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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. TO6 OmniFilter Whole House Filter Replacement Cartridge

    TO6-SS2-S06 OmniFilter Whole House Water Filter Replacement Cartridge

    Fits into any brand of whole house water filtration system that accepts filter cartridges sized 9 3/4 x 4 1/2 inches Learn More
    $22.99 Retail Price:  $24.14
  2. QC10-EPR Pentek Undersink Quick-Change Replacement Filter Cartridge

    QC10-EPR Pentek Quick-Change Replacement Water Filter Cartridge

    Fits any Pentek Quick-Change Series water filtration system heads Learn More
    $23.99 Retail Price:  $27.70
  3. CMB-520-HF Advanced Water Products 20-inch x 4.5-inch Replacement Sediment Filter

    Advanced Water Products CMB-520-HF Whole House Filter for IHS22-D4 System

    Made for the Trojan UV Max IHS22-D4 Water Disinfection System Learn More
  4. WFHDC8001 DuPont Universal Heavy Duty Carbon Wrap 2-Phase Cartridge

    WFHDC8001 DuPont Universal Heavy Duty Carbon Wrap 2-Phase Cartridge

    Fits WFHD13001B Universal Heavy Duty Whole House Filtration System and other brands of 10x4.5-inch filter systems Learn More
    $22.99 Retail Price:  $32.92
  5. CQE-RC-04015 Crystal Quest Reusable Pleated Water Filter

    CQE-RC-04015 Crystal Quest Reusable Pleated Water Filter

    Fits Crystal Quest countertop, undersink and refrigerator water filtration systems Learn More
    $21.99 Retail Price:  $32.19
  6. 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
  7. 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
  8. P1012581 Culligan Undersink Replacement Filter Cartridge

    P1012581 Culligan Undersink Replacement Filter Cartridge

    Fits the Culligan 201 Under Sink Water Filter System Learn More
  9. 3US-AF01 Filtrete Undersink Filter Replacement Cartridge

    3US-AF01 Filtrete Undersink Filter Replacement Cartridge

    Fits Filtrete 3US-AS01, 3US-PS01, and Whirlpool WHCF-SUF, WHCF-SUFC water filter systems Learn More
    $25.99 Retail Price:  $26.44

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