Best Air Purifier for Allergies and Hay Fever UK (2026)
Updated: October 2026 · Only UK-verified stock · Prices checked 18 Oct 2026
Most allergy guides rank purifiers on CADR alone. CADR tells you how fast a machine moves air through its filter — it does not tell you whether the filter actually captures the allergen that affects you. The two independent certification bodies for allergen capture in the UK market are Allergy UK (Allergy UK Seal) and ECARF (European Centre for Allergy Research Foundation). If a purifier holds one of these, a body outside the manufacturer has tested the allergen-capture claim. If it does not, you are relying on manufacturer specification only.
This page is structured around the pollen calendar as well as year-round allergens. Hay fever peaks differ by allergen type — tree pollen peaks in spring, grass pollen in early summer. The right time to buy (and to run the purifier at higher speed) follows that calendar.
Certification comparison
Certifications verified against UK product listings, October 2026. Where a certification is not held on the UK listing, it is stated as "No" — not omitted.
| Model | Allergy UK Seal | ECARF | EN 1822 H13 | CADR (m³/h) | Sleep (dB) | UK price |
|---|---|---|---|---|---|---|
| Coway Airmega Mighty (AP-1512HH) | Yes — Allergy UK Seal | No | Not tested | 408 converted from AHAM CFM 240 × 1.699 |
24dB | £219.99 |
| Coway Airmega 150 | No | Yes — ECARF Quality Seal | Not tested separately | 277 converted from AHAM CFM 163 × 1.699 |
20dB | £149.99 |
| Levoit Core 300S | No | No | Not tested (H13 manufacturer-claimed) | 246 converted from AHAM CFM 145 × 1.699 |
24dB | £84.99 |
| Blueair Blue Max 3250i | No | No | Not applicable — HEPASilent, not True HEPA | 239 manufacturer (m³/h) |
18dB | £129.00 |
Allergy UK Seal: confirmed on AP-1512HH UK listing. ECARF: confirmed on Airmega 150 UK listing — not confirmed on the Mighty AP-1512HH UK listing (a common misconception). Blueair HEPASilent is not True HEPA and is outside the scope of EN 1822 certification — performance is electrostatic + mechanical combined.
UK pollen calendar — when to run your purifier harder
| Pollen type | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Tree pollen (birch, alder, hazel) | – | 🟡 | 🟠 | 🔴 | 🟠 | – | – | – | – | – | – | – |
| Grass pollen (main hay fever cause) | – | – | – | – | 🟡 | 🔴 | 🔴 | 🟡 | – | – | – | – |
| Weed pollen (nettle, plantain) | – | – | – | – | – | 🟡 | 🟠 | 🟠 | 🟡 | – | – | – |
| Mould spores (Cladosporium) | – | – | – | – | 🟡 | 🟠 | 🔴 | 🔴 | 🟠 | 🟡 | – | – |
🔴 Peak · 🟠 High · 🟡 Low · – None. Source: UK Met Office pollen season ranges. Regional variation applies — Scotland typically 2–3 weeks later than southern England. Run your purifier at medium or high speed (not sleep/auto) during peak months.
Our picks for allergies
Coway Airmega Mighty (AP-1512HH)
The Allergy UK Seal is independently tested — it means the dander and allergen capture claim has been verified against Allergy UK's own methodology, not just stated by the manufacturer. For households where allergy certification is the deciding factor, this is the verified choice.
Affiliate link — disclosure. Price may differ from that shown.
Coway Airmega 150
ECARF is the European equivalent of Allergy UK's seal — independently tested for allergen reduction. At 20dB sleep mode and 18m² coverage at 3 ACH it is the better bedroom pick for allergy sufferers. Note: it is the Airmega 150, not the Mighty, that holds the ECARF certification on UK listings.
Affiliate link — disclosure. Price may differ from that shown.
Levoit Core 300S
No independent certification, but the HEPA filter is manufacturer-claimed H13 and the sleep noise at 24dB is quiet enough for overnight use. For smaller bedrooms (under 12m²) where budget matters, this is the starting point. Upgrade to a Coway if certification is required.
Affiliate link — disclosure. Price may differ from that shown.
Blueair Blue Max 3250i
HEPASilent technology is not True HEPA — electrostatic + mechanical filtration reaches HEPA-equivalent efficiency without a purely mechanical filter. No independent allergy certification. Included because it is exceptionally quiet at 18 dB, has a washable pre-filter, and covers 33 m² at 3 ACH. For certified performance, the Coway 150 (ECARF) is the recommendation.
Affiliate link — disclosure. Price may differ from that shown.
What the certifications mean
Allergy UK Seal
Allergy UK is a UK patient organisation. Their seal is awarded after product testing against a defined methodology — the purifier must demonstrate allergen reduction to a set standard. The seal applies to a specific SKU (the AP-1512HH on the UK listing); buying a different Coway model does not carry the same endorsement.
ECARF Quality Seal
ECARF (European Centre for Allergy Research Foundation) is a German non-profit. Their seal is awarded after clinical or laboratory testing. The Coway Airmega 150 holds this certification on its UK listing. The Coway Airmega Mighty (AP-1512HH) does not — a fact confirmed by checking the UK product listings directly.
EN 1822 H13 — filter classification, not product certification
EN 1822 classifies the filter medium, not the whole device. An H13-grade filter captures ≥99.95% of 0.3µm particles. No purifier in this comparison is EN 1822 certified at the product level. The Philips 3200 (in our dust guide) has a confirmed H13 EN 1822 filter classification — that is still a filter grade, not a product-level allergen certification.
For dust mite allergy specifically — including the difference between filtering dust mite allergen fragments vs. the mites themselves — see the dust guide. For asthma, see the asthma hub (Wave 3). For pets as an allergen source, the pets guide has the pre-filter and carbon data.
Prices checked 18 October 2026. UK-verified stock only. Certification status verified against UK product listings (Oct 2026) — manufacturer claims on non-UK listings are not treated as UK certification. Airmega 150 full review at /reviews/coway-airmega-150/ (Wave 2). Affiliate disclosure.