Running costs · price cap 1 July to 30 September 2026
How much does a kettle cost to run?
Boiling a full litre of water takes about 0.10 kWh, which costs about 2.6p at the current price cap of 26.11p per kWh. Which? puts the yearly cost for an average household at £38.69, based on boiling a litre twice a day and a minimum fill three times a day.
Prices checked against Ofgem on .
Per litre boiled
2.6p
0.10 kWh
Per mug
0.65p
250 ml
per year
£38.69
Which? average use
Unit rate
26.11p
per kWh, price cap
Kettle running cost by how much you boil
Energy to heat water from 15°C to boiling, ignoring small heat losses. The last column is the cost of doing it once a day for a year.
| Amount | Energy | Per boil | Once a day for a year |
|---|---|---|---|
| One mug (250 ml) | 0.025 kWh | 0.65p | £2.35 |
| Half a litre | 0.049 kWh | 1.3p | £4.71 |
| One litre | 0.099 kWh | 2.6p | £9.42 |
| A full 1.7 litre kettle | 0.168 kWh | 4.4p | £16.01 |
Kettle running cost by electricity price
Monthly and yearly cost at the same usage. Fixed deals vary, so check the unit rate on your bill.
| Tariff | Unit rate | Per month | Per year |
|---|---|---|---|
| 1 July to 30 September 2026 price cap | 26.11p | £3.22 | £38.69 |
| 1 October to 31 December 2026 price cap | 26.32p | £3.25 | £39.00 |
| A 20p per kWh fixed deal | 20p | £2.47 | £29.64 |
| A 24p per kWh fixed deal | 24p | £2.96 | £35.56 |
| A 30p per kWh fixed deal | 30p | £3.70 | £44.45 |
Only boil what you need
A full 1.7 litre kettle costs about 4.4p to boil, against 0.65p for one mug. Over a year of daily cups, boiling a mugful instead of a full kettle saves about £13.66.
Why wattage matters less
A 3,000 W kettle and a 2,200 W kettle need the same energy to boil the same water. The more powerful one just gets there faster, so it costs about the same per boil.
From 1 October
The price cap changes to 26.32p per kWh from 1 October to 31 December 2026. At the usage above, a kettle would cost £39.00 a year, 31p more than now.
Guides and definitions
- Energy price cap explained: rates from 1 October 2026 and your bill (Guide)
- Is Economy 7 worth it? Hours, price cap and the night-use break-even (Guide)
- Standing charge vs unit rate: which energy tariff is cheaper for you? (Guide)
- Economy 7 (Economy 7 is an electricity tariff with seven cheaper off-peak hours, usually overnight, and a dearer daytime rate; Ofgem assumes 42% of use falls off-peak.)
- Typical domestic consumption values (TDCVs) (Typical domestic consumption values are Ofgem's yearly usage figures for a typical home, 2,500 kWh electricity and 9,500 kWh gas from 1 July 2026.)
- Energy price cap (The energy price cap is Ofgem’s limit on unit rates and standing charges for default tariffs; typical bill £1,723 from 1 October 2026.)
- Standing charge (A standing charge is the fixed daily amount on an energy bill, paid whatever you use; the capped average is 54.83p a day for electricity.)
Other appliances
- Washing machine (running costs)
- Dishwasher (running costs)
- Tumble dryer (running costs)
- Electric oven (running costs)
- Air fryer (running costs)
- Fridge freezer (running costs)
- TV (running costs)
- Electric shower (running costs)
- Immersion heater (running costs)
- Electric heater (running costs)
Appliance running cost calculator · Use your own wattage and unit rate
Common questions
How much does it cost to boil a kettle?
About 2.6p per litre, or 4.4p for a full 1.7 litre kettle, at 26.11p per kWh.
How much does a kettle cost to run a year?
About £38.69 for typical use, according to Which? testing.
Is it cheaper to boil water in a kettle or on the hob?
An electric kettle is usually the cheapest way to boil water, because the element sits in the water and little heat escapes. An electric hob heats the pan and the air around it as well.
Sources and assumptions
- Prices use the Ofgem price cap for 1 July to 30 September 2026: 26.11p per kWh, the average for Direct Debit customers in England, Scotland and Wales. Northern Ireland is not covered by the cap.
- Energy use comes from Which? lab tests of typical models. Your own model may use more or less.
- The daily standing charge (57.19p a day) is paid whatever you use, so it is not included.
- Ofgem: energy price cap unit rates and standing charges
- Which?: how much your appliances cost to run (26 August 2026)
These are estimates. Your bill depends on your tariff, your region and how you use the appliance.