Washer-dryer or washing machine and tumble dryer: which is most cost-effective?
If you're short on space for a standalone tumble dryer, but want to dry your clothes, bedding and towels quickly, should you buy a washer-dryer?
Find out how using washer-dryer compares to a separate washing machine and tumble dryer setup.
We've compared the prices of each and analysed our test data to calculate how much they cost to run, as well as how effectively and efficiently they will wash and dry your laundry.
Already decided on a washer-dryer? We've rounded up the best washer dryers and explain what features to look out for
Is it cheaper to buy a washer-dryer or a washing machine and tumble dryer?
It sounds like a no-brainer that buying two appliances will cost you more than buying one, but actually that's not always true.
At time of writing, it's true that it's cheaper to buy a washer-dryer than a washing machine and tumble dryer, whether you want a Best Buy or you're expanding your search to include all of the models we've tested.
- The cheapest washer-dryer we've tested costs £349. The cheapest washing machine is priced at £200 and the cheapest tumble dryer costs £229 which equals £429 (saving £80 if buying a washer-dryer).
- The cheapest Best Buy washer-dryer we've tested costs £558. The cheapest Best Buy washing machine is £359 and the cheapest Best Buy tumble dryer is £399, which equals £758 in total (saving you £200 if buying a Best Buy washer-dryer).
However, when we've run this pricing analysis in the past, it has at times been cheaper to buy two good standalone models than one washer-dryer – and, even when more expensive, the window has been much narrower.
That's because:
- These machines are often on sale, so you may well get a great deal on a washing machine and tumble dryer.
- There are fewer washer-dryers on the market compared to washing machines and tumble dryers, meaning fewer really good models and less choice for you at the end of the day. Most Best Buy washer-dryers are expensive.
In short, buying a washer-dryer might be cheaper, but don't necessarily assume that's the case. We'd advise checking our reviews and prices at the time that you're ready to buy.
And consider energy and water costs – as well as how much space you have in your home – before deciding.
Looking for a washing machine bargain? We've rounded up the best September deals on washing machines
Do washer-dryers use more energy than washing machines and tumble dryers?
Yes. Based on the new energy price per unit of 34p per kWh, a heat pump tumble dryer will cost you £68 a year to run, on average, and a washing machine will cost you £76 a year, on average. So the two combined will cost you almost £144 a year in running costs.
Your average washer-dryer will also cost you £77, on average, for washing costs and £184 in energy costs for drying – so £261, on average, which is nearly £117 more.
That's based on running the 40ºC cottons program four times a week for a year (for washing machines and washer-dryers) and running the cotton cupboard-dry program on a tumble dryer three times a week for a year.
Clearly, your costs will be higher if you wash or dry your laundry more often than that.
If you decide to go for a washing machine and tumble dryer combo, we strongly recommend getting a heat pump tumble dryer.
Condenser tumble dryers use significantly more energy. You'll be spending, on average, £170 a year in running costs in the scenario we described above, compared to the £68 we calculated for a heat pump.
Find out more about the differences between them and why heat pump tumble dryers cost less to run and use less energy than other tumble dryers.
Do washer-dryers use more water than washing machines and tumble dryers?
On average, a washing machine uses 11.29 litres of water per kilogram of cotton, whereas a washer-dryer uses 12 litres.
That might not sound like a big difference. But if you're washing 5kg of cottons four times a week, for example, you'd be using 738 litres more water across the year with a washer-dryer. The recent water shortage has brought home how much that matters.
You might be surprised to know that washer-dryers also use water for drying clothes – 7.5 litres per kilogram of cottons.
So drying 5kg of cottons three times a week (an average-use scenario, according to our research), you'd be using 5,850 litres of water across the year.
As with energy, you'll have to scale that up if you're washing and drying more often, or down if it's much less.
Do washer-dryers wash well?
Good washer-dryers are pretty much on par with good washing machines when it comes to cleaning.
Both handle stained synthetics well, but can struggle with heavily stained cotton.
They usually take three to four hours for a cottons wash, and one and half to two hours for a synthetics wash.
Do washer-dryers dry well?
For drying, it's a different story. Washer-dryers are nowhere near as good as tumble dryers.
Almost all washer-dryers have sensor-driven automatic drying programs. But these often aren't very accurate. In other words, they over or underestimate how long they need to dry your washing for. Which is not ideal if the clothes you were hoping to wear out are still sopping wet, or have shrunk to no longer fit you.
Washer-dryers usually have a smaller drying capacity than tumble dryers do, although some Best Buy washer-dryers can dry as much as a tumble dryer.
Washer-dryers also have a smaller drying than washing capacity. This means that if you fill your machine to capacity each time you do a wash, in an attempt to run fewer washes, you'll have to take some of it back out before drying.
One small advantage of a washer-dryer is that the water that's extracted from your clothes in the course of drying will be drained away automatically. You won't have to empty it out yourself, as you would with a heat pump or condenser tumble dryer.
Which? washing machine and washer-dryer reviews
We test washing machines, washer-dryers and tumble dryers regularly across the year.
We've just published new reviews of washing machines from AEG, Bosch and Indesit, and washer-dryers from Beko, Blomberg and Haier.
One was a Best Buy, two came close and some left us pretty unimpressed.
One of the washer-dryers we've just tested was painfully slow at drying, taking well over four hours to dry 5kg of cottons.
Some machines struggled with rinsing, leaving noticeable specks of detergent on clothes. And some were incredibly loud on the spin cycle.
Head over to our washing machine reviews and washer-dryer reviews to see test scores for all the most popular models you're likely to come across.
Which? verdict: are washer-dryers any good?
Most washer-dryers do a poor job of drying compared with dedicated tumble dryers.
Go for a separate washing machine and tumble dryer, if you have the budget and the space at home.
As we said before, there are more washing machines and tumble dryers on the market than washer-dryers, so as a bonus you can be choosier when it comes to colour or extra features. Go for a washer-dryer and you're stuck with a more limited pool of models to pick from.
If you've reviewed the options and decided that a washer-dryer is the most suitable option for you, make sure it's one of the best. Best Buy washer-dryers do a much better job of washing and drying clothes than others.
If you don't have room for a tumble dryer, but don't want to buy a washer-dryer, you'll of course need somewhere to hang your wet washing.
The best place to hang it is outdoors, as this reduces the chances of moisture build-up and mould inside your home.
If you don't have an outdoor space where you can hang a clothes line, a heated clothes horse or a dehumidifier can speed up the drying time.
Use our dehumidifier reviews to make sure that you're buying an effective one and read more about avoiding damp problems at home if drying clothes indoors is your only option.
Whether you buy a washing machine and tumble dryer or a washer-dryer, you'll save on water and energy if you choose a Which? Eco Buy.
It can be hard to find appliances that are effective but don't use much energy or water – some are frugal with one or both of these, but just don't clean that well.
Which? Eco buy appliances use energy and water efficiently while also doing a good job. Find out more in our Eco Buy guide.
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Model prices correct as of 9 September 2022. Energy costs were updated on 9 September 2022 in line with the new energy price cap announcement