You can buy a functional, genuinely effective air purifier in the UK for under £100. What you give up at this price point is mostly room coverage, smart features and filter longevity — not the core filtration performance.
The thing to be wary of at the cheap end of the market is the difference between True HEPA and "HEPA-type" filters. True HEPA is independently tested to capture 99.97% of particles at 0.3 microns. HEPA-type is a marketing term with no standard — many cheap purifiers use it to imply HEPA performance while actually delivering much less. Every pick on this list uses True HEPA or better.
The other thing to check before buying cheap: replacement filter cost and availability. A £45 purifier that needs a £30 filter every three months is not a budget purifier — it's an expensive one with deferred costs. Check the filter price before you buy.
The Best Budget Air Purifiers
1. Levoit Core 300 — Best Budget Overall
The Core 300 is the standard recommendation for budget air purification and earns that status. At roughly £80, it gives you True HEPA filtration, a meaningful activated carbon layer, and a quiet sleep mode at 24dB. CADR is 187 m³/h and coverage is rated to 80m².
In practice, 80m² is the manufacturer's optimal figure — a good rule is to halve it for the room size where you'll notice the most benefit, which gives you 40m². That covers most UK bedrooms and home offices, and a good proportion of living rooms.
No smart features, no air quality sensor, no Wi-Fi. You turn a dial, pick a speed, leave it running. The filter costs around £25 and lasts six to eight months. Budget £35-40 per year in running consumables.
The physical size is compact — about the height of a large coffee jar — which makes it easy to place on a bedside table or shelf without it becoming a fixture.
Specs
- CADR: 187 m³/h
- Coverage: up to 80m²
- Noise: 24dB (sleep mode)
- Filter: True HEPA + activated carbon + pre-filter
- Filter cost: ~£25, replace every 6-8 months
- Approx. price: ~£80
2. Levoit Core 200S — Best Budget Smart Pick
The Core 200S is smaller than the Core 300 — rated for rooms up to 64m² — and adds Wi-Fi, Alexa and Google Assistant control, plus a sleep mode at a noise level suitable for bedrooms. At around £99, it sits right at the top of the budget bracket, and it's worth it if you want app control or voice integration without spending more.
The smart features are genuine, not gimmicky: the VeSync app lets you set schedules, and you can automate it to run while you're asleep and turn off before you wake up.
No PM2.5 sensor in the Core 200S — you don't get auto mode that reacts to air quality, just scheduled or manual control. That's the main thing you're trading away versus stepping up to the Core 300S at around £120.
Specs
- Coverage: up to 64m²
- Smart: Wi-Fi, Alexa, Google Assistant, app scheduling
- Filter: True HEPA + activated carbon + pre-filter
- Approx. price: ~£99
3. Coway Airmega 100 — Best Budget Pick for Allergy Sufferers
The Coway Airmega 100 is South Korean-made and less well known in the UK than Levoit, but it's a serious product. CADR is 244 m³/h, which is notably higher than the Levoit Core 300's 187 m³/h at a similar or slightly lower price point. It also includes an air quality indicator — a coloured light that reflects detected particle levels — and auto mode that responds to it.
Sleep mode runs at 18.4dB, which is quieter than the Levoit Core 300's 24dB and competitive with the Blueair at this noise level. If you're a light sleeper and want a budget option that won't wake you, this is the pick.
The filter setup is a standard combination of True HEPA and activated carbon. Filter replacement costs are reasonable and Coway has good UK availability.
Specs
- CADR: 244 m³/h
- Noise: 18.4dB (sleep mode)
- Filter: True HEPA + activated carbon
- Air quality indicator: yes (colour-coded)
- Approx. price: ~£80-100
What You Actually Give Up Going Budget
Room coverage. Budget purifiers cover smaller rooms. The Levoit Core 300 is honest about this — its 80m² figure is optimal, not typical. For a 30m² living room you'll still see benefit, but a mid-range purifier (£120-160) will clean the air faster and more thoroughly.
Smart features. No auto mode in the Core 300. No sensor telling you when air quality drops. You run it at a fixed speed and leave it. For many people, this is fine — leave it on medium, forget about it. But if you want the purifier to react intelligently to spikes in particle levels (cooking, coming in from outside, a cat shake), you need a sensor, which costs more.
Filter longevity and cost. Some cheap purifiers have expensive, hard-to-find filters that need frequent replacement. Before buying anything not on this list, search for the replacement filter on Amazon UK and check the cost and availability. If it's over £30 or there are only third-party options, account for that in your total cost of ownership.
What you don't give up. Core filtration performance. A True HEPA filter in a £80 purifier captures particles just as effectively as a True HEPA filter in a £300 one. You're paying more for coverage, sensor intelligence, quieter operation and longer filter life — not for fundamentally better particle capture.
See our full air purifier roundup for mid-range and premium options, or our breakdown of whether air purifiers are worth buying at all if you're still on the fence.