We test almost 100 washing machines each year, but what goes on behind the scenes in our thorough washing machine tests? And how do we calculate the score you see for each product?
We’ve tested the latest models to help you choose the best washing machine for your home and budget.
Why our washing machine tests are different
Reviews you read elsewhere might be based on the opinion of the store selling them or one user’s initial feelings about the machine. But they aren’t based on the thorough lab testing and assessments that we carry out at Which? – nobody goes to the lengths we do to find out which are the best washing machines.
For each model and each program, we run three wash cycles. In case of any relevant discrepancy on one of the three cycles, we run an additional two cycles. The Which? overall percentage score you see alongside every review on our site is calculated purely from these test results.
We also buy every single washing machine we test and we don’t accept free samples of any machines.
What are Which? Best Buys and Don't Buys?
Best Buys are awarded to washing machines that impress us most in our tests. A machine must score 77% or more to be a Best Buy. Those that score less than 45% are Don’t Buys.
The best washing machinestick the most important boxes – outstanding stain removal from cottons and manmade fibres, excellent spin cycles, effective rinsing and easy to use.
Don’t Buy washing machinestend to fall down in the most important areas – ineffective stain removal, spinning is too slow to be effective and detergent is left on clothes after the rinse.
What is a Which? Great Value washing machine?
Great Value washing machines combine high quality performance and functionality with a budget-friendly price.
To qualify, a washing machine must first score at least 65% in our tests (they may also qualify as a Best Buy, but this isn't a requirement for a Great Value badge).
They must also be markedly cheaper than the average price for tested models of the same type, whether that is freestanding or integrated.
Finally, each of our Great Value washing machines must achieve at least four out of five stars in our tests for overall cleaning, energy efficiency and water use.
These criteria ensure that any model you see with a Great Value badge will do a great job of keeping your clothes clean without breaking the bank.
If you want to make the most sustainable choice when next buying a washing machine, an Eco Buy is for you.
Eco Buy models will have a lower impact on the environment over their lifetimes than other washing machines.
We calculate this in two ways: how energy efficient they are and how little water they use. But it's also important that the brand achieves a good rating in our reliability survey.
You can expect an Eco Buy to save you money on your energy bills as well as be kinder to the environment.
To be an Eco Buy, a washing machine must have:
A test score of at least 60%
Three stars or more for energy efficiency on both cottons and synthetics washes
Three stars or more for water on both cottons and synthetics washes
Four stars or more for cleaning on both cottons and synthetics washes
The Which? overall test score is a percentage. It only takes into account the results of our tests and ignores price completely. This means that all washing machines are tested on exactly the same scale, so you can compare any washing machine at any price and know how it measures up against its rivals in key areas. All models are tested in the same way, regardless of the manufacturers’ claims.
Weightings and star ratings
A Which? test score is made up of dozens of individual tests, from key factors such as overall cleaning, rinsing efficiency and ease of use, to energy and water use. Behind each of these ratings are dozens of measurements and checks. In the case of ease of use, we carry out more than 50 convenience assessments for each washing machine.
The most important aspects of a washing machine’s performance, such as how well it cleans clothes, will more greatly impact its score than whether the instruction booklet is easy to understand or whether the drum is easy to load and unload.
To keep things simple, the most important scores are shown as star ratings out of five on each washing machine’s Test Results page. This gives an easy-to-compare list of strengths and weaknesses, so you can quickly work out whether a washing machine is right for you.
How the overall test score is calculated
40% - cleaning
15% - rinsing
15% - spin drying
10% - eco score/energy
7.5% - program time
7.5% - how easy it is to use
5% - noise
Our key testing criteria
Below are the key testing categories and how we evaluate each one.
Washing machine overall cleaning - 40%
Key question: Is this washing machine any good at removing stains from clothes?
We've made our cleaning tests tougher than ever, which means Best Buy recommended machines are truly the best on the market for cleaning clothes. We challenge each machine we test to clean a range of stains, including tough-to-shift blood, grease, ink, milk, oil and rust.
We load the machines to 80% of their total capacity when washing on the cottons program and to the full capacity for the synthetics program.
We run our wash tests three times on each program. If any of the wash or energy results are wildly different between tests – or if one test run is much longer or shorter than the others – we will carry out two further test washes. And we do this on both the 40°C cottons program and the 30°C synthetics program.
Washing machine rinsing efficiency - 15%
Key question: Will this washing machine rinse away all of the detergent or will some be left on my clothes?
To measure how well each washing machine removes detergent during the rinse cycle, we take some cotton samples and add them to the cotton load.
At the end of the cycle they are collected with gloves, tweezers and scissors in order not to contaminate them.
These samples are conditioned for 24 hours, weighed and put in a liquid solution in order to extract the detergent residues present before we analyse sulfonate (a type of salt) levels.
A machine that has been awarded one star for rinsing clothes might leave visible traces of detergent on your laundry. Models that provide a three-star rinse should not leave any visible traces of detergent behind. If you can see residue on your clothing, make sure you're not adding too much detergent. Machines that deliver a five-star rinse are the best we've seen at washing away detergent.
Washing machine spin dry - 15%
Key question: Will my laundry be well spun and damp at the end of the wash or badly spun and dripping wet?
It's all well and good if a washing machine can clean clothes, but what about if it leaves them far too wet, making drying your laundry a total nightmare? That's why we measure how much moisture is left in the laundry each machine spins, so we can rate how well it will dry your clothes. We do this by weighing the clothes before they’re loaded into the drum and then again after they’ve been washed.
Washing machine energy use -10%
Key question: Is this washing machine good, bad or indifferent when it comes to energy use?
We record how much energy each machine uses on both of the wash programs we test. We then work out a score for energy based on the amount of laundry they’re washing.
A model with a cavernous 12kg-capacity drum will be tested in the same way as a machine that can only hold 6kg of clothes. The bigger machine is likely to use more energy and water than the smaller machine, so we divide the energy and water used by the capacity of the machine in kilos to evaluate our results fairly for each machine on test.
Because we test washing machines the way you use them, our energy tests reveal the A-rated machines that cost more to run than C-rated models.
Washing machine ease of use - 7.5%
Key question: How easy is this washing machine to load, set and fill with detergent?
You'll want to know your washing machine isn't going to make washing even more of a chore than it has to be. Our ease-of-use assessments will cover reading and understanding the instructions in the manual, loading and unloading the machine, using the detergent drawer, how clear the control panel and display are, selecting a wash program and operating the machine.
We use a team of three lab experts to rate everything on a scale of very easy to very difficult.
Washing machine program length - 7.5%
Key question: How long will it take for this washing machine to wash a load at 40°C?
We time how long the cottons and synthetics 40°C programs take to run, so you aren't stuck with a model that is painfully slow at cleaning your clothes. The star rating is based on the length of the programs and is relative to the capacity of the washing machine.
Washing machine noise - 5%
Key question: Is this washing machine too noisy to live with? Or will it be just fine in my open-plan home?
All washing machines are a little noisy when they're running, but some are far louder than others, to the point where it makes carrying on a conversation or watching TV nearby very hard. That's why we use a panel of five experts to test how noisy each washing machine is during its wash and spin cycles. A very quiet model will earn itself five stars, while a very noisy machine will only pick up one. We also rate how intrusive and annoying the sound is, so that you can avoid particularly frustrating machines.
Washing machine water use
Key question: How much water will this washing machine use?
As with energy, we record every drop of water a washing machine uses during our tests. We produce a star rating for water use, based on how much laundry is being washed in the drum. That way, we’re able to fairly compare large machines with smaller models.
Pick the perfect washing machine with Which? reviews
As you can see from the table below, there is a wide variety in the scores of washing machines in the same price bracket. More-expensive washing machines tend to perform better, as you might expect, but we've found cheaper models that score higher than some much-pricier models. So look beyond price when you’re in the market for a new washing machine.
