Electricity Cost Calculator UK
Wondering how much it costs to run your kettle, heater or any other electrical appliance? Our free electricity cost calculator uses the latest Ofgem price cap rate of 24.5p per kWh to give you an accurate breakdown of running costs per use, per day, per week, per month and per year. Simply enter the wattage of your appliance, how long you use it each day and how many days per week it runs. The calculator does the rest instantly.
Understanding your electricity costs is the first step towards cutting your energy bills. With UK households spending an average of over £800 a year on electricity alone, even small changes in usage habits can add up to meaningful savings. Whether you are comparing the cost of running a tumble dryer versus a heated airer, or checking whether it is cheaper to use a microwave or an oven, this tool gives you the figures you need. All rates are pre-filled with the current Ofgem cap, but you can enter a custom unit rate if you are on a fixed tariff or economy meter.
How UK Electricity Costs Are Calculated
Every electrical appliance has a power rating measured in watts (W). To work out the running cost, you convert watts to kilowatts by dividing by 1,000, then multiply by the number of hours you use the appliance. This gives you the energy consumed in kilowatt-hours (kWh). Multiply the kWh figure by your electricity unit rate and you have the cost in pence. For example, a 3,000W kettle used for 5 minutes consumes 0.25 kWh, costing around 6p at the current Ofgem cap rate.
The Ofgem energy price cap, updated quarterly, sets the maximum unit rate and standing charge that suppliers can charge customers on standard variable tariffs. As of April 2026, the cap stands at 24.5p per kWh for electricity. You can check the latest cap rates directly on the Ofgem website.
Tips to Reduce Your Electricity Bills
Small behavioural changes can make a surprisingly large difference. Only boiling the water you need, switching to LED bulbs, using a washing machine at 30 degrees and avoiding standby power drain are all easy wins. If you are on a time-of-use tariff such as Economy 7, running high-consumption appliances overnight can cut costs significantly.
For a broader view of your household energy spending, try our appliance running cost calculator to compare multiple devices side by side, or use the gas usage calculator to see how your gas and electricity bills stack up against each other.
Understanding Your Energy Bill
Your electricity bill is made up of two main charges: the unit rate (cost per kWh of electricity you use) and the standing charge (a fixed daily fee for maintaining your grid connection, currently 61.64p per day). Even if you use no electricity at all, you still pay the standing charge. Understanding this split helps you identify whether your high bills are driven by consumption or simply by the fixed costs of being connected to the grid.