Gas Bill Calculator UK

To calculate your gas bill: (1) Take your current meter reading and subtract your previous reading to get the cubic metres used, (2) Convert to kWh by multiplying by 1.02264 × 39.5 ÷ 3.6, (3) Multiply kWh by your unit rate, (4) Add your daily standing charge × number of days, (5) Add 5% VAT. Our gas bill calculator does all this automatically.

Under the UK Energy Price Cap, the current gas unit rate is approximately 6.24p per kWh, with a daily standing charge of around 31.66p. These rates are reviewed quarterly by Ofgem. Your actual rates may differ depending on your tariff and supplier - check your bill or energy account for exact figures.

To convert gas from cubic metres (m³) to kWh: Multiply your usage in m³ by the volume correction factor (1.02264), then multiply by the calorific value (typically 39.5 MJ/m³), and divide by 3.6. The formula is: kWh = m³ × 1.02264 × 39.5 ÷ 3.6. This gives approximately 11.19 kWh per cubic metre.

The standing charge is a fixed daily fee that covers the cost of supplying gas to your property, maintaining the gas network, and meter reading costs. You pay this regardless of how much gas you use. Under the Energy Price Cap, the standing charge is around 31.66p per day (approximately £9.50 per month or £115 per year).

High gas bills can be caused by: inefficient heating system or old boiler, poor home insulation, leaving heating on when not needed, heating unused rooms, incorrect thermostat settings, or an estimated bill being higher than actual usage. Check your meter readings match your bill and consider getting your boiler serviced annually for efficiency.

The calorific value (CV) measures the energy content of gas per cubic metre. UK gas typically has a CV of around 39.5 MJ/m³, though it varies slightly (between 37.5-43 MJ/m³) depending on the gas composition. Your actual CV is shown on your gas bill. This calculator uses 39.5 as a standard average.

Based on Ofgem's typical domestic consumption values, an average UK household uses around 12,000 kWh of gas per year. At current Energy Price Cap rates (6.24p/kWh unit rate + 31.66p/day standing charge + 5% VAT), this works out to approximately £900-950 per year, or around £75-80 per month.