We use cookies to allow us and selected partners to improve your experience and our advertising. By continuing to browse you consent to our use of cookies. You can understand more and change your cookies preferences here.

Coronavirus Read our latest advice
Reviews based on facts
Our rigorous tests find the facts, and our impartial reviews tell you the truth about how products perform. First month £5, then £9.99 per month, cancel anytime.
Try Which?
29 October 2020

How to buy the best dehumidifier

Looking for the best dehumidifier to help tackle condensation, damp and mould? We'll help you find the best dehumidifier for you.
Christina Woodger

If you’re noticing water stains on your walls or ceiling, condensation on your windows, mould spores lurking in your shower or a general musty smell, it's time to buy a dehumidifier. Buy the wrong one, though, and it won't do much to tackle your mould problem. 

Read on to find out what your options are, including whether you need a refrigerant (compressor) or desiccant dehumidifier, plus features to look for. 

We'll also help you avoid overspending or ending up with a dehumidifier that's not suited to your needs and simply won't draw water from the air successfully. Whether you're on a tight budget or prepared to spend more, we'll help you find the most appropriate dehumidifier. 

Best dehumidifiers for 2020

We’ve tested a range of dehumidifiers from different brands, including Ebac, Meaco and DeLonghi, to uncover the best dehumidifiers. 

Sign up to reveal product image
Best Buy

This versatile dehumidifier works as well in warm as in cold rooms. It's compact and easily portable, too.

Sign up to reveal product
First month only £5, then £9.99 per month, cancel any time
Already a member? Log in
Sign up to reveal product image
Best Buy

This dehumidifier is energy-efficient, easy to use and - most importantly - great at extracting water.

Sign up to reveal product
First month only £5, then £9.99 per month, cancel any time
Already a member? Log in
Sign up to reveal product image
Best Buy

This dehumidifier has been on the market a while, but it's still one of the best. It's nice and quiet, too.

Sign up to reveal product
First month only £5, then £9.99 per month, cancel any time
Already a member? Log in
Sign up to reveal product image
Best Buy

Proof that you don't need to spend the earth for a good dehumidifier. It pulls water from the air swiftly in warmer rooms, it runs quietly and it's energy-efficient compared to many we've tested. Like many refrigerants, it doesn't work so well in colder rooms, due to the technology involved.

Sign up to reveal product
First month only £5, then £9.99 per month, cancel any time
Already a member? Log in
Sign up to reveal product image
Best Buy

The Inventor EVA II Pro Wi-Fi dehumidifier has plenty of features, including an ioniser mode to refresh stuffy rooms and remove odours. It's wi-fi compatible and can be controlled from your smartphone, but with so many features is it still easy to use? Our review explains how well this dehumidifier did in our stringent lab tests.

Sign up to reveal product
First month only £5, then £9.99 per month, cancel any time
Already a member? Log in

Last checked October 2020

Video: how to buy the best dehumidifier

Watch our video to help you decide which type of dehumidifier is right for you.

Read below for more information on how to choose the best dehumidifier for you, as well as how much you should spend. Know what you want already? Head over to our dehumidifier reviews.

Refrigerant and desiccant dehumidifiers - what’s the difference?

There are two main types of domestic dehumidifier – refrigerant and desiccant. As we explain below, they use different technology. Each type has its advantages.

Refrigerant (or compressor) dehumidifiers

These work by creating a cold surface. When warm, damp air comes into contact with the cold surface, condensation forms and drips into the water tank. Refrigerant dehumidifiers are the most common type in the UK. They're generally only effective in a heated room in the house because, if the temperature drops too low, the coils inside them can freeze over. However, we've found some that work well in lower temperatures, too. 

Desiccant dehumidifiers 

Desiccant dehumidifiers use an absorbent material to extract water from the air, in a similar way to a sponge. The desiccant is regenerated by an internal heater, and the moisture drips into the water condenser. 

Desiccant dehumidifiers will often work more effectively than refrigerant dehumidifiers in colder temperatures of 15°C or less. That's because refrigerant dehumidifiers work best at higher temperatures and higher humidities. 

The inside of a refrigerant dehumidifier needs to be colder than the air within the room – and the colder the room, the harder the dehumidifier has to work to create that cold surface. So, if you're looking for a dehumidifier for an unheated garage, conservatory or other out-building, you should generally opt for a desiccant. 

That said, we've found some versatile refrigerant models that work fantastically in chilly conditions.

Take a look at our best dehumidifiers to discover the models that Which? recommends.

How much do dehumidifiers cost?

Dehumidifiers can cost anything from around £40 to £450. The amount you spend largely depends on the dehumidifier’s capacity and any extra features it comes with.

Cheap vs expensive dehumidifiers

If you’re already spending plenty on heating, having to fork out for a dehumidifier can feel like a kick in the teeth. So can you get away with a cheap one? There are a few factors to consider.

The cheapest dehumidifiers usually have a smaller capacity. Dehumidifiers that cost less than £130 tend to have a capacity of 10 litres or less.

Cheaper dehumidifiers also tend to have fewer features than more expensive ones. A cheap dehumidifier is less likely to have wheels or a laundry setting. 

Most dehumidifiers have a built-in humidistat or auto setting regardless of price, however. And most have a digital or analogue display, although a handful just have an on/off switch.

Cheap dehumidifiers aren't necessarily less reliable than more expensive ones. We asked more than 500 dehumidifier owners to tell us how long their machines had lasted, and what had gone wrong if they broke down. As a general rule, dehumidifiers were rated highly for their reliability, meaning they’re unlikely to develop faults. 

The dehumidifier brand that was rated least reliable still had 72% of products staying fault-free after six years – which is better than many other home appliances.

You'll need to spend at least £130 to get a reasonable dehumidifier: those we've tested below that price haven't proven very effective. Beyond that, though, there isn't any correlation between price and performance. 

One dehumidifier we tested, for example, costs nearly £270 but scores only 50%, as it doesn't tackle humidity as swiftly as many others and is very noisy. Another cost £450 and scored 59%. It's not a terrible model, but you'd certainly be annoyed if you spent that much and then found out you could have spent more than £300 less on a better one: one of our Best Buys costs just £130. 

Want to know which models we're talking about? Check out our list of best dehumidifiers to discover which models are rated as Best Buys. 

How much do dehumidifiers cost to run?

The good news is, you probably don't need to worry too much about a dehumidifier adding enormously to your energy bills. A 250W dehumidifier, running for four hours at a time, twice a week, should cost around £19.50 a year to run. 

That said, some are much slower at extracting water from the air than others. This means you’ll have to use them for longer, which will increase the amount of energy you use.

What size or capacity dehumidifier?

A dehumidifier's size or capacity describes how many litres of water it's able to extract from the air each day, rather than its physical size or the capacity of its water tank (although dehumidifiers with a larger extraction rate are often larger and contain larger tanks). 

The best-sized dehumidifier for your needs depends on the size of the space you want to use it in. As a general rule, if you're looking for a dehumidifier to dry out your whole home, you'll need a model with a larger capacity. You can use the following table to to get an idea of what capacity dehumidifier you need. 

Dehumidifier capacity chart - moderate damp
45 square metres 90 square metres 135 square metres 180 square metres 225 square metres
6.5 litres 9.5 litres 12.5 litres 15.5 litres 18 litres

These figures are just here to get you started, though. Bear in mind that two dehumidifiers with the same capacity claims could vary enormously in performance, so the only way to be sure is to check our reviews. 

You should also bear in mind that manufacturer claims about capacity (water extraction rate) are often based on conditions you're unlikely to experience in your home. For refrigerant dehumidifiers, manufacturers frequently base their claims on 30ºC and 80% relative humidity – conditions which better represent a tropical rainforest than a typical British home. 

That's because the higher the temperature and the higher the humidity level, the more effectively a refrigerant dehumidifier will work. So, if a dehumidifier has a capacity of 18 litres, this doesn't mean you can expect it to extract 18 litres of water a day from your home. 

We test all dehumidifiers in more realistic conditions to help you pick the right one. We measure how much water each dehumidifier pulls from the air at 21ºC and 10ºC, both with 59% relative humidity.

Small dehumidifiers

If you've got a tiny home, you won't want a great, hulking dehumidifier taking up precious square footage. 

The smallest dehumidifiers have a capacity of 7-10 litres, though you'll see many more at 10 litres than 7 litres. Size wise, these smaller models will range between 18cm x 38cm x 18cm, and 36cm x 55cm x 33cm (w x h x d). 

What features do dehumidifiers have?

Here are some of the features to consider when shopping for a dehumidifier:

  • Continuous drain facility Many dehumidifiers allow you to connect a hose and flush the collected water directly away to a low-level drain. This will save you from emptying the water tank yourself, or prevent the machine from getting full and switching off if you're not around to empty it - but you need to think through how this is going to work in your home. Dehumidifiers with this function often don’t come with a hose in the box, so you’ll have to buy it separately.
  • Auto setting or in-built humidistat This monitors moisture levels in the air and adjusts the dehumidifier to maintain the humidity level you’ve selected. This saves you from repeatedly turning your dehumidifier on and off, as it automatically knows when it needs to work hardest. Head to our dehumidifier reviews to find the models with an effective auto setting.
  • Integrated cord storage For saving space when the dehumidifier isn’t in use, and removing the risk of tripping over a sprawling cable. Not an essential, but nice to have.
  • Timer Allows you to programme the dehumidifier to turn on and/or off after a specified amount of time. This could help you save money if you're on a tariff offering cheaper energy at certain times of day. However, you may find a humidistat more useful.
  • Laundry setting If you don’t have a tumble dryer, and it’s too cold to hang wet clothes outside (or if you don’t have access to a garden or balcony where you could put up a clothes line), then a dehumidifier can help you dry your clothes. Some come with a laundry setting, but really you can use any dehumidifier for this - many laundry settings just whack up the power to max for a set time. Hanging clothes on a radiator can cause condensation, so avoid doing that. Manufacturers say that a dehumidifier will leave your clothes softer than a tumble dryer would, as it doesn’t use heat.
  • Wheels/castors Could come in useful if your dehumidifier is heavy - they can weigh from 6kg to more than 16kg.

Which dehumidifier brand is best?

Some dehumidifier brands routinely do well or badly, while others are a lot more hit and miss. 

Click on the links below to find out how models from different brands fare:

View all Dehumidifiers