Gas bills and gas meters can use different units
A gas bill commonly expresses billed energy in kWh even when the meter shows volume. The supplier converts the meter reading using bill-specific factors before applying the unit rate.
Use the conversion shown on the bill
Check the meter reading, correction factor, calorific value and conversion line where the statement provides them. Do not copy a raw meter-unit number into a kWh calculator without checking the units.
Calculate only what the figures support
A kWh multiplied by a pence-per-kWh rate gives a usage-cost illustration. It does not recreate standing charges, corrections, adjustments or the supplier’s full bill calculation.
If the conversion looks unusual
Keep the statement and the meter reading together and ask the supplier which units and factors were used. The gas cost calculator is useful after you have identified the billed kWh.