Water · Best-of

Best Under-Sink Water Filter

Under-sink carbon filters are the sweet spot for many homes: high capacity, good flow, no countertop clutter, and often broad certification. We rank them by what they are certified to remove and what they cost to run.

How we score: We rank under-sink-class filters by composite score (certified reduction, cost per gallon, capacity and flow).

1. 17.5

   Culligan US-EZ-4 Under-Sink

   The Culligan US-EZ-4 Under-Sink is a under sink water filter. It is third-party certified (IAPMO) to reduce chlorine taste and odor, chloramine, lead, mercury, cysts, VOCs, MTBE, turbidity, PFOA, PFOS. It is also marketed for pharmaceuticals, for which we found no accredited third-party certification (so we award no certification credit; this is not a finding that it fails to reduce them). Running cost works out to about $0.091 per gallon.

   • Certified to reduce: chlorine taste and odor, chloramine, lead, mercury, cysts, VOCs, MTBE, turbidity, PFOA, PFOS
   • Cartridge life: 500 gallons
   • Cost per gallon: $0.091
2. 27.2

   Aquasana AQ-5200 Under-Sink

   The Aquasana AQ-5200 Under-Sink is a under sink water filter. It is third-party certified (WQA) to reduce lead, chlorine taste and odor, chloramine, PFOA, PFOS, VOCs. Running cost works out to about $0.148 per gallon.

   • Certified to reduce: lead, chlorine taste and odor, chloramine, PFOA, PFOS, VOCs
   • Cartridge life: 500 gallons
   • Cost per gallon: $0.148
3. 36.8

   Frizzlife SK99 Under-Sink Filter

   The Frizzlife SK99 Under-Sink Filter is a under sink water filter. It is third-party certified (IAPMO) to reduce chlorine taste and odor, lead. It is also marketed for chloramine, mercury, cadmium, fluoride, VOCs, PFOA, PFOS, sediment, for which we found no accredited third-party certification (so we award no certification credit; this is not a finding that it fails to reduce them). Running cost works out to about $0.031 per gallon.

   • Certified to reduce: chlorine taste and odor, lead
   • Cartridge life: 1,600 gallons
   • Cost per gallon: $0.031
4. 45.7

   Waterdrop 10UA Under-Sink

   The Waterdrop 10UA Under-Sink is a under sink water filter. It is third-party certified (IAPMO) to reduce chlorine taste and odor. It is also marketed for PFAS, PFOA, PFOS, lead, sediment, for which we found no accredited third-party certification (so we award no certification credit; this is not a finding that it fails to reduce them). Running cost works out to about $0.005 per gallon.

   • Certified to reduce: chlorine taste and odor
   • Cartridge life: 8,000 gallons
   • Cost per gallon: $0.005
5. 54.1

   Epic Smart Shield Under-Sink

   The Epic Smart Shield Under-Sink is a under sink water filter. It is third-party certified (IAPMO) to reduce chlorine taste and odor, lead, VOCs, chloramine, mercury, cysts, pharmaceuticals. It is also marketed for PFAS, PFOA, PFOS, microplastics, for which we found no accredited third-party certification (so we award no certification credit; this is not a finding that it fails to reduce them). Running cost works out to about $0.177 per gallon.

   • Certified to reduce: chlorine taste and odor, lead, VOCs, chloramine, mercury, cysts, pharmaceuticals
   • Cartridge life: 651 gallons
   • Cost per gallon: $0.177
6. 61.7

   Clearly Filtered 3-Stage Under-Sink

   The Clearly Filtered 3-Stage Under-Sink is a under sink water filter. It carries no accredited NSF, WQA, or IAPMO certification - its contaminant claims are "tested to" lab results, not certifications. It is also marketed for chlorine taste and odor, fluoride, lead, PFAS, PFOA, PFOS, arsenic, mercury, chromium, pesticides, pharmaceuticals, VOCs, chloramine, for which we found no accredited third-party certification (so we award no certification credit; this is not a finding that it fails to reduce them). Running cost works out to about $0.198 per gallon.

   • Certified to reduce: nothing certified (claims are 'tested to' only)
   • Cartridge life: 2,000 gallons
   • Cost per gallon: $0.198