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SteveBerning
Rank 2
June 11, 2025
Solved

Underestimated usage - does this fall under Ofgem's back-billing rules?

  • June 11, 2025
  • 20 replies
  • 1020 views

I today noticed a big difference between an email that said I had a £1,169.70 credit and my App account now saying I owed £513.27. i don’t get the estimate issue as have a smart meter, that is what they are for, no?

But here’s the kicker, I now have an email today (11/6) saying why. The email says they are not allowed to go back more than a year and they calculate they charged me £2,746.40 instead of £4,059.32 (£1312.92 undercharged). it seems because I was overpaying (and took a credit of £1,000 on 26th June 2024) my balance was £3,982.55 in said period so they would credit me the £76.77 shortfall only.

Surely penalising someone for having too much credit is against the spirit of Ofgem’s rules.

I have budgeted a certain amount of money and suddenly i am being charged an extra £1,236.15 (45%) for a period that expired over a year ago. 

If I had merely paid the minimum amounts or taken that £1,000 16 day earlier then I would be £1,000 better off. That’s got to be wrong

Best answer by Emmanuelle_OVO

Updated on 29/08/25 by Emmanuelle_OVO:

Hey ​@SteveBerning,

I’m sorry for the issues you’re having,

OVO Energy, like other energy suppliers, may send back bills (also known as "catch-up" bills) to customers when they haven't been charged correctly for energy use. This can happen due to various reasons, such as inaccurate billing, errors in meter readings, or issues with how the supplier accesses meter information. However, back billing rules, set by Ofgem, protect consumers from being charged for energy used more than 12 months ago if certain conditions are met. My advice would be to check your previous meter readings to see if there was a period with no meter readings. You shouldn’t have been issued a refund for such a large amount without being required to submit at up to date meter reading, so it seems that an error may have been made on our side.

Understanding Back Billing:

  • What it is:

    Back billing is when an energy supplier sends a bill for energy used in the past, often due to past errors or undercharging. 

  • Why it happens:

    Common reasons include estimated meter readings being too low, incorrect meter readings or addressing errors, or delayed billing due to technical issues. 

Back Billing Rules:

  • Ofgem rules protect customers from being charged for energy used more than 12 months ago if:
    • They haven't received an accurate bill for that period. 
    • They haven't been informed about charges via a statement of account. 
    • Their direct debit was previously set too low to cover the charges. 
  • These rules don't apply if the supplier sent a bill within the 12-month period and the customer didn't pay it. 

What to do if you receive a back bill:

  1. 1. Check the bill carefully:

    Ensure it's accurate and that the charges are for energy you actually used. 

  2. 2. Verify the 12-month rule:

    See if the charges are for energy used more than 12 months ago and if the above conditions apply. 

  3. 3. Contact OVO:

    If you have any concerns or questions about the back bill, contact OVO Energy's customer service to discuss the situation. 

  4. 4. Consider escalating the complaint:

    If you are unable to resolve the issue with OVO, you can escalate your complaint to the Energy Ombudsman. 

  5. 5. Seek advice:

    If you need further assistance, you can contact Citizens Advice or MoneySavingExpert for guidance

 


Hope this helps.

20 replies

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S
Rank 2
SteveBerningAuthor
Rank 2
June 18, 2025

Thanks, sounds like you’ve been through it and at the risk of sounding like an idiot I am not sure I have got the energy to fight this. It definitely feels at odds with Ofgems letter on the consultation because it’s meant to prevent consumers getting shocks for reasons that are not their fault.

Emmanuelle_OVO
Retired Moderator
Emmanuelle_OVOSolved
Retired Moderator
June 19, 2025

Updated on 29/08/25 by Emmanuelle_OVO:

Hey ​@SteveBerning,

I’m sorry for the issues you’re having,

OVO Energy, like other energy suppliers, may send back bills (also known as "catch-up" bills) to customers when they haven't been charged correctly for energy use. This can happen due to various reasons, such as inaccurate billing, errors in meter readings, or issues with how the supplier accesses meter information. However, back billing rules, set by Ofgem, protect consumers from being charged for energy used more than 12 months ago if certain conditions are met. My advice would be to check your previous meter readings to see if there was a period with no meter readings. You shouldn’t have been issued a refund for such a large amount without being required to submit at up to date meter reading, so it seems that an error may have been made on our side.

Understanding Back Billing:

  • What it is:

    Back billing is when an energy supplier sends a bill for energy used in the past, often due to past errors or undercharging. 

  • Why it happens:

    Common reasons include estimated meter readings being too low, incorrect meter readings or addressing errors, or delayed billing due to technical issues. 

Back Billing Rules:

  • Ofgem rules protect customers from being charged for energy used more than 12 months ago if:
    • They haven't received an accurate bill for that period. 
    • They haven't been informed about charges via a statement of account. 
    • Their direct debit was previously set too low to cover the charges. 
  • These rules don't apply if the supplier sent a bill within the 12-month period and the customer didn't pay it. 

What to do if you receive a back bill:

  1. 1. Check the bill carefully:

    Ensure it's accurate and that the charges are for energy you actually used. 

  2. 2. Verify the 12-month rule:

    See if the charges are for energy used more than 12 months ago and if the above conditions apply. 

  3. 3. Contact OVO:

    If you have any concerns or questions about the back bill, contact OVO Energy's customer service to discuss the situation. 

  4. 4. Consider escalating the complaint:

    If you are unable to resolve the issue with OVO, you can escalate your complaint to the Energy Ombudsman. 

  5. 5. Seek advice:

    If you need further assistance, you can contact Citizens Advice or MoneySavingExpert for guidance

 


Hope this helps.

Renewable Energy? Big Fan.
S
Rank 2
SteveBerningAuthor
Rank 2
June 19, 2025

Thank you, I will check past bills and correspondence. As mentioned I have been on a smart meter so it seems a little strange to me,

    Emmanuelle_OVO
    Retired Moderator
    Emmanuelle_OVO
    Retired Moderator
    June 20, 2025

    Hey ​@SteveBerning,

     

    Keep us posted with how this progresses. This topic may also help:
     

     

    Renewable Energy? Big Fan.
    S
    Rank 2
    SteveBerningAuthor
    Rank 2
    June 25, 2025

    I have now had an opportunity to do a bit more research.

    It seems that for a period from around June 23 there was no usage charges at all on my electric bill, just the standing charge so only around £15 per month was charged. So not even any estimated usage. It’s hard to know what usage costs would be (£80 monthly?) but given the majority of my bill was gas and there was so much volatility around prices I didn’t pay much attention as was paying c. £400 per month on direct debit at one stage.

    However having built up a substantial credit, I did try to take a refund in June 24 but was prevented because it said I must submit meter readings. 

    Of the criteria mentioned above, the fact I was in credit suggests my direct debit was not previously set too low to cover the charges so struggling to see how backbilling rules dom’t apply. 

    I wrote to Ovo in June 24, so well within the back-billing tolerance level and said I am trying to take a refund but it won’t let me until I submit meter readings but I can’t because I am on a smart meter.

    The member of the Ovo team did speak to me at that time and refunded £1,000  when it should have been obvious to them there was a problem.

    I come back to the back billing principles that place responsibility on the energy companies to spot problems much earlier rather than it emerge 2 years later - a week or so before I am about to move house.

    I have raised a complaint so will see how it progresses.

     

     

     

     

     

      Firedog
      Super User
      FiredogSuper User
      Super User
      June 26, 2025

      … my direct debit was not previously set too low to cover the charges so struggling to see how backbilling rules dom’t apply. 
        

      I think you’re misinterpreting this criterion:

      You cannot be charged for energy used more than 12 months ago if:

      • your Direct Debit amount was previously set too low to cover any charges due

      Because your DD wasn’t set too low, you can be charged.

       

      Noel | I have no official status; I'm just a volunteer who comes here to help other customers. My gear: Aclara SGM 1416-B Electricity-only E7 meter; Chameleon IHD3-PPMID-AAA | It may look as if I know what I’m talking about, but don’t let that fool you. |
      S
      Rank 2
      SteveBerningAuthor
      Rank 2
      June 26, 2025

      Thanks. 


      Agree I have it the wrong way round. 

      So it’s saying if you set your DD at an originally realistic/high level and you end up with a big credit due to an error,  the supplier can go back and take what was paid to the account.
       

      It does seem very arbitrary, can be under by a few pounds and rules apply but over and don’t. Also still seems wrong that what you are able to afford can dictate it. Fact is OVO should have spotted the problem when I asked for the credit.

       

      the Ofgem open letter in 2017 was targeting the situation I am in, a £1400 swing on my account for usage over a year ago.

       

        C
        Rank 6
        chrisablake
        Rank 6
        July 4, 2025

        Can you keep us updated I’d be interested how this gets resolved. I was unaware of “Back Billing” rule. Learn something new everyday. 
        Good Luck 

        Wibbly Wobbly Hypermobile - EDS’er
          C
          Newcomer
          callamart
          Newcomer
          November 20, 2025

          Important: we’ve underestimated your energy use

          I have just received one of these messages too.  I am most concerned that it refers back to 2023 when for most of the year we were undergoing major renovations and had to move out so we used hardly any energy.  I telephoned and after holding for around 15 minutes managed to confirm that the message was automatically generated by the system and nothing checked before it was sent.  I am now awaiting a comprehensive explanation!

          Ben_OVO
          Community Manager
          Ben_OVO
          Community Manager
          November 21, 2025

          Morning ​@callamart and welcome to the OVO Forum.

           

          Has your balance been adjusted yet? I’d recommend seeing if you have any previous readings from that time, and sending them in if so. 

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