Gas Bill Calculator
Estimate your gas bill from your kWh usage using the Ofgem price cap — 6.29p per unit plus a 34.03p daily standing charge for 2025 — over any billing period.
Gas bill estimate
Unit rate + standing charge, Ofgem cap 2025.
Based on the Ofgem gas price cap (6.29p/kWh, 34.03p/day). Your tariff and region may differ.
How a UK gas bill is worked out
Your gas bill has two parts: a unit rate charged on every kilowatt-hour (kWh) of gas you burn, and a daily standing charge you pay just for being connected — even if you use no gas. This calculator adds both together over your billing period and includes VAT-inclusive Ofgem price-cap defaults you can edit to match your own tariff.
At the 2025 Ofgem cap of 6.29p per kWh and a 34.03p daily standing charge, using 1,000 kWh of gas over a 30-day month costs about £62.90 of gas plus £10.21 standing charge = £73.11.
2025 Ofgem gas price cap
| Charge | Oct–Dec 2025 |
|---|---|
| Gas unit rate | 6.29p / kWh |
| Gas standing charge | 34.03p / day |
| m³ to kWh factor | × 11.2 (approx.) |
| Typical annual gas use | ≈ 11,500 kWh |
Source: Ofgem — energy price cap Oct–Dec 2025.
Converting gas units to kWh
If your meter reads in cubic metres (m³), multiply by roughly 11.2 to get kWh (the exact factor uses the calorific value and a 1.02264 correction on your bill). Older meters reading in hundreds of cubic feet need an extra ×2.83 step. For a combined gas-and-electricity view, see our energy bill calculator.
Frequently asked questions
How is a gas bill calculated?
Multiply your gas used in kWh by the unit rate, then add the daily standing charge multiplied by the number of days. For example, 1,000 kWh at 6.29p plus 30 days at 34.03p is about £73.11 including VAT.
What is the price of gas per kWh in 2025?
Under the Ofgem price cap for October to December 2025, gas is capped at an average of 6.29p per kWh, with a daily standing charge of 34.03p. Rates vary slightly by region and by payment method.
How do I convert gas m³ to kWh?
Multiply cubic metres by about 11.2 to get kWh. The precise factor on your bill uses the gas calorific value and a 1.02264 volume correction, but 11.2 is a good estimate for a quick check.
What is the gas standing charge?
The standing charge is a fixed daily fee — about 34.03p a day in late 2025 — that covers the cost of connecting your home to the gas network. You pay it even in months when you use little or no gas.
Why is my gas bill higher in winter?
Heating and hot water dominate gas use, so winter consumption can be several times higher than summer. The unit rate and standing charge stay the same, but you burn far more kWh in cold months.