Dry indoor air is a winter problem with a cheap fix and an expensive one. The expensive one is a Dyson Humidify+Cool, £699 at John Lewis. The cheap one starts around thirty pounds.
That is a gap of roughly twenty times, which is large enough that the sensible reaction is suspicion rather than excitement. So the question worth answering is not whether a cheap humidifier is cheaper. It is what the other six hundred and sixty pounds is actually buying.
The one thing a cheap humidifier cannot do
A Dyson Humidify+Cool is not a humidifier. It is three machines sharing one body: an air purifier, a humidifier, and a fan.
The purifier is the part that matters here. Dyson's own listing describes three-stage filtration, HEPA H13 with a carbon layer and catalytic oxidisation, aimed at dust, odours and allergens. None of the units below do any of that. They add moisture to the air and nothing else. If you have hay fever or a dust allergy, or you live on a main road and want something done about the air rather than the dryness, a cheap humidifier does not replace a purifier. We would rather say that at the top than bury it.
Your problem might instead be a dry throat every morning through winter, or static, or a nursery that gets uncomfortable when the heating is on. Then humidifying is the whole job. That job costs about thirty pounds.
The fan is the third function and the easiest to replace. A separate fan costs a fraction of the difference.
Our picks
Homvana Cool Mist Humidifier, 1.5L: £29.99
The cheapest way to find out whether humidifying actually helps you. A 1.5 litre cool mist tank is small, which means refilling it more often, but it also means it fits on a bedside table rather than needing floor space.
Verdict: Buy this one if you are not yet sure the problem is the air.
Levoit Humidifier for Bedroom, 25dB Top Fill: £33.99
Two details here are worth more than the price difference. Rated at 25dB, which matters because a humidifier that keeps you awake is worse than dry air. And top fill, meaning you pour a jug into it where it stands, rather than carrying a full tank to the tap and back.
Verdict: The sensible default, and the one most people should buy.
Levoit Smart Humidifier, 4.2L Top Fill, 21dB: £49.98
A 4.2 litre tank and a quieter 21dB rating. The tank is the real upgrade: bigger means fewer refills, which is the thing that makes people stop using a humidifier by February.
Verdict: Worth the step up if you will run it every night.
Levoit Smart Warm & Cool Mist, Voice Control: £99.99
Warm mist as well as cool, plus app and voice control. This is the closest of the four to what a premium machine offers, and still a fraction of one.
Verdict: The one to buy if you want the features rather than just the function.
How they compare
| Humidifies | Purifies the air | Fan | Price | |
|---|---|---|---|---|
| Homvana 1.5L | Yes, cool mist | No | No | £29.99 |
| Levoit 25dB | Yes, cool mist | No | No | £33.99 |
| Levoit 4.2L Smart | Yes, cool mist | No | No | £49.98 |
| Levoit Warm & Cool | Yes, warm and cool | No | No | £99.99 |
| Dyson Humidify+Cool | Yes | Yes, HEPA H13 | Yes | £699 |
The middle column is the honest answer to why a Dyson costs what it costs. Read across it before deciding the price gap is absurd.
Frequently asked
Will a cheap humidifier clean my air? No. Not one of these filters anything. They add water vapour. A machine that purifies as well is a different product and it costs several times more, which is exactly the point of the table above.
Is a Dyson humidifier a rip-off then? No. Calling it one would be easy and wrong. It genuinely does three jobs, and doing them in one machine on one plug in one bit of floor space has real value. What we would say is that plenty of people buy one for a problem that only needs the cheapest of the three functions.
What about running costs? All of them need cleaning and descaling, and that is not optional: a neglected humidifier grows things you then breathe. Dyson's own pitch leans heavily on hygiene for this reason. On a cheap unit you do the work yourself instead.
How big a tank do I need? Bigger tanks mean fewer refills, and refill fatigue is the reason most humidifiers end up in a cupboard by spring. If it is going in a bedroom you use every night, size up.
Do I need warm mist? Not usually. It is more comfortable in a cold room and uses more power. It is a preference, not a requirement.
How we priced this
Our own prices are read live from the retailer as this page loads, so they are current rather than whatever they were on the day this was written.
The Dyson figure is its listed price at John Lewis, linked above, not an RRP from a box and not a number we carried over from an older article. We have compared against what it actually sells for.
We have not tested any of these against each other or measured their output. What is checkable is what each one costs, what each one claims to do, and which of them filter air, which is the difference that decides this purchase. Tank sizes and noise ratings above are the manufacturers' own figures, taken from the product listings.
The bottom line
If you want purified air, buy the purifier. Nothing in this list is a substitute for one, and a cheap humidifier bought for that reason is money wasted.
If you want moisture in a dry room, the Levoit 25dB does that job for the price of a takeaway, and the 4.2L version does it for longer between refills. The rest of what a Dyson does is real, and you should only pay for it if you actually want it.
Elsewhere, the same question comes up with Dyson's vacuums, and everything we track for the house is under Home & Kitchen.