How much does it cost to run a kettle?

Kettles do not carry an energy rating label, so the cost comes from the power rating on the appliance and how long it runs: watts × hours ÷ 1,000 = kWh, × your electricity price. The defaults are typical; change them to the rating plate on yours.

Where to find the numbers

The power rating is on the base of the kettle; 1,800–2,400 W is usual on a 10 A socket. A full 1.7 L kettle at 3,000 W takes about three and a half minutes to boil; half a litre takes about one. Your electricity price is the unit rate on your bill (c/kWh).

What the figure is based on

Cost per boil depends on how much water you heat, not on the wattage: a faster kettle draws more power for less time. Boiling only what you need is the whole saving.

What changes the cost

• Water volume: boiling a full kettle for one cup uses three to four times the energy needed; the wattage only changes how fast, not how much.
• Boils a day is the lever: each extra full boil is about 0.15–0.2 kWh.
• Starting temperature: cold winter tap water takes more energy to boil than summer water.
• Limescale on the element lengthens boiling time and wastes a little energy.

For a specific model or any other appliance, use the electricity cost calculator.