Best Air Purifier Under £150 for Bonfire Night 2026: What £99 to £130 Buys, and Why the Smoke Peak Is Smaller Than the Adverts Say
Every air purifier advert this month leans on the same scare: Bonfire Night is coming, the air will be thick with smoke, buy now. The public data is less dramatic than that. And the best air purifier under £150 has almost nothing to do with 5 November anyway.
In This Article
- What Bonfire Night does to the air, and what it doesn't
- The best air purifier under £150: four machines compared
- Doing the room maths yourself
- The filter bill nobody puts on the box
- How Which? separates good from bad, and what it means at this price
- What I'd skip
- Where it goes and when to run it
- Who should save their money
- The verdict
Here’s what the numbers say. Ricardo’s analysis of the 2023 Bonfire Night readings, covering 172 monitoring sites, found clear particle peaks on the evenings of the 4th and 5th. It also found that the daily air quality index stayed in the “low” band throughout.
So no, a £120 box won’t save you from a one-night smoke apocalypse. But it will do something useful for the other 360 days, and that’s the case I’ll make below.
What Bonfire Night does to the air, and what it doesn’t
The peak is real. Ricardo’s report says the median reading hit just under 16 μg/m³ in 2023, against just over 62 in 2018. That’s a fourfold gap between a wet, still year and a bad one, and the authors put the smaller 2023 spike down to “wet weather and relatively low winds”. They’re also careful to say the figures shouldn’t be used to wave away the health effects of fireworks smoke.
Fair enough. But look at what that tells a buyer. The spike lasts an evening or two, and it happens outdoors first. Your purifier only helps if you’re indoors with the windows shut, which is exactly what most of us do on a cold, damp night in November anyway.
My view: don’t buy a purifier for Bonfire Night. Buy one because you’ve got a wood burner, a gas hob, a dusty hallway, or a neighbour who burns wet logs every weekend. Our piece on the 2026 log burner rules covers why that last one is becoming a council matter.
The best air purifier under £150: four machines compared
A quick caveat before the list. I haven’t tested these myself, and Which? keeps its actual test results and Best Buy labels behind a members’ login. What follows draws on the prices Which? lists publicly and on HouseFresh’s measured figures, which it updated this week. Where I’m guessing, I’ll say so.
The number that matters is CADR, the Clean Air Delivery Rate. It’s how much cleaned air a machine pushes out per hour. Which? measures it for every model it tests, and HouseFresh’s advice is to buy on CADR rather than on the brochure. Higher is better, full stop.
Four machines that come in under £150, using HouseFresh’s PM1 CADR figures (that’s the tiny stuff, smoke included):
- AirFanta 3Pro, £118. CADR 600 m³/h, rated for rooms up to 49 m². HouseFresh’s best-value pick. The HEPA plus carbon version costs £130.
- Midea SmartAir Pure Control, £99.99. CADR 326 m³/h, rooms up to 27 m². The cheapest of the four, and the one I’d look at for a bedroom.
- Philips PureProtect Mini 900 Series, £130. CADR 250 m³/h, rooms up to 20 m². Small, branded, easy to find in the shops. The black one costs £149.99.
- Acer Acerpure Pro P2, £114. Listed by Which? at that price. I can’t give you a CADR for it because the figure isn’t public, so treat it as unproven.
On paper, the AirFanta is the obvious winner. It has more than double the CADR of the Philips for less money. The catch is that it only takes the manufacturer’s own filters, so you’re tied to one supplier. That’s a bit of a faff if they ever stop making them.
The Philips is the one most people will walk out of a shop with, because the name is familiar. It’s fine. But paying £130 for 250 m³/h when £118 gets you 600 is the sort of brand tax I’d skip.
Doing the room maths yourself
HouseFresh quotes the US EPA’s rule of thumb: a room needs at least 4.8 air changes per hour. You can work that out on the back of an envelope.
Multiply length by width by ceiling height to get the room’s volume in cubic metres. Then multiply by 4.8. The answer is the CADR you want, as a minimum.
A 4m by 4.5m living room with a 2.4m ceiling is 43.2 m³. Times 4.8 gives about 207 m³/h. That’s my arithmetic, not a figure from either source, but it lines up with HouseFresh’s room ratings. Both the Midea and the AirFanta clear it easily. The Philips Mini clears it with a little to spare, and that’s before you’ve left a door open.
Now try a 6m by 5m open-plan space. That’s 72 m³, so you’d want roughly 346 m³/h. The Midea falls short. The AirFanta doesn’t. And the Philips Mini isn’t remotely in the conversation.
The filter bill nobody puts on the box
Which? measured the electricity cost of every purifier it tested and found a spread from as little as £6 a year to as much as £45. That’s the machine running flat out for 12 hours, according to the page. So power isn’t the worry.
Filters are. HouseFresh lists replacement sets at £69 for the Winix Zero S and £69.99 for the Coway Airmega 350, and the cheapest long-term cost it names is £34.72 a year for the CleanAirKits Luggable XL Ultra. Those are pricier machines, but they show the pattern. A filter set can cost more than half what you paid for a budget purifier.
I haven’t found a public price for the budget models’ filters, so I can’t give you the true annual cost of the AirFanta or the Midea. Before you buy any of them, find the replacement filter on the retailer’s site and check what it costs and how long it’s meant to last. If you can’t find one, don’t buy the machine.
And do the sums against what else you’re spending to keep the house comfortable this winter. Our energy saving gadgets piece has a list of what pays back and what doesn’t. A purifier isn’t on it, because it won’t save you a penny. It’s a comfort purchase, and it should be priced like one.
How Which? separates good from bad, and what it means at this price
Which? tests purifiers in ways that most shop-floor demos never will. It measures CADR for each machine, noise on both the highest and lowest settings, and the energy used over 12 hours on full power. It also ages the filters by exposing them to the smoke from 100 cigarettes, so a purifier that looks great when new but clogs quickly gets found out.
The outcome is a wide spread. Which? says poor performers are “significantly slower, trap fewer particles, make more noise and use more energy”. It lists four Don’t Buys, though it doesn’t name them publicly. It also says one Great Value model is more than £150 cheaper than one of its Best Buys, which tells you the cheap end of this market isn’t automatically the weak end.
That’s the encouraging bit. The less encouraging bit is that I can’t tell you which cheap model that is. It might be the Acer at £114, or the Blueair Blue Max 3250i at £169 (just over our cap), or something else on the list. If you’ve got a Which? login, the test table will settle it in a couple of minutes. If you haven’t, HouseFresh’s CADR figures are the best free guide I know of.
For reference, the other prices Which? shows are Philips PureProtect Mini at £130, the Philips PureProtect 3200 at £260, the Blueair Blue Signature at £309 and the Levoit Sprout at £280. IKEA’s Uppatvind and Fornuftig are listed at £29 and £50, and I’d be lying if I said I knew how they perform. They’re cheap enough to try, but I wouldn’t put either in a room you’d planned to rely on.
What I’d skip
Anything described as “HEPA-type” or “HEPA-style”. Which? is blunt about this. Under EU standards, a filter has to remove at least 99.95% of particles 0.3 μm across to call itself HEPA, and it warns buyers to watch for marketing names that sound close but haven’t passed that bar.
Skip the £300-plus models too, unless you’ve got a very large room. The Levoit Core 600S lists at £299.99 and the CleanAirKits Luggable XL Ultra at £299. They’re good machines. HouseFresh’s CADR for the Levoit’s 637 m³/h against the AirFanta’s 600, so you’d be paying nearly £180 more for a gap of 37.
The Winix Zero S at £185 is HouseFresh’s best for most people, at CADR 423. It’s above our £150 cap, and I’d only stretch to it if noise matters. HouseFresh measured it at 35.6 dBA on its lowest speed and 57.4 dBA on speed four, which is a big difference. A purifier you switch off because it’s too loud cleans nothing.
And if smoke is the reason you’re buying, Which? says you’ll need a carbon filter as well as a HEPA one. My reading is that HEPA catches the particles and carbon deals with the smell, so a purifier with only HEPA could clear the haze and leave the bonfire whiff behind. That’s an inference, not something I’ve measured.
Where it goes and when to run it
This part is common sense rather than anything I’ve seen measured. Put it in the room where you spend the most time with the door shut. Run it before the smoke arrives, not after, and keep the windows closed while it’s going.
For a bedroom, the Midea is the one I’d pick on size and price. Check the noise figure first, because bedrooms are where a loud machine gets unplugged by the second night. Our guide to the best electric blanket is worth a read if you’re planning to keep the heating low and the bedroom window shut this winter.
One more honest point. If your actual problem is damp, a purifier doesn’thing for it. It filters particles, not moisture. For condensation and mould you want a dehumidifier, and we’ve covered the best dehumidifier for damp in detail. Buying the wrong box is the most common mistake in this category.
Who should save their money
If you live somewhere with no obvious source of smoke or dust, no pets, a modern extractor fan and windows you open every morning, you probably don’t need one. A purifier is a tool for a specific problem. Buying it as a general wellness gadget is how they end up on top of wardrobes.
The same goes if you’re in a rented flat and your problem is a damp bathroom or a drying rack in the hall. That’s a moisture problem, and our look at dehumidifiers for drying clothes will be more use to you. And if your worry is the cost of heating the room you’re sitting in, the cheapest electric heater to run is the better read.
But if you burn logs, cook on gas, live near a busy road or someone in the house is sensitive to dust and smoke, a purifier in the right room makes sense. And at £100 to £130 it’s no longer a luxury.
The verdict
If you’ve got one main living space of up to about 45 m² and £120 to spend, the AirFanta 3Pro is the machine the evidence points to. Its CADR is the highest in the price band, and the price is hard to argue with. Just check the filter cost first.
For a bedroom or a small room, the £99.99 Midea is the sensible pick. For anyone who wants a name they recognise, the Philips Mini is fine. It’s just not good value.
The Which? figures are the ones to wait for if you want a second opinion. The paywalled Best Buy list will be out for anyone with a login, and I’d check it before spending anything over £100. I’m guessing the budget picks I’ve named will appear there, but I can’t confirm that.
Bonfire Night will pass in a night or two and the air will clear, with or without a purifier. So here’s the question worth asking before you buy: what is it you actually want out of the air in your home between now and March?
Sources: Which?, Best air purifiers 2026; HouseFresh, The best air purifiers in the UK; Ricardo, Air Quality on Bonfire Night 2023. Prices as listed on those pages on 23 October 2026 and subject to change.
