How Often to Replace Your Air Purifier Filter: UK Guide (2026)
Updated: October 2026 · filter replacement timing · Prices checked 18 Oct 2026
Filter costs by model — UK verified stock
The table below is generated from our verified product data. Filter cost per year is calculated as: filter price × (12 ÷ replacement interval in months). This is the number that matters for budgeting — not the one-off filter price.
| Model | Filter price | Interval (months) | Filter cost/yr | UK stock note |
|---|---|---|---|---|
| Levoit Core 300S | £19.99 | 6 | £39.98 | Available Amazon UK + Levoit UK |
| Levoit Core 400S | £24.99 | 6 | £49.98 | Available Amazon UK + Levoit UK |
| Levoit Core 200S | £14.99 | 6 | £29.98 | Available Amazon UK + Levoit UK |
| Coway Airmega Mighty (AP-1512HH) | £39.99 | 12 | £39.99 | Available Amazon UK (Awin filter route not available — see note above) |
| Coway Airmega 150 | £34.99 | 12 | £34.99 | Available Amazon UK (Awin filter route not available — see note above) |
| Blueair Blue Max 3250i | £35.00 | 6 | £70.00 | Available Amazon UK + Blueair UK |
| Blueair Blue Pure 211i Max | £69.00 | 12 | £69.00 | Available Amazon UK + Blueair UK |
| Blueair Blue Pure Mini Max | £29.99 | 6 | £59.98 | Available Amazon UK + Blueair UK |
| Shark NeverChange5 HP072UK | £49.99 | 60 | £10.00 | Available Amazon UK (only source for UK) |
| Philips 600 Series AC0651 | £44.99 | 12 | £44.99 | Available Amazon UK + Philips UK |
| Philips 3200 AC3220/10 | £64.99 | 12 | £64.99 | Available Amazon UK + Philips UK |
| Philips 2200 Series AC2220/10 | £44.99 | 36 | £15.00 | Available Amazon UK + Philips UK |
| Meaco Arete Two | £39.99 | 12 | £39.99 | Meaco UK direct (best source) |
| Winix Zero S ⚠ | £69.99 | 12 | £69.99 | Winix Europe direct only — availability unconfirmed on Amazon UK |
| IQAir HealthPro 250 | £299.00 | 24 | £149.50 | IQAir UK direct only — £299 replacement filter |
⚠ Winix Zero S: Amazon UK availability unconfirmed — Winix Europe direct route only. Filter prices and intervals from manufacturer UK data; checked 18 Oct 2026.
The cost of running a dead filter
A clogged HEPA filter creates two costs simultaneously, and both are real even if neither is easy to put a precise number on:
- Higher electricity draw: a loaded filter increases resistance in the airflow path. The fan motor works harder to pull the same volume of air through — meaning wattage rises even though the air output drops. The relationship is not linear and varies by motor type, but the principle is consistent: higher resistance → higher wattage → higher bill. Manufacturers do not publish this curve for most consumer models.
- Reduced effective CADR: if airflow drops because the filter is restricting the fan, the volume of clean air delivered per hour (the CADR figure) also falls. A 300S running at reduced airflow through a loaded filter does not deliver 246 m³/h — it delivers less. The room-cleaning time extends, and the 3 ACH target you sized the unit to is no longer met.
Honest note: both effects are hard to quantify without access to specific test data for each model at each filter-loading stage. What the data does support is the principle: a loaded filter degrades both efficiency and effectiveness. The manufacturer's replacement interval exists for a reason. Running past it costs you more than the filter price you saved.
The exception is the Shark NeverChange5 with its 5-year filter claim. We discuss this directly in our Shark review — the short version: the claim holds under light use but is contested under heavy use in user data. See the three-scenario breakdown there.
When to replace vs when to clean
Most multi-stage filters include a pre-filter — a coarser layer that catches larger particles (pet hair, dust, fibres) before they reach the HEPA. The pre-filter is the one you should clean regularly; the HEPA layer is the one you replace.
- Levoit Core series: pre-filter is part of the combined filter unit — not separately washable. Replace the whole unit at the stated interval.
- Coway Airmega Mighty & 150: washable pre-filter included. Clean monthly; vacuum gently or rinse under cold water, let dry fully before reinstalling.
- Blueair models: fabric pre-filter on some models (Blue Pure range) — machine washable. Replace the particle + carbon filter every 6 months regardless.
- Philips models: pre-filter layer is integrated into the main filter cassette — not separately washable on the 600 or 3200 series.
- Meaco Arete Two: pre-filter is washable; Meaco recommends cleaning every 2 weeks during heavy use (damp season).
The rule: clean the pre-filter often (monthly in most homes, more often during high-particulate periods). Replace the HEPA+carbon unit on the manufacturer's schedule or earlier if you notice reduced airflow, increased noise, or a persistent odour that was not there before.
UK-specific note on timing: UK air quality peaks in late autumn (wood-burning stoves, bonfire night) and in spring (pollen, Saharan dust events). If your filter indicator triggers just before or during these peaks, replace it — do not wait. Running a near-saturated filter into a high-particulate period defeats the purpose.
Commercial routing — why Coway filters go to Amazon UK
This site uses Awin affiliate links for Levoit, Meaco, and Coway units. For Coway replacement filters, the situation is different: Coway's Awin programme pays commission on unit sales but does not pay commission on replacement filter purchases.
Rather than link to a Coway filter page that earns us nothing and hide this from you, we route Coway filter links to Amazon UK — which does pay Amazon Associates commission on filter sales. Amazon UK stocks both the Airmega Mighty filter and the Airmega 150 filter, and the prices are comparable to buying direct.
We say this openly: the routing decision is commercial, not editorial. If you prefer to buy Coway filters direct from Coway UK, the option exists — we are just not incentivised to link there. This note applies only to replacement filters; Coway unit purchase links on this site go through Awin as normal.
Related guides
- Air purifier running costs UK — filter cost as a % of total running cost for all 13 models
- Levoit Core 300S review — filter ecosystem notes
- Levoit Core 400S review
- Coway Airmega Mighty review
- Coway Airmega 150 review
- Blueair Blue Max 3250i review
- Meaco Arete Two review
Filter prices and intervals from manufacturer UK data; stock availability checked 18 October 2026. Affiliate disclosure: this page contains Awin and Amazon UK affiliate links. Coway filter routing note disclosed above. Full affiliate disclosure.