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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. EP-5 Pentek Replacement Filter Cartridge

    EP-5 Pentek Replacement Filter Cartridge

    Fits most housings that accept standard 5-inch x 2.5-inch water filter cartridges Learn More
  2. 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
    $9.99 Retail Price:  $20.34
  3. 3MFF101 Aqua-Pure Replacement Water Filter Cartridge

    3MFF101 Aqua-Pure Replacement Water Filter Cartridge

    Fits the Aqua-Pure 3MFF100 Full Flow drinking water system Learn More
    $200.99 Retail Price:  $209.29
  4. C-CS-FF Aqua-Pure Undersink Filter Replacement Cartridge

    C-CS-FF Aqua-Pure Undersink Water Filter Cartridge

    Fits the Aqua-Pure Easy Full Flow Drinking Water Filtration System Learn More
    $43.99 Retail Price:  $48.06
  5. 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
  6. AP517 Aqua-Pure Undersink Filter Replacement Cartridge

    AP517 Aqua-Pure Undersink Filter Replacement Cartridge

    Fits Aqua-Pure undersink water filter systems Learn More
    $68.99 Retail Price:  $70.14
  7. AP217 Aqua-Pure Undersink Filter Replacement Cartridge

    AP217 Aqua-Pure Undersink Filter Replacement Cartridge

    Fits Aqua-Pure undersink water filter systems Learn More
    $36.99
  8. GXULQR GE Undersink Water Filter Replacement Cartridge

    GXULQR GE Undersink Water Filter Replacement Cartridge

    Fits the GE GXULQ and GNULQ Systems Learn More
    $41.99 Retail Price:  $43.69
  9. GAC-20 Pentek Replacement Filter Cartridge

    GAC-20 Pentek Replacement Filter Cartridge

    Fits most housings that accept standard 20-inch x 2.5-inch water filter cartridges Learn More
    $21.99 Retail Price:  $23.56
  10. 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
  11. P5-478 Pentek Undersink Filter Replacement Cartridge

    P5-478 Pentek Undersink Filter Replacement Cartridge

    Fits any standard housing that uses 5-inch x 2 1/2-inch replacement filter cartridges Learn More
    $6.99 Retail Price:  $8.15
  12. GAC-BB Pentek Replacement Filter Cartridge

    GAC-BB Pentek Replacement Filter Cartridge

    Fits most Big Blue housings that accept 10-inch x 4.5-inch water filter cartridges Learn More
    $25.99 Retail Price:  $32.19
  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. 3US-PF01 Filtrete Undersink Filter Replacement Cartridge

    3US-PF01 Filtrete Undersink Filter Replacement Cartridge

    Fits Filtrete 3US-AS01, 3US-PS01, and Whirlpool WHCF-SUF, WHCF-SUFC water filter systems Learn More
    $39.99 Retail Price:  $43.69
  15. 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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