't showing on the bill, they were showing on the usage,4 months of phoning, again different story every time we rang.. we're pensioners,we couldn't afford to get into debt with them especially with the winter bills coming up.

@Onlyvisiting it's a whole new billing system that BG have been migrating customers to over the last 2 or 3 years, 7.5 million of them apparently, not sure if it's just domestic customers but they will email you and let you know as you get a new account number and can't access your online account properly for a couple of weeks, there will be a link to the old platform.

Hmm. Thanks, as we have been with them less than 2 years I wonder if we are already on it? It's certainly different to the quarterly bills we have had with all previous suppliers.
We had a smart meter fitted about a year ago too. Mostly working OK although it took about 10 months for their system to stop asking us fir meter readings despite having a reading logged on the the account.
My main tip for anyone these days is don't trust them to correctly administer anything. Keep an eye on your meter usage and keep good records. Every bill and every reading and every email and check invoices match the readings.
You probably won't need it but when they do cock up it will be so much easier to sort out than blindly assuming they are remotely competent or have any integrity.

OP, a one bed flat, with accommodation below (heat rises). Unless your roof is completely unlined and uninsulated, I'd say that is definitely wrong.

It sounds like heating for all four flats. I'd get an independent electrician to check the meter and wiring.