Electricity Bill Calculator

We've created this electricity bill calculator to help you estimate how much you should be expecting to pay for your electricity bill over any set period of time.

This may be because you are moving home and want to work out how much more or less you may have to pay, or maybe you are looking to switch tariffs and see how much you could save on your utility bills.

Whatever your reason, keep reading to see how to use our free electricity bill calculator and find out what you need to know.

How to use our electricity bill calculator

You need to start by deciding how many days you want to look at, one day, one week, one year or anything in between.

Next, enter the electricity used over whichever unit you selected — for example, kWh per month when the period is months. Use a recent bill or meter total where possible; the Ofgem bands below are benchmarks, not household estimates.

The next two pieces of information you will need to get from your utility bill will differ depending on your energy supplier and tariff.

Your unit rate is how much you pay for each unit of electricity, and your standing charge is a fixed amount you pay per day regardless of how much energy is used.

Once you put all these details in, you will automatically see a breakdown of your total unit charge over the period you set, the total cost of your standing charge, and your overall bill for that period of time.

What is a Unit of Electricity?

One unit of electricity is one kilowatt-hour (kWh): 1,000 watts used for one hour. The following are exact arithmetic examples if the device draws the stated power constantly:

Examples equal to 1 kWh

• A 100 W device running at that constant power for 10 hours.
• A 500 W device running at that constant power for 2 hours.
• A 1 kW device running at that constant power for 1 hour.
• A 2 kW device running at that constant power for 30 minutes.
• A 3 kW device running at that constant power for 20 minutes.

The total units you consume are recorded on your electricity meter and are used to calculate your electricity bill, based on the unit rate charged by your energy provider.

What is a Daily Standing Charge?

A daily standing charge is the fixed pence-per-day part of your tariff, charged regardless of how much electricity you use. This calculator multiplies the rate you enter by the number of calendar days and adds that to the unit-rate cost of the electricity entered.

How much electricity a typical UK household uses

If you do not know your own usage, Ofgem publishes Typical Domestic Consumption Values — three bands rather than a figure per bedroom. The medium band is the one used to quote a typical annual bill, including under the price cap.

Low is a flat or a small, well-insulated home, often one or two people; Medium is the figure quoted as “typical” across the industry, including on the price cap; High is a larger home, or more people, or both.

Source: Ofgem, Review of typical domestic consumption values, in force since 1 July 2026 (decision ofgem-tdcv-2026). The monthly and daily columns are the annual figure divided by 12 and by 365; Ofgem publishes the annual figure only. These are single-rate figures. An Economy 7 or other multi-register meter has its own set, and a household on one uses about a third more.

These values changed on 1 July 2026. The medium band was 2,700 kWh before that, so a bill quoted on the older figure is not comparable — the assumption moved, not the household. Real usage varies with the age of the property, how it is heated, how many people live there and the time of year, and is far higher in winter than any annual average implies.

We also have a gas bill calculator and an energy bill calculator available (to calculate a combined gas and electricity bill).