Gas bills are the hardest to check because your meter measures volume, not kWh. Upload your bill and we'll do the conversion and the maths for you, free.
Checked 7 October 2026Written by the MyBillChecker team
Why gas bills go wrong
Your meter counts cubic metres (or hundreds of cubic feet on older meters). Your supplier converts that to kWh using a set formula. A wrong meter type, a wrong reading or a wrong conversion can all inflate the bill.
How the conversion works
Units used = this reading minus last reading.
Imperial meter (cubic feet)? Multiply by 2.83 to get cubic metres.
Multiply by the volume correction factor (1.02264).
Multiply by the calorific value shown on your bill (usually around 39 to 40).
Divide by 3.6. That's your kWh.
Then multiply kWh by your unit rate, add the daily standing charge for each day, and add VAT at 5%. Gas still carries 5% VAT: the VAT cut from October 2026 is for electricity only.
Watch out: if your meter is metric but you're billed as imperial, the bill is about 2.8 times too high.
Frequently asked questions
What is a normal gas bill?
Ofgem's typical home uses about 11,500 kWh of gas a year, most of it in winter.
How do I know if my meter is metric or imperial?
Metric meters show "M3"; imperial meters show "ft3" or "cubic feet".
