How much does a washing machine cost per wash?
Most of a wash's cost is heating the water. As a rough guide, a 40°C cotton wash using about 1 kWh costs around 26p at the Ofgem cap rate of 26.32p/kWh. A 30°C wash using about 0.6 kWh costs around 16p. The eco programme, despite taking longer, is often the cheapest of all.
Prices last checked: 26 September 2026 · Source: Ofgem energy price cap, 1 October to 31 December 2026 · Great Britain average, standard variable tariff, paid by Direct Debit
Cost per wash by programme
kWh per wash varies a lot between machines and programmes. The figures below are examples to show the pattern. Your manual often lists energy per programme, and the energy label gives the eco programme's figure.
| Programme | Example energy | Cost per wash | 4 washes a week, per year |
|---|---|---|---|
| Cold / 20°C quick wash | 0.3 kWh | 7.9p | £16.42 |
| 30°C cotton | 0.6 kWh | 16p | £32.85 |
| Eco 40–60 (label programme) | 0.7 kWh | 18p | £38.32 |
| 40°C cotton | 1 kWh | 26p | £54.75 |
| 60°C cotton | 1.5 kWh | 39p | £82.12 |
Why temperature matters more than time
A washing machine's heater is usually rated around 2kW, while the motor that turns the drum uses a small fraction of that. So the cost of a wash is mostly the cost of heating the water to the chosen temperature. Going from 40°C to 30°C cuts the temperature rise from a cold supply substantially, and the energy with it.
That's also why the eco programme looks odd: it can run for three hours or more, yet uses less energy than a short hot wash. It soaks the clothes for longer at a lower temperature, so the heater does less work.
Ways to cut the cost per wash
- Wash at 30°C for everyday loads. Modern detergents are designed to work at low temperatures. Keep 60°C for towels, bedding and heavily soiled items.
- Use Eco when you're not in a hurry.
- Run full loads. A half load uses less than a full one, but not half as much.
- Use a high spin if you'll tumble dry. It costs a little more to spin and saves a lot in the dryer.
- Shift to off-peak if you're on a time-of-use tariff, using the delay-start timer.
Common mistakes
- Assuming short programmes are cheapest. A 30-minute wash at 40°C can use more energy than a 3-hour eco wash.
- Ignoring the tumble dryer. For many households, drying costs far more than washing.
- Counting water in the electricity bill. Water is billed separately by your water company.
Limits of this estimate
Energy per programme varies by machine, load size and water temperature. Costs use the Ofgem cap average unit rate for Great Britain, Direct Debit, standard variable tariff.
Frequently asked questions
How much does a 40 degree wash cost?
About 26p if it uses 1 kWh, which is a reasonable example for a cotton load. Check your manual for your machine's figure.
Is it cheaper to wash at night?
Only on a time-of-use tariff (Economy 7 or an EV or smart tariff). On a single-rate tariff, the price is the same all day.
Does a washing machine use a lot of electricity on standby?
Very little in modern machines. Switching off at the wall saves a few pence a year at most, but it does no harm.