Energy Bill Calculator

The Energy Bill Calculator estimates your full annual gas and electricity costs based on Ofgem Energy Price Cap rates and your household usage. For Q1 2025, the cap sets a typical dual-fuel direct-debit bill at around £1,738 a year for a medium household using 2,700 kWh of electricity and 11,500 kWh of gas. The cap limits the unit rates and standing charges suppliers can charge — it does not cap the total bill, so high usage means a higher overall cost. Enter your annual or monthly kWh usage for gas and electricity (find these on a recent bill, your smart meter in-home display, or your supplier online account) along with the unit rates and standing charges shown on your current tariff. The calculator returns annual, quarterly, monthly and weekly cost estimates, and breaks down the standing charge component so you can see how much you pay even before using any energy. All figures include the reduced 5% domestic VAT on energy. The price cap is reviewed every three months — January, April, July and October — and reflects wholesale energy markets, network costs, supplier operating costs and policy charges. Fixed tariffs from suppliers may sit slightly below the cap when wholesale markets are calm, providing 12-24 months of price certainty. Compare your calculator estimate against any fixed deal to decide if locking in is worthwhile. Households on Economy 7 should enter separate day and night rates: the night rate is typically half the day rate, making EVs, storage heaters, dishwashers and laundry much cheaper to run overnight. If your estimate is significantly higher than past bills, check for estimated meter readings (submit actuals monthly), draught-proof your home, fit a smart thermostat (saving around £100/year per 1°C lower), and check eligibility for the Warm Home Discount (£150) or the Boiler Upgrade Scheme (£7,500 toward a heat pump).