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Written by: EnergySwitch editorial team · Last reviewed: 9 October 2026
Direct answer: In credit: yes, you can switch at any time. Ofgem’s rules say your old supplier must send a final bill within six weeks and refund any credit within 10 working days of that bill. If it misses either deadline, you’re owed £40 compensation. In debt: it depends. On a credit meter (Direct Debit or pay-on-receipt), you can usually switch if the debt is less than 28 days old, and it’s added to your final bill. If it has been outstanding for 28 days or more after the supplier told you about it in writing, your supplier can block the switch until you pay. On a prepayment meter, you can switch with up to £500 of debt per fuel under the Debt Assignment Protocol. The debt moves to your new supplier, which has to agree to take it on.
Important: EnergySwitch is not the Energy Switch Guarantee. The Energy Switch Guarantee is a voluntary scheme run by Energy UK, the trade body for energy suppliers. EnergySwitch.co.uk isn’t a member of that scheme, isn’t affiliated with it and doesn’t run it. We explain the scheme below because people often confuse the two names.
Switching when you owe money: the 28-day rule (credit meters)
You’re on a “credit meter” if you pay for energy after you use it, by Direct Debit or when the bill arrives. According to Ofgem and Citizens Advice:
- You can switch if your supplier sent the unpaid bill less than 28 days ago, or hasn’t sent you a bill. Whatever you owe goes on your final bill from the old supplier.
- You can’t switch if the debt has been outstanding for more than 28 days. You’ll need to pay it first, or bring it down. If you apply anyway, Citizens Advice says the old supplier will probably reject the switch, and that can take a few days.
- Disputed bills: if you’ve complained that a bill is wrong and the supplier agrees there might be a problem, Citizens Advice says it should let you switch.
Ofgem’s rules say a supplier can only object on debt grounds if it has told you about the debt in writing and the amount has stayed unpaid for at least 28 days. If it blocks the switch, it must tell you why and how to resolve or dispute it. If you don’t agree, complain to the supplier. You can escalate unresolved complaints to the Energy Ombudsman.
What about Direct Debit arrears? These are treated the same way. The 28-day test runs from when the supplier asked you in writing to pay.
Switching on a prepayment meter with debt: the £500 Debt Assignment Protocol
Prepayment customers have a separate route, the Debt Assignment Protocol (DAP):
| Your prepayment debt | Can you switch? |
|---|---|
| Up to £500 per fuel (gas and electricity counted separately) | Yes, if the new supplier agrees to take the debt on. You then repay it to the new supplier. |
| More than £500 on either fuel | No. Reduce the debt first, then switch. |
Under Ofgem’s licence rules, suppliers must allow domestic prepayment customers with up to £500 of debt per fuel to transfer under the DAP. Citizens Advice says you’ll need to ask your new supplier to agree to transfer the debt along with your supply. It also has a template letter if your supplier won’t co-operate.
Switching doesn’t wipe the debt. It moves it. The benefit is that you can move to a tariff that may suit you better while you keep repaying. For the payment-method costs under this winter’s cap, see prepayment vs Direct Debit.
Switching when you’re in credit: getting your money back
Being in credit is common on Direct Debit. Citizens Advice explains that your monthly payment is an estimate, so you can end up paying more than you use. Switching is a natural point to get that money back.
Ofgem’s guaranteed standards after a switch:
| What your old supplier must do | Deadline | If it’s late |
|---|---|---|
| Send your final bill | Within 6 weeks of the switch | £40 compensation |
| Refund any credit balance | Within 10 working days of the final (or corrected final) bill | £40 compensation |
| Pay any compensation owed | Within 10 working days of identifying the breach | A further £40 |
To make sure your final bill is accurate:
- Give a meter reading on the switch date, or check that a smart meter sent one. Your new supplier will usually ask you for one.
- Don’t cancel your Direct Debit until the final bill has been settled. Your old supplier collects or refunds the balance.
- Check the final bill against your readings, and query any estimate.
- Prepayment credit: suppliers may refund it, or pass it on as credit to use with your new supplier. Ofgem treats that onward credit as a refund under the same 10-working-day standard.
Leaving credit in place over winter: if you’re not switching, Citizens Advice notes that some credit in summer and autumn helps cover higher winter bills. Think twice before asking for all of it back in October. You can still claim credit at any time, and your supplier must explain if it refuses.
What is the Energy Switch Guarantee? (And why it isn’t us)
The Energy Switch Guarantee (ESG) is a voluntary commitment by some energy suppliers. It’s run by Energy UK. Again, EnergySwitch.co.uk is a separate, independent website. We aren’t Energy UK, we aren’t a signatory, and we aren’t connected to the scheme.
According to Energy UK, suppliers that sign up commit that:
- a switch to a new tariff or supplier can happen within five working days
- the supplier you’re moving to handles the transfer
- if you change your mind within 14 days, you stay with your existing supplier or tariff
- any credit due is refunded within 14 days of your final bill
Energy UK also measures signatories against targets. These include 98% of supplier switches completed within five working days, 90% of final bills issued within six weeks, and 90% of credit refunds issued within 10 working days of the final statement.
When we checked, Energy UK listed these signatories: British Gas, E.ON Next, Ecotricity, EDF, Fuse Energy, Octopus Energy, Outfox the Market, OVO, ScottishPower, So Energy and 100Green. Energy UK says not all suppliers are members. The ESG adds to the legal standards. It doesn’t replace them: Ofgem’s six-week and 10-working-day rules apply to all suppliers.
If you have a problem with a switch covered by the ESG, Energy UK says to contact your new supplier first. If that doesn’t resolve it, go to the Energy Ombudsman. Energy UK doesn’t handle individual complaints, and neither do we.
If you’re behind on your energy bills
If you can’t switch because of debt, or you’re worried about falling behind:
- Contact your supplier early. Ofgem says suppliers must help if you tell them you can’t pay, for example with an affordable repayment plan or emergency credit.
- Check what help you can get. The Warm Home Discount (£150 for eligible households this winter) and other schemes are covered in our Warm Home Discount 2026/27 guide.
- Read our step-by-step guide to what to do if you get behind on your energy bills.
- Free advice: Citizens Advice can help with energy debt.
For context on prices: Ofgem’s typical Direct Debit dual-fuel level for 1 October to 31 December 2026 is £1,723 a year, and its typical prepayment level is about £1,678. These are typical-usage illustrations, not your bill. The January to March 2027 cap is due by 25 November 2026 and hasn’t been announced yet. See the energy price cap hub.
When you’re ready, compare tariffs with your own usage on compare gas and electricity, and follow how to switch energy supplier. Exit fees can apply if you leave a fixed tariff early. Ofgem’s rules say they can’t be charged in the last 49 days of a fixed term.
FAQs: switching in debt or in credit
Can I switch energy supplier if I owe money?
On a credit meter, usually yes if the debt is less than 28 days old. It goes on your final bill. If it’s been outstanding for 28 days or more after the supplier told you in writing, the supplier can block the switch until you pay. On prepayment, you can switch with up to £500 of debt per fuel if the new supplier agrees to take it on.
What happens to my credit when I switch energy supplier?
Your old supplier must send a final bill within six weeks and refund any credit within 10 working days of that bill. If it misses either deadline, Ofgem’s guaranteed standards say you’re owed £40.
Can I switch supplier with a prepayment meter and debt?
Yes, if you owe up to £500 for gas and up to £500 for electricity. The debt transfers to the new supplier under the Debt Assignment Protocol, as long as it agrees. Above £500 on either fuel, you’ll need to reduce the debt first.
Is EnergySwitch the same as the Energy Switch Guarantee?
No. The Energy Switch Guarantee is Energy UK’s voluntary scheme for signatory energy suppliers. EnergySwitch.co.uk is an independent comparison and information website. It isn’t a member of the scheme and isn’t affiliated with Energy UK.
What does the Energy Switch Guarantee promise about credit refunds?
Energy UK says signatories commit to refunding any credit due within 14 days of your final bill. It also tracks a target of 90% of refunds within 10 working days of the final statement. Ofgem’s legal 10-working-day standard applies to every supplier.
Can my supplier stop me switching?
Only in limited cases. The most common is debt that’s been outstanding for 28 days or more after you were told about it in writing. The supplier must tell you why it objected and how to resolve or dispute it. If you disagree, complain, and use the Energy Ombudsman if needed.
Sources
- Ofgem: Switch your home energy supplier (28-day debt rule, £500 prepayment debt)
- Ofgem: Licence guide, switching (Debt Assignment Protocol £500 per fuel; 49-day exit fee rule)
- Ofgem: Decision on review of domestic debt objections (written notice and 28 days)
- Ofgem: Are you owed money on your energy bill? (six-week final bill, 10-working-day refund, £40)
- Citizens Advice: Switching if you owe your energy supplier money
- Citizens Advice: Claim back credit from your energy supplier
- Energy UK: Energy Switch Guarantee (commitments, KPIs, signatories)
- Ofgem: Changes to energy price cap between 1 October and 31 December 2026
Last reviewed: 9 October 2026. Written for Great Britain households. EnergySwitch.co.uk is independent. It isn’t the Energy Switch Guarantee, isn’t affiliated with Energy UK and isn’t Ofgem Confidence Code accredited.
