How much energy does a washing machine need?
There is no single figure: energy use is measured per 100 cycles on the eco 40-60 programme and varies by model and load size. Across ApplianceBench's qualified set the median is 65 kWh per 100 cycles, so a typical machine uses roughly 0.65 kWh per cycle.
Ask how much energy a washing machine needs and the honest answer starts with a question back: which programme, and how full is the drum? Modern labels do not quote a single lifetime figure. They quote energy per 100 cycles, tested on the eco 40-60 programme, which is the standard cycle the regulations use for comparison. That figure is the one worth hunting for when you compare two machines.
[3][2]What the number on the label means
The label's kWh-per-100-cycles value comes from laboratory testing, not from your laundry basket. It reflects the eco 40-60 programme run at the machine's rated capacity, at half capacity, and at a quarter capacity, with those results combined into a weighted figure. So the published number already blends full and part loads, which is why real-world bills drift up or down depending on your habits.
[2]Across ApplianceBench's qualified comparison set, the median washing machine sits at 65 kWh per 100 cycles, which works out to about 0.65 kWh per cycle. Treat that as a midpoint for orientation, not a guarantee: individual models sit either side of it, and the exact figure for the machine you are considering is on its own record.
[3]A concrete comparison
Suppose, purely as a hypothetical, you are choosing between a 7 kg machine and a 9 kg machine with identical per-cycle figures. The larger drum washes more clothes per cycle, so a household that fills it runs fewer cycles for the same amount of laundry. Conversely, someone who habitually runs half loads on a big machine pays for capacity they never use. The regulations recognise this by weighting consumption at full, half and quarter loads rather than trusting a single full-drum test. Capacity, in other words, changes the maths even when the label numbers look similar.
[2]How the efficiency class is built
The letter class is not just the raw kWh figure. Under the Ecodesign for Energy-Related Products and Energy Information Regulations 2021, a machine's weighted energy consumption on the eco 40-60 programme is compared against a standard cycle energy consumption calculated from its rated capacity, giving an energy efficiency index. Two machines with the same index can therefore carry different kWh numbers if their capacities differ, which is why the letter alone never tells the whole story.
[2]A mistake worth avoiding
The classic error is comparing the label figure of one machine against the annual estimate of another, or mixing figures from different test regimes. Energy labels from different markets use different declarations and test contexts, so figures should never be averaged or swapped. Keep the exact model number, its kWh-per-100-cycles value and its capacity together, and compare like with like.
[3]Turning kWh into pounds
Once you have the certified figure, the useful next move is cost. Multiply the kWh per 100 cycles by your own electricity rate, then scale by how often you actually wash. ApplianceBench's running-cost calculator lets you enter your tariff and ownership period so the estimate reflects your bill rather than a generic average. If the model you are researching has no published energy figure, that gap stays blank rather than being guessed, and the honest step is to check the manufacturer's specification sheet for the exact model code before trusting any number.
[3]Sources and dates
- https://energysavingtrust.org.uk/advice/home-appliances/ · accessed 2026-10-18
- https://www.legislation.gov.uk/uksi/2021/745/schedule/10/crossheading/energy-efficiency-index-of-household-washing-machines-and-the-washing-cycle-of-household-washerdryers-eeiw/made · accessed 2026-10-18
- https://appliancebench.com/ · accessed 2026-10-18