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smyc305 17.7K Views
Sep 1, 2026 1:33 PM

Costco Members: Winix C909 4-Stage Air Purifier

$160

$200

20% off
+ $5 S&Hat Costco Wholesale
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Deal Details
Costco Wholesale has for its Members: Winix C909 4-Stage Air Purifier w/ WiFi & PlasmaWave Technology (1022-0228-00) on sale for $159.99. Shipping is $4.99.

Thanks to Community Member smyc305 for sharing this deal.

Features:
  • AHAM Verified up to 500 sq. ft. Room Coverage
  • Energy Star & UL Certified
  • Ultra-Quiet on Slowest Speed (25 db)
  • Wi-Fi Enabled for Instant Monitoring and Control
  • 2-Year Filter Supply: Includes 2 True HEPA replacement filters and 8 Activated Carbon Filters

Editor's Notes

Written by powerfuldoppler | Staff
  • This price matches our previous Frontpage Deal
  • $40 manufacturer's savings is valid 9/1/26 through 9/30/26. While supplies last.
  • Limit 5 per member.
  • This product is rated 4.6 out of 5 stars based on 950 customer reviews.
  • If you don't have a Costco Warehouse Membership, you can sign-up here

Original Post

Written by smyc305
Community Notes
About the Poster
Deal Details
Community Notes
About the Poster
Costco Wholesale has for its Members: Winix C909 4-Stage Air Purifier w/ WiFi & PlasmaWave Technology (1022-0228-00) on sale for $159.99. Shipping is $4.99.

Thanks to Community Member smyc305 for sharing this deal.

Features:
  • AHAM Verified up to 500 sq. ft. Room Coverage
  • Energy Star & UL Certified
  • Ultra-Quiet on Slowest Speed (25 db)
  • Wi-Fi Enabled for Instant Monitoring and Control
  • 2-Year Filter Supply: Includes 2 True HEPA replacement filters and 8 Activated Carbon Filters

Editor's Notes

Written by powerfuldoppler | Staff
  • This price matches our previous Frontpage Deal
  • $40 manufacturer's savings is valid 9/1/26 through 9/30/26. While supplies last.
  • Limit 5 per member.
  • This product is rated 4.6 out of 5 stars based on 950 customer reviews.
  • If you don't have a Costco Warehouse Membership, you can sign-up here

Original Post

Written by smyc305

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Community Reviews

The Winix C909 is a high airflow air purifier that works well for dust, pollen, and allergy relief, with reports of fewer allergies, less rash irritation, and pre filters that quickly collect visible debris. It uses the standard A filter with a carbon sheet, and the Costco bundle includes an extra filter plus Costco backing. The PlasmaWave ionizer defaults on, so it has to be turned off manually if desired, and WiFi control needs a 2.4 gigahertz network with no spaces in the network name. A bearing issue has also been raised on other Winix models, so long term reliability may be worth watching.

Common Questions (5)

  • Yes. It moves a lot more air than the other two models mentioned and works well for keeping dust and pollen down when there is enough space for it. It is also described as one of the best air purifiers at this price.

  • Yes. The PlasmaWave ionizer defaults to on, so it has to be turned off manually each time if you do not want it running. The ozone output is described as very low, so accidental use is not considered a major concern.

  • At $159.99, it is more expensive than a refurbished C909 bought for $120, but this Costco version includes an extra filter and Costco backing. The same price has also been paid at Costco before, which suggests it is a normal sale price for this model.

  • It uses the standard A filter with a carbon sheet, not the fancier carbon pellets. That makes it a simpler filter setup than some higher-end Winix models.

  • It can, but it requires a 2.4 GHz Wi‑Fi network and the SSID cannot contain spaces. Control is otherwise through the buttons on the unit or the Winix app.

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37 Comments

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Sep 3, 2026 1:12 PM
962 Comments
Joined Jul 2016
thischrisSep 3, 2026 1:12 PM
962 Comments
This is one of the best out there especially this price. We keep it running on full blast 24/7.
Paid this exact price in 2023 from Costco. So at least Costco and Winix keeping it real for the customers.
Sep 3, 2026 1:16 PM
808 Comments
Joined Sep 2013
chucktaylurSep 3, 2026 1:16 PM
808 Comments
Any recommendations for off brand filters? How would I know if a filter truly hepa?
1
Sep 3, 2026 3:19 PM
1.2K Comments
Joined Feb 2007
dave388Sep 3, 2026 3:19 PM
1.2K Comments
So many winix have bearing issue. Avoiding this brand. I have it on 5500-2 and a month in to 5510
1
Sep 4, 2026 11:57 PM
567 Comments
Joined Mar 2008
BudarowSep 4, 2026 11:57 PM
567 Comments
Quote from ImagineNoReligion View quoted comment :
Air quality is like hypertension. By the time you notice a difference, you're toast. Remember that the CDC recommends only respirators and HEPA filters for wildfire smoke, which is projected to kill tens of thousands of Americans every year in the next three decades.
If anyone doesn't think they need a quality air purifier in their house, in your office, etc., go outside at night with a bright flashlight and hold it out in front of your face pointing skyward during any season ( e.g. winter, summer, etc.) and plainly see the vast amount of particulate wafting about. That crap doesn't stay just outside and your breathing it 24/7/365.
Last edited by Budarow September 4, 2026 at 05:02 PM.
Sep 10, 2026 1:31 PM
1.7K Comments
Joined Jul 2007
PuzzleFighterSep 10, 2026 1:31 PM
1.7K Comments
Anyone know how the IEF or how power efficient these are?
Sep 21, 2026 5:47 PM
1.4K Comments
Joined Feb 2007
alexta6Sep 21, 2026 5:47 PM
1.4K Comments
How does this compare to the C710 QA which is on sale for 99.99. I have two French bulldogs with short hair and odor from puppy urine
Sep 21, 2026 5:51 PM
809 Comments
Joined Jan 2010
mystiqueskillzSep 21, 2026 5:51 PM
809 Comments
How does this air purifier compare to the WINIX C710 that's on sale at Costco for $100?

https://www.costco.com/.product.4201032861.html

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