How often should you replace your air purifier filter?

Replace the main HEPA filter every 6 to 12 months for most air purifiers: 17 of the 20 best-selling purifiers below say so, and 7 of them say once a year. Smoke, pets and running it all day wear a filter out sooner.

By Erin Rose · Updated

01 / Your model

Find your purifier: the filter, how often, and the cost a year

Genuine replacement filter, maker schedule, price and cost per year for 20 air purifiers
Purifier and its genuine filterChange everyPricePer yearBuy
Levoit
Levoit Core 300 / 300SGenuine Core 300-P-RF filter 6 to 8 months[2]The best-selling off-brand filter saves about $21 a year. $25.99 $44.55 Buy
Levoit Core MiniGenuine Core Mini-P filter 4 to 6 months[3] $22.49 $53.98 Buy
Levoit Core 200SGenuine Core 200S-RF filter 6 to 8 months[4]The best-selling off-brand filter saves about $22 a year. $25.98 $44.54 Buy
Levoit Vital 100SGenuine Vital 100S-P filter About 9 months[5]Levoit's Amazon listing says 6 to 12 months. The middle of that is also 9. $39.47 $52.63 Buy
Levoit Vital 200SGenuine Vital 200S-P filter 6 to 12 months[6]Levoit's filter page says 6 to 12 months; the Vital 200S-P manual says 12. We price it at the middle, 9 months. $49.99 $66.65 Buy
Off-brand option JORAIR Vital 200S filter, 2‑packSaves about $39 a year. No lab test of it found; see our off-brand check. Same as genuine (assumed) $40.992 filters $27.33 Buy
Levoit Core 400SGenuine Core 400S-P filter 12 months[7] $49.98 $49.98 Buy
Levoit Core 600SGenuine Core 600S-P filter 6 to 12 months[8] $59.99 $79.99 Buy
Coway
Coway Airmega AP-1512HH (Mighty)Genuine filter set: 1 HEPA + 2 carbon HEPA 1 year, carbon 6 months[9]The best-selling off-brand filter saves about $28 a year. $44.99 $44.99 Buy
Coway Airmega 400 / 400SGenuine Max2 filter set (2 filters, one change) 12 months[10] $99.00 $99.00 Buy
GermGuardian
GermGuardian AC4825Genuine Filter B (FLT4825) 6 months[11]GermGuardian also suggests a carbon pre-filter (FLT22CB4) every 2 to 3 months, sold separately. It is not in the cost a year. The best-selling off-brand filter saves about $25 a year. $19.88 $39.76 Buy
Winix
Winix 5500-2Genuine Filter H (116130) 12 months[12]The best-selling off-brand filter saves about $13 a year. $27.81 $27.81 Buy
Winix 5300-2, C535 and AM90Genuine Filter A (115115) HEPA 12 months, carbon 3 months[13] $35.97 $35.97 Buy
Winix C545Genuine Filter S (1712-0096-00) HEPA 12 months, carbon 3 months[14] $49.99 $49.99 Buy
Blueair
Blueair Blue Pure 211+Genuine 211+ Particle + Carbon filter (not for the 211+ Auto) About 6 months[15] $68.39 $136.78 Buy
Blueair Blue Pure 211i MaxGenuine 211i Max filter Up to 9 months[16] $69.99 $93.32 Buy
Blueair Blue Pure 311i MaxGenuine F3MAX filter Up to 9 months[17] $44.99 $59.99 Buy
Honeywell
Honeywell HPA300Genuine kit: 3 HEPA R + 4 pre-filter A (HRF-ARVP300) HEPA (R) 12 months, pre-filter (A) 3 months[18] $79.99 $79.99 Buy
Off-brand option Smilyan HPA300 filters, 6 HEPA (R) + 8 pre-filters (A)Saves about $56 a year. No lab test of it found; see our off-brand check. Same as genuine (assumed) $46.996 R + 8 A (two years) $23.50 Buy
Shark
Shark HP100 / HP102Genuine HE1FKPET filter 6 to 12 months[19] $69.99 $93.32 Buy
PuroAir
PuroAir 240Genuine PuroAir 240 filter Every 90 days[20] $74.992 filters $149.98 Buy
Medify
Medify MA-40Genuine MA-40 filter About 4 months (3,000 hours)[21] $40.17 $120.51 Buy

Each row above is the genuine filter. "Change every" is the maker's own schedule. "Per year" is its cost on that schedule at today's price.[1]

How we work out cost per year: the pack price, divided by the filters in the pack, times the filters you use a year. Filters a year = 12 ÷ the middle of the maker's schedule. For a Levoit Core 300 that is 12 ÷ 7 months, so $25.99 × 12 ÷ 7 = $44.55.

Where an off-brand filter saves $35 a year or more, a second row shows the best-selling off-brand option. We found no lab test of any of them. Read our off-brand check before you switch.

Prices are Amazon's on November 4, 2026, read from each product page that day. A Coway Mighty set is 1 HEPA filter and 2 carbon filters, one year of filters. A Honeywell HPA300 kit is 3 HEPA R filters and 4 carbon pre-filters, one year of filters. A Winix Filter A set is 1 HEPA filter and 4 carbon filters. Where a maker gives a range, we price the middle. Where it says "up to", we price that number.

Key takeaways

  • Pre-filters and separate carbon filters run on their own clock: clean the pre-filter every 2 to 4 weeks, and replace a separate carbon filter every 3 to 6 months.
  • Makers say every 3 to 12 months, depending on the purifier. Each schedule in the table is quoted from the maker's own page or manual.
  • At November 4, 2026 prices, genuine filters cost $27.81 a year (Winix 5500-2) to $149.98 a year (PuroAir 240) on the maker's schedule.
  • The filter light on most purifiers counts hours of use. It does not test the filter. Levoit, Honeywell and Medify say so in their manuals.
  • Smoke, dust, pets, cooking grease and running it all day wear a filter out sooner. Check the filter more often then.

02 / The light

How to tell it's time: the filter light is a reminder, not a test

On most purifiers, the filter light counts how long the purifier has run. It does not look at the filter. Here is what each maker says.

  1. Levoit. The Check Filter light turns on "based on how much the air purifier has been used." Run it a lot and it comes on sooner. Run it a little and it comes on later. Levoit says to check the filter when the light comes on; you may not need a new one yet.[22]
  2. Honeywell. The HPA300 has two filter lights. They remind you "based on the air cleaner's hours of use."[18]
  3. Medify. When you reset the MA-40 light, "the timer will be reset for 3000 hours."[23]
  4. Blueair. Blueair works out filter life from fan speed, hours of use and pollution levels. On the 211+, a red light comes on after about 6 months.[15]
  5. Coway. The Mighty schedule assumes 8 hours a day on the top fan speed. The manual says the right time "may differ depending on the operating environment."[24]
  6. Winix. Replace the filters even if the light is not on when they are heavily soiled, smell bad, or the fan is much weaker.[25]

So use the light as a reminder to look. Pull the filter out. If it is caked with dust, smells, or the purifier blows much less air than it used to, change it.

03 / Sooner

What wears a filter out sooner

The makers' schedules are for normal use. These things shorten them.

  1. Smoke, dust and pets. Honeywell: "High concentrations of contaminates such as dust, pet dander and smoking will reduce the useful performance of the filter."[18]
  2. Running it a lot. Levoit: "If you run your air purifier frequently, [the light] will turn on sooner."[7]
  3. Wildfire season and remodeling. PuroAir: "More frequent replacements may be necessary during increased pollution, such as wildfire season or significant renovations."[20]
  4. Dusty homes. Winix: "The more dust present in the environment, the more dust accumulates in the filters, shortening the life."[25]
  5. Cooking grease. Medify says not to run the MA-40 where oil or grease is being cooked, because it "may clog the filters."[23]
  6. Damp rooms. Levoit says moisture may damage the Core Mini filter, and to use it where humidity is below 85%.[3]

A clean pre-filter helps. Levoit says to clean it every 2 to 4 weeks with a soft brush or vacuum. Winix says every 14 days. Coway says every 2 to 4 weeks.

04 / Reset

How to reset the filter light

The light stays on until you reset it, even with a new filter in. These are the steps from each maker we read.

How to reset the filter light, by brand
BrandHow to reset the filter light
Levoit (Core 300, 200S, 400S, 600S, Vital)With the purifier on, press and hold the filter button for 3 seconds until the light goes off.[22]
Levoit Core MiniPlugged in with the fan off, press and hold the Control Button for 3 seconds. The light blinks 3 times and goes off.[3]
Coway MightyAfter you put in the new filter, hold the Reset button for 2 seconds.[24]
Coway Airmega 400Touch and hold the Max2 Change button for 2 to 3 seconds.[26]
Winix 5500-2 and C545With the purifier on, hold the Filter Reset button for at least 5 seconds until it beeps.[27]
Honeywell HPA300With the purifier on, press and hold the lit button for about 2 seconds until the light goes off.[18]
Blueair 211+Press and hold the center button until the red light goes off. It usually takes 7 to 10 seconds.[15]
Blueair 211i Max and 311i MaxHold the fan speed button for about 15 seconds, until all the lights come on, then let go.[16]
Medify MA-40With the new filter in and the purifier on, hold Fan Speed and Ionizer together for 3 to 5 seconds.[23]

05 / Off-brand

Genuine or off-brand filter?

Our off-brand check found no lab test of the best-selling off-brand filters for these purifiers. For a Levoit Core 300, buy the genuine filter: switching saves only about $21 a year. Off-brand makes more sense where it saves more: about $56 a year on a Honeywell HPA300 and $39 on a Levoit Vital 200S.

One more reason to stay genuine on a Levoit: Levoit says its filter-life light "only works with authentic filters," so with an off-brand filter the reminder may come late.

Are off-brand air purifier filters as good? Our cost and test check

06 / Questions

Frequently asked

How often should I replace my air purifier filter?
Every 6 to 12 months for most purifiers, but follow your maker: Levoit Core 300, 6 to 8 months; Coway Mighty, 1 year for the HEPA filter; Winix, 12 months; Blueair 211+, about 6 months; PuroAir 240, every 90 days. Sooner with smoke, pets or 24-hour use.
Does the filter light mean my filter is dirty?
No, not on most purifiers. Levoit, Honeywell and Medify say their light runs on hours of use. Check the filter when the light comes on, and change it sooner if your air is smoky or dusty.
Can I wash my air purifier filter?
Not the HEPA filter. Honeywell says none of its filters are washable, Winix says its True HEPA filter cannot be washed, and Medify says not to vacuum or wash its filter. You can clean most pre-filters: Levoit says every 2 to 4 weeks, Winix every 14 days.
How often should I change the carbon filter?
Where it is a separate filter: the Coway Mighty's carbon filters every 6 months, Winix Filter A and Filter S carbon every 3 months, and Honeywell's A pre-filter every 3 months. The Winix 5500-2 carbon filter is washed every 3 months and replaced with the HEPA filter once a year. On Levoit, Blueair 211+, Medify and PuroAir filters the carbon is part of the main filter, so it is changed with it.
What happens if I do not change the filter?
The purifier cleans less air. Blueair says "dirty filters clean the air less efficiently," and Winix says a much weaker fan is a sign to replace the filter.
Why is the filter light still on after I changed the filter?
The light does not know you changed the filter. You have to reset it, usually by holding one button for 2 to 15 seconds. See the reset steps for your brand above.

References

Sources

27 references · prices on November 4, 2026
  1. 1

    Amazon listings: each genuine filter, its pack and price

    22 listings. Price and seller read from each Amazon product page on November 4, 2026. Which purifiers: the filters with the biggest "bought in past month" badges on Amazon's "air purifier replacement filter" searches, read October 22, 2026.

  2. 2

    Levoit: Core 300-P replacement filter

    Read October 22, 2026. "We recommend replacing your filters every 6 to 8 months." Part Core 300-P-RF.

  3. 3

    Levoit Core Mini-P air purifier user manual

    Read October 23, 2026. "The filter should be replaced every 4-6 months." The Check Filter light turns on "depending on how often you use the air purifier". Reset: fan off, hold the Control Button 3 seconds.

  4. 4

    Levoit: Core 200S-P replacement filter

    Read October 22, 2026. "It is recommended to replace filters for every 6-8 months." Part Core 200S-RF.

  5. 5

    Levoit Vital 100S-P smart air purifier user manual

    Read October 23, 2026. "The Main / Activated Carbon Filter should be replaced approximately every 9 months." The light "will light up based on how much the air purifier has been used".

  6. 6

    Levoit: Vital 200S-P replacement filter

    Read October 22, 2026. "Designed to last 6–12 months." The Vital 200S-P manual (levoit.com) says 12 months, and to clean the pre-filter every 2–4 weeks.

  7. 7

    Levoit Core 400S-P smart air purifier user manual

    Read October 23, 2026. "The filter should be replaced every 12 months." "If you run your air purifier frequently, [the light] will turn on sooner."

  8. 8

    Levoit Core 600S-P smart air purifier user manual

    Read October 23, 2026. "The filter should be replaced every 6-12 months." The light should turn on after about 6-12 months "if you use the air purifier consistently (24 hours of daily use)".

  9. 9

    Coway: Airmega 200M and AP-1512HH filter set

    Read October 22, 2026. 1 HEPA filter and 2 deodorization filters. "Custom Filter (6 Months), HEPA (1 Year)."

  10. 10

    Coway: Airmega 400/400S Max2 filter set

    Read October 23, 2026. "Max2 Filter Set (HEPA filter & activated carbon filter). Filter Life Expectancy is 12 Months."

  11. 11

    GermGuardian: FLT4825 Filter B (Smoke Clear) product page

    Read October 22, 2026. "Replacing one single combination filter every 6 months"; carbon FLT22CB4 every 2-3 months.

  12. 12

    Winix: Filter H (116130)

    Read October 22, 2026. A complete one-year set; change the HEPA and carbon filter once every 12 months.

  13. 13

    Winix: Filter A (115115)

    Read October 23, 2026. Fits the 5300-2, C535, AM90, 6300-2, P300 and others. "Change the True HEPA Filter once every 12 months and the Carbon Filter once every 3 months."

  14. 14

    Winix: Filter S (1712-0096-00)

    Read October 23, 2026. Fits the C545. True HEPA filter once every 12 months, carbon filter once every 3 months.

  15. 15

    Blueair: Blue Pure 211+ Particle + Carbon filter

    Read October 23, 2026. Red light "after about 6 months of operation". Reset: "press the center button down ... It usually takes 7-10 seconds." Not for the 211+ Auto. Filter life is worked out "based on fan speed, usage time and pollution levels".

  16. 16

    Blueair: Blue Pure 211i Max filter

    Read October 23, 2026. "Depending on usage, your filter will last up to 9 months." Reset: hold the fan speed button about 15 seconds.

  17. 17

    Blueair: replacement filter for the Blue Pure 311i Max (SmokeBlock version page)

    Read October 23, 2026. "Depending on usage, your filter will last up to 9 months." Fits only the Blue Pure 311i Max.

  18. 18

    Honeywell HPA090/100/200/300 owner's manual

    Read October 22, 2026. HPA300 uses 3 HEPA R filters; HEPA every 12 months, pre-filter every 3 months; "None of the filters are washable."

  19. 19

    SharkNinja: HE1FKPET anti-allergen filter with true HEPA

    Read October 23, 2026. Fits HP100, HP102, HP105 and the HC450 series. "Replace filter every 6 to 12 months."

  20. 20

    PuroAir: 240 replacement filter

    Read October 23, 2026. "Replace every 90 days for optimal air quality." "More frequent replacements may be necessary during increased pollution, such as wildfire season or significant renovations."

  21. 21

    Medify Air: MA-40 replacement filter

    Read October 23, 2026. "MA-40 filters should be replaced after 3,000 hours or about four months of use." The MA-40 manual: hold Fan Speed and Ionizer 3-5 seconds and "the timer will be reset for 3000 hours".

  22. 22

    Levoit Core 300-P air purifier user manual

    Read October 23, 2026. The Check Filter light "will light up based on how much the air purifier has been used". "Using your air purifier in an environment with relatively high pollution may mean you will need to replace the filter more often, even if [the light] is off."

  23. 23

    Medify MA-40 user manual

    Read October 23, 2026 (a copy of Medify's manual hosted by Lafayette College). Reset: hold Fan Speed and Ionizer for 3-5 seconds; "the timer will be reset for 3000 hours." "DO NOT use air purifier in a room where oils or grease are being cooked with; that may clog the filters."

  24. 24

    Coway Airmega AP-1512HH user manual

    Read October 23, 2026. Deodorization filter every 6 months, HEPA filter every 1 year, pre-filter cleaned every 2-4 weeks. "Each service life is based on 8-hour use in maximum air speed. The recommended filter replacement cycles may differ depending on the operating environment." Reset: hold Reset 2 seconds.

  25. 25

    Winix 5300-2 user manual

    Read October 23, 2026 (Winix's manual, hosted by a retailer). "The more dust present in the environment, the more dust accumulates in the filters, shortening the life." "Replace filters even if the Change Filter indicator has not yet turned on" when they are heavily soiled, smell bad or the fan is much weaker.

  26. 26

    Coway Airmega 300/400 (S) user manual

    Read October 23, 2026. "After replacing the Max2 filters, touch and hold this button for 2~3 seconds to reset the indicator."

  27. 27

    Winix 5500-2 user manual

    Read October 23, 2026. Pre-filter: "Clean once every 14 days". Carbon filter: clean once every 3 months; True HEPA lasts about 12 months. Reset: "hold the Filter Reset Button for at least 5 seconds until you hear the beep."

How we check numbers: our methodology.