Discount Water Filters and Air Filters at Discount Filter Store.com

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Undersink Water Filters & Systems

Transform the water served from your tap or faucet into a premium quality beverage with an under sink water filter.

With over 250+ under sink water filter systems and undersink replacement filters available in a wide range of flow rates, colors/finishes, prices, and filter life’s, we’ve got an undersink filter for every home. Choose from some of the best under sink water filters including the Crystal Quest 7 Stage Under Sink Fluoride Water Filter System, the Culligan® Level-4 Easy Change Undersink Drinking Water System, and the 3M Filtrete™ Undersink Advanced Water Filter System.

Not sure, which under the sink water filter is right for your home? Give us a call 1-800-277-3458; our experts will help you choose the perfect under sink filter to address all of your water quality concerns, no matter how monumentous they may seem.

Note: All of our under sink filters and under sink water filter systems are backed by our 100% Price Match Guarantee. Meaning if you find a particular under sink water filter for less than our listed price, we’ll match the competitors lower price. Shopping for home water filters has never been easier.

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  1. TIER1-GAC-10 Pentek Undersink Replacement Cartridge by Tier1

    TIER1-GAC-10 Pentek Undersink Replacement Cartridge by Tier1

    Fits standard 9 3/4-inch x 2 1/2-inch replacement filter cartridges. Learn More
    $12.99
  2. TIER1-GAC-20BB Replacement Granular Activated Carbon Filter by Tier1

    TIER1-GAC-20BB Replacement Granular Activated Carbon Filter by Tier1

    The TIER1-GAC-20BB replacement granular activated carbon filter by Tier1, is universal for a variety of water filter housings sized 20x4.5 inches. Learn More
    $37.99
  3. WFDW120009W DuPont Universal Drinking Water Filter System

    WFDW120009W DuPont Universal Drinking Water Filter System

    Fits DuPont WFDW 2000 series, 4000 series, 7000 series Learn More
  4. WFDWC20001 DuPont Universal Drinking Water Carbon Block Cartridge

    WFDWC20001 DuPont Universal Drinking Water Carbon Block Cartridge

    Fits WFDW120009W DuPont Universal Drinking Water Filter System and other brands of 10-inch standard-size filter systems Learn More
  5. D-25 Culligan Comparable Undersink Replacement Cartridge by Tier1

    D-25 Culligan Comparable Undersink Replacement Cartridge by Tier1

    Fits standard 9 3/4-inch x 2 1/2-inch replacement filter cartridges. Learn More

    As Low As $0.00 Per Filter

  6. WCC Amercian Plumber Comparable Undersink Replacement Cartridge by Tier1

    WCC Amercian Plumber Comparable Undersink Replacement Cartridge by Tier1

    Fits standard 9 3/4-inch x 2 1/2-inch replacement filter cartridges. Learn More

    As Low As $0.00 Per Filter

  7. CC-10 Pentek Comparable Undersink Replacement Cartridge by Tier1

    CC-10 Pentek Comparable Undersink Replacement Cartridge by Tier1

    Fits standard 9 3/4-inch x 2 1/2-inch replacement filter cartridges. Learn More

    As Low As $0.00 Per Filter

  8. WRC25HD20 American Plumber Comparable Granular Activated Carbon Filter by Tier1

    WRC25HD20 American Plumber Comparable Granular Activated Carbon Filter by Tier1

    The WRC25HD20 American Plumber comparable replacement granular activated carbon filter by Tier1, is universal for a variety of water filter housings sized 20x4.5 inches. Learn More

    As Low As $0.00 Per Filter

  9. GAC20-BB Pentek Comparable Granular Activated Carbon Filter by Tier1

    GAC20-BB Pentek Comparable Granular Activated Carbon Filter by Tier1

    The GAC-20BB Pentek comparable replacement granular activated carbon filter by Tier1, is universal for a variety of water filter housings sized 20x4.5 inches. Learn More

    As Low As $0.00 Per Filter

  10. AP817-2 Aquapure Comparable Granular Activated Carbon Filter by Tier1

    AP817-2 Aquapure Comparable Granular Activated Carbon Filter by Tier1

    The AP817-2 Aquapure comparable replacement granular activated carbon filter by Tier1, is universal for a variety of water filter housings sized 20x4.5 inches. Learn More

    As Low As $0.00 Per Filter

  11. RFC20-BB Pentek Comparable Granular Activated Carbon Filter by Tier1

    RFC20-BB Pentek Comparable Granular Activated Carbon Filter by Tier1

    The RFC20-BB Pentek comparable replacement granular activated carbon filter by Tier1, is universal for a variety of water filter housings sized 20x4.5 inches. Learn More

    As Low As $0.00 Per Filter

  12. OmniFilter RS12-SS6-05 Polypropylene Sediment Filter

    OmniFilter RS12-SS6-05 Polypropylene Sediment Filter

    Standard 10 inch by 2.5 inch size fits many common filter housings Learn More
    $4.99 MSRP:  $11.99
  13. 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 MSRP:  $26.44
  14. WGC478 American Plumber Undersink Compact Filter Replacement Cartridge

    WGC478 American Plumber Undersink Compact Filter Replacement Cartridge

    Fits American Plumber WGC478 Learn More
    $13.99 MSRP:  $14.94
  15. WGCHD American Plumber Undersink Water Filter Replacement Cartridge

    WGCHD American Plumber Undersink Filter Replacement Cartridge

    Fits American Plumber W10-PR and W15-PR and most other heavy duty water filter housings Learn More
    $34.99 MSRP:  $48.29
  16. 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
    $18.49 MSRP:  $28.99
  17. 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
  18. 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
  19. SFM2 OmniFilter Undersink Water Filter System

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