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Filters › Blueair Blue Signature (Medium)
Blueair Blue Signature (Medium) replacement filter
The Blueair Blue Signature (Medium) takes the Blue Signature Medium Filter. It costs $69.99 at Blueair's store and lasts up to 12 months, which works out to about $70 a year in filters.
The numbers
| Filter | Blue Signature Medium Filter |
|---|---|
| Price at Blueair's store | $69.99 |
| Lasts | up to 12 months |
| Filters per year | $70 |
| Electricity per year (est.) | $21 |
| Total running cost per year (est.) | $91 |
| Five years of filters | $350, against $300 for the purifier |
Filter price and replacement schedule are Blueair's own, checked 2026-10-01. Yearly figures are our calculation from them; electricity assumes 24/7 use at a typical fan speed and $0.17/kWh.
How it compares
Its yearly filter cost ranks 10 of 23 purifiers we track (1 is cheapest). Against other purifiers for large rooms:
| Purifier | Filter | Per year |
|---|---|---|
| Blueair Blue Pure 311i+ Max | $49.99 | $67 |
| Blueair Blue Signature (Medium) | $69.99 | $70 |
| Blueair Blue Pure 211i Max | $69.99 | $93 |
| Blueair Blue Signature (Large) | $99.99 | $100 |
| Levoit Core 600S-P | $59.99 | $120 |
| Coway Airmega 400 | $129 | $129 |
| Levoit EverestAir-P | $99.99 | $200 |
Other filters Blueair sells for the Blue Signature (Medium)
Besides the standard filter, Blueair lists this for the Blue Signature (Medium). The type is Blueair's own description of what the filter is for; we have not tested any of them, and the purifier's published CADR is for its standard filter.
| Type | Filter | Price | vs. standard | Why it's listed for this purifier | |
|---|---|---|---|---|---|
| Pre-filter | Blueair Blue Signature™ Medium Pre-Filter | $22.99 checked 2026-10-11 | — | Blueair's listing names it: “Blue Signature™ Medium Pre-Filter” (source, confirmed 2026-10-11) |
Prices are from Blueair's store. The yearly cost above uses the standard filter; a dearer filter replaced on the same schedule raises it in proportion. A pre-filter is the outer layer that catches hair and large dust before the main filter.
When to replace it
- Follow the purifier's filter indicator rather than the calendar: it tracks actual use, and the brand's schedule is a maximum under normal conditions.
- Wildfire smoke, heavy cooking, pets and dusty rooms shorten a filter's life. A filter that looks grey or carries a smell is due even if the light hasn't come on.
- Third-party filters are cheaper, but the brand's performance figures only apply with its own filter, and on some purifiers the filter-life tracking only works with genuine ones.
See the full specs for the Blueair Blue Signature (Medium), the cheapest purifiers to run, or every purifier's filter cost.