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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. 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
  2. C1 Pentek Undersink Filter Replacement Cartridge

    C1 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 Retail Price:  $15.34
  3. ECP5-10 Pentek Undersink Filter Replacement Cartridge

    ECP5-10 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
    $8.99 Retail Price:  $9.42
  4. RS2-SS OmniFilter Whole House Filter Replacement Cartridge

    RS2-SS OmniFilter Whole House Water Filter Cartridge

    Fits any brand of whole house water filter system that uses standard 9 3/4 x 2 1/2 filter cartridges Learn More
    $7.99 Retail Price:  $8.04
  5. TO1SS OmniFilter Whole House Filter Replacement Cartridge

    TO1SS OmniFilter Whole House Water Filter Replacement Cartridge

    Designed to fit into any brand of whole house water filtration system that accepts standard 9 3/4 x 2 1/2 inch cartridges Learn More
    $12.99 Retail Price:  $15.34
  6. WHEEDF Whirlpool UltraEase Water Filter Pack

    WHEEDF Whirlpool UltraEase Water Filter Pack

    Fits the WHED20 Whirlpool dual stage drinking water filtration system Learn More
    $47.99 Retail Price:  $59.79
  7. CQE-RC-04000 Crystal Quest Carbon Block Water Filter Cartridge

    CQE-RC-04000 Crystal Quest Carbon Block Water Filter Cartridge

    Fits Crystal Quest countertop, undersink and refrigerator water filtration systems Learn More
    $23.99 Retail Price:  $28.74
  8. RS4-DS OmniFilter Whole House Filter Replacement Cartridge (2-Pack)

    RS4-DS OmniFilter Whole House Filter Replacement Cartridge (2-Pack)

    Fits any brand of whole house water filter system that uses standard 9 3/4 x 2 1/2 filter cartridges Learn More
  9. D-15 Culligan Level 1 Undersink Filter Replacement Cartridge (2-Pack)

    D-15 Culligan Level 1 Undersink Filter Replacement Cartridge (2-Pack)

    Fits Culligan US-550, US-600, US-600A, RO-3000, RO-3500, RVF-10 and any brand of water filtration system that uses standard 9 3/4 x 2 1/2 filter cartridges Learn More
    $18.99 Retail Price:  $25.29
  10. D-10-TWIN Culligan Level 1 Undersink Filter Replacement Cartridge (2-Pack)

    D-10A Culligan Level 1 Undersink Filter Replacement Cartridge (2-Pack)

    Fits Culligan US-550, US-600, US-600A, SY-2000, SY-2100, and any brand of water filtration system that uses standard 9 3/4 x 2 1/2 filter cartridges Learn More
    $13.99 Retail Price:  $17.93
  11. W5CIP American Plumber Undersink Filter Replacement Cartridge (2-Pack)

    W5CIP American Plumber Undersink Filter Replacement Cartridge (2-Pack)

    Fits American Plumber W38-PR and most standard size water filter housings Learn More
    $21.99 Retail Price:  $24.34
  12. PD-5-934 Pentek Undersink Filter Replacement Cartridge

    PD-5-934 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
    $9.99 Retail Price:  $12.34
  13. RWC-5 Culligan Level 1 Undersink Filter Replacement Cartridge

    RWC-5 Culligan Level 1 Undersink Filter Replacement Cartridge

    Fits Culligan Fulflo, WC12, LCA, WS-12, and any brand of water filter system that uses standard 9 3/4 x 2 1/2 filter cartridges Learn More
    $12.99 Retail Price:  $17.24
  14. P5-D Culligan Level 4 Whole House Filter Replacement Cartridge (2-Pack)

    P5-D Culligan Level 4 Whole House Filter Replacement Cartridge (2-Pack)

    Fits Culligan HF-150, HF-160, HF-360, HF-365, and any brand of whole house water filter system that uses standard 9 3/4 x 2 1/2 filter cartridges Learn More
    $12.99 Retail Price:  $15.34
  15. NCP-10 Culligan Whole House Filter Replacement Cartridge

    NCP-10 Culligan Whole House Filter Replacement Cartridge

    Fits any brand of whole house water filter system that uses standard 9 3/4 x 2 1/2 filter cartridges Learn More

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