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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.

18 Item(s)

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  1. 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
  2. C2 Pentek Undersink Filter Replacement Cartridge

    C2 Pentek Undersink Filter Replacement Cartridge

    Fits in compact 5-inch water filter housings Learn More
    $7.99 Retail Price:  $8.84
  3. RS7-SS OmniFilter Whole House Filter Replacement Cartridge

    RS7-SS OmniFilter Whole House Water Filter Replacement Cartridge

    Fits any brand of whole house water filtration system that uses standard 9 3/4 x 2 1/2 filter cartridges Learn More
    $7.99 Retail Price:  $8.38
  4. RS3-SS OmniFilter Whole House Filter Replacement Cartridge

    RS3-SS OmniFilter Replacement 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
  5. 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
  6. RS14-SS OmniFilter Whole House Filter Replacement Cartridge

    RS14-SS OmniFilter Replacement Whole House Water Filter Cartridge

    Fits any brand of whole house water filter system that uses 9 3/4 x 2 1/2 water filter cartridges Learn More
    $6.99 Retail Price:  $9.34
  7. RS14-DS OmniFilter Whole House Filter Replacement Cartridge (2-Pack)

    RS14-DS OmniFilter Whole House Water Filter Cartridges (2-Pack)

    Fits any brand of whole house water filtration system that uses standard 9 3/4 x 2 1/2 filter cartridges Learn More
    $7.99 Retail Price:  $8.15
  8. 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
  9. 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
  10. C2-02 Advanced Water Products 20-inch x 4.5-inch Replacement Carbon Whole House Filter

    C2-02 Advanced Water Products Replacement 20-inch x 4.5-inch Carbon Whole House Filter

    Fits most 20-inch x 4.5-inch filter housings, including the Trojan UV Max IHS12-D4 and IHS22-D4 Water Disinfection Systems Learn More
    $54.99 Retail Price:  $89.00
  11. CMB-510-HF Advanced Water Products 10-inch x 4.5-inch Replacement Sediment Filter

    Advanced Water Products CMB-510-HF Whole House Filter for IHS12-D4 System

    Made for the Trojan UV Max IHS12-D4 Water Disinfection System Learn More
  12. 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
  13. CB6 OmniFilter Whole House Filter Replacement Cartridge

    CB6 OmniFilter Whole House Water Filter Cartridge

    Fits any brand of whole house water filtration system that uses 9 3/4 x 4 1/2 water filter cartridges Learn More
    $83.99
  14. 3M Aqua-Pure AP410 Water Filter Cartridges

    AP410 3M Aqua-Pure Water Filter Cartridge Set (2-Pack)

    Fits the 3M Aqua-Pure AP400 and AP400SS Point of Use water filtration systems Learn More
    $64.99 Retail Price:  $71.29
  15. PCC-1 Pentek Undersink Filter Replacement Cartridge

    PCC-1 Pentek Undersink Filter Replacement Cartridge

    Fits Pentek standard water filter housings Learn More
    $41.99 Retail Price:  $53.23
  16. P1 Pentek Whole House Filter Replacement Cartridge

    P1 Pentek Whole House Filter Replacement Cartridge

    Fits any standard housing that uses 9 3/4-inch x 2 1/2-inch replacement filter cartridges Learn More
    $7.99
  17. 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
  18. P1-D Culligan Level 4 Whole House Filter Replacement Cartridge (2-Pack)

    P1-D Culligan Whole House Water Filter Replacement Cartridge (2-Pack)

    Fits Culligan HF-150, HF-160, HF-360 HF-365, and any brand of whole house water filtration system that uses standard 9 3/4 x 2 1/2 filter cartridges Learn More
    $12.99

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