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Replacement Water Filters: Undersink

Don’t settle for a replacement under sink water filter cartridge that simply fits, find one designed and manufactured specifically for your under sink water filter system.

Discount Filter Store has one of the largest selections of undersink filter cartridges. With under sink filter cartridges available in over 15+ different filter medias, 8+ different sizes (5x2½ - 20x4½), and a wide variety of filter life’s ranging from 250 gallons to 50,000+ gallons, you’re guaranteed to find the under sink water filter system and/or replacement cartridges you need. Choose from hundreds of under sink water filter cartridges from some of the industry’s top brands including American Plumber, Crystal Quest, Pentek®, Culligan®, GE, Aqua-Pure®, Whirlpool®, and more.

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  1. 32-250-125-050 KX Technologies Replacement Filter Cartridge

    32-250-125-050 KX Technologies Replacement Filter Cartridge

    Fits most standard housings that accept 5-inch filters Learn More
    $10.99
  2. MATRIKX-Pb1-10 KX Technologies MatrikX Undersink Filter Replacement Cartridge

    MATRIKX-Pb1-10 KX Technologies MatrikX Undersink Filter Replacement Cartridge

    Fits any standard housing that uses 9 3/4-inch x 2 1/2-inch replacement filter cartridges Learn More
    $19.99 Retail Price:  $22.34
  3. MATRIKX-CTO2-10 KX Technologies MatrikX Undersink Filter Replacement Cartridge

    MATRIKX-CTO2-10 KX Technologies MatrikX Undersink Filter Replacement Cartridge

    Fits any standard housing that uses 9 3/4-inch x 2 1/2-inch replacement filter cartridges Learn More
    $12.99
  4. MATRIKX-1-10 KX Technologies MatrikX Undersink Filter Replacement Cartridge

    MATRIKX-1-10 KX Technologies MatrikX Undersink Filter Replacement Cartridge

    Fits any standard housing that uses 9 3/4-inch x 2 1/2-inch replacement filter cartridges Learn More
    $18.99
  5. CC-10 Pentek Undersink Filter Replacement Cartridge

    CC-10 Pentek Undersink Filter Replacement Cartridge

    Fits any standard housing that uses 9 3/4-inch x 2 1/2-inch replacement filter cartridges Learn More
    $14.99 Retail Price:  $15.34
  6. CBR2-10R Pentek Undersink Filter Replacement Cartridge

    CBR2-10R Pentek Undersink Filter Replacement Cartridge

    Fits Pentek under-sink filter housings and any housing that uses standard 9 3/4-inch by 2 1/2-inch filter cartridges Learn More
    $18.99 Retail Price:  $21.95
  7. CBR2-10 Pentek Undersink Filter Replacement Cartridge

    CBR2-10 Pentek Undersink Filter Replacement Cartridge

    Fits any standard housing that uses 9 3/4-inch x 2 1/2-inch replacement filter cartridges Learn More
    $18.99
  8. QC10-TSGACR Pentek Undersink Quick-Change Replacement Filter Cartridge

    QC10-TSGACR Pentek Quick-Change Replacement Water Filter Cartridge

    Fits any Pentek Quick-Change Series water filtration system head Learn More
    $19.99 Retail Price:  $21.84
  9. QC10-GACR Pentek Undersink Quick-Change Replacement Filter Cartridge

    QC10-GACR Pentek Quick-Change Replacement Water Filter

    Fits any Pentek Quick-Change Series of water filtration system heads Learn More
    $18.99 Retail Price:  $20.57
  10. Whirlpool WHKF-GAC Undersink Replacement Water Filter Cartridge

    WHKF-GAC Whirlpool Undersink Replacement Filter Cartridge

    Fits the Whirlpool WHKF-DUF Under Sink Filter Housing Learn More
    $10.99 Retail Price:  $20.34
  11. D-25 Culligan Under Sink Water Filter

    D-25 Culligan Under Sink Water Filter

    Fits under sink filter systems that use 10 x 2.5-inch filters Learn More
    $11.99 Retail Price:  $16.99
  12. D-28 Culligan Level 1 Undersink Filter Replacement Cartridge

    D-28 Culligan Level 1 Undersink Filter Replacement Cartridge

    Fits Culligan US-550, US-600, US-600A, and any brand of water filter system that uses standard 9 3/4 x 2 1/2 filter cartridges Learn More
  13. D-20A Culligan Level 1 Undersink Water Filter Replacement Cartridge

    D-20A Culligan Level 1 Undersink Filter Replacement Cartridge

    Fits Culligan US-550, US-600, US-600A, RO-2127, RO-3000, RO-3500, and any brand of water filtration system that uses standard 9 3/4 x 2 1/2 filter cartridges Learn More
    $14.99
  14. 750R-D Culligan Level 1 Undersink RV and Marine Icemaker and Drinking Water Filter

    750R-D Culligan Level 1 Undersink RV and Marine Icemaker and Drinking Water Filter

    Fits Culligan SY-750s, RV-750, IC-750, SY-1000, SY-1000s, RV-1000, and IC-1000 filter systems Learn More
    $17.99
  15. WCC American Plumber Undersink Filter Replacement Cartridge

    WCC American Plumber Undersink Filter Replacement Cartridge

    Fits American Plumber W38-PR and most standard size water filter housings Learn More
    $19.99 Retail Price:  $26.44
  16. DW-200-R American Plumber Undersink Filter Replacement Cartridge

    DW-200-R American Plumber Undersink Filter Replacement Cartridge

    Fits Cuno AP-200 and PurWater PW-200 housings Learn More
    $18.99 Retail Price:  $21.15
  17. WGC478 American Plumber Undersink Compact Filter Replacement Cartridge

    WGC478 American Plumber Undersink Compact Filter Replacement Cartridge

    Fits American Plumber WGC478 Learn More
    $13.99 Retail Price:  $14.94
  18. GAC1SS OmniFilter Series C Undersink Filter Replacement Cartridge

    GAC1SS OmniFilter Undersink Water Filter Cartridge (Series C)

    Fits any brand of undersink water filtration system that accepts filter cartridges sized 9 3/4 x 2 1/2 Learn More
    $16.99
  19. GAC-10 Pentek Undersink Filter Replacement Cartridge

    GAC-10 Pentek Undersink Filter Replacement Cartridge

    Fits any standard housing that uses 9 3/4-inch x 2 1/2-inch replacement filter cartridges Learn More
    $12.99
  20. GAC-5 Pentek Replacement Filter Cartridge

    GAC-5 Pentek Replacement Filter Cartridge

    Fits most housings that accept standard 5-inch x 2.5-inch water filter cartridges Learn More
    $14.99

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