How to check a bill for mistakes

The most common billing errors

1. Estimated readings that are too high or too low

If the bill shows “E” or “estimated”, the company guessed. Read your meter and compare. A high estimate means you are overpaying now. A low one can mean a large catch-up bill later.

2. Being charged twice

Look for the same charge, date or amount appearing twice, or billing periods that overlap with your last bill.

3. Paying a higher price after a deal ended

When a fixed deal or contract ends, prices often go up. Check the contract or tariff end date on the bill.

4. Charges after you cancelled or moved out

If you closed the account or moved home, you shouldn't be billed for later dates. Keep the confirmation you got when you cancelled.

5. Fees you were never told about

Late-payment, paper-bill, admin or “service” fees. Ask where in your contract the fee is set out.

6. A missing payment

Compare the “payments received” line with your bank statement.

7. Old charges suddenly appearing (back-billing)

A catch-up bill for energy you used a long time ago. In Great Britain, Ofgem's back-billing rules mean energy suppliers generally can't bill you for energy used more than 12 months before, if you weren't billed correctly and it wasn't your fault.

8. Maths that doesn't add up

Multiply units by the unit rate, and days by the daily charge, then add tax. Worked example: how to read a bill.

A simple 10-minute routine

1. Put this bill next to your last one and your bank statement.
2. Check the dates, readings and payments line by line.
3. Circle anything you don't understand or recognise.
4. Ask the company to explain each circled item, ideally in writing, by email or webchat, so you have a record.
5. If the answer doesn't make sense, you can complain. See how to complain about a bill.