Best under-sink water filters
Under-sink systems treat water at the kitchen tap and deliver the lowest cost per gallon of any point-of-use filter. The health-standard models (NSF/ANSI 53 and 58) also cover the most contaminants — lead, VOCs, cysts, and often PFAS.
893 certified under-sink models in our database · ranked by independent certification and cost per gallon · no paid placement.
EcoPure ECOP30
Certified to reduce 16 contaminants, including lead. About 6.2¢ per gallon.
How the top under-sink filters compare
| Filter | Certified for | Contaminants | Price | ¢/gal | |
|---|---|---|---|---|---|
| EcoPure ECOP30 | Arsenic, Barium, Cadmium +13 | 16 | $219.99 | 6.2 | Buy |
| AFWFilters Pentair GRO-575B | Arsenic, Atrazine, Barium +12 | 15 | $809 | 13.8 | Buy |
| Multipure Aquaperform | Arsenic, Asbestos, Chlorine / chloramine +11 | 14 | $765 | — | Buy |
| OMNIFilter RO2050 | Arsenic, Barium, Cadmium +10 | 13 | $21.69 | — | Buy |
| Everpure Conserv 75E | Arsenic, Barium, Cadmium +10 | 13 | $478.7 | — | Buy |
| Pentek Pentair RO-2550 | Arsenic, Barium, Cadmium +8 | 11 | $17.22 | — | Buy |
| Multipure Aquamini | Asbestos, Chlorine / chloramine, Cryptosporidium +6 | 9 | $395 | — | Buy |
| iSpring RCC7AK-UVBLK | Asbestos, Barium, Cadmium +5 | 8 | $354.99 | — | Buy |
| iSpring RCC7UV | Asbestos, Barium, Cadmium +5 | 8 | $328.29 | — | Buy |
| Everpure Residential H-1200 | Chlorine / chloramine, Cryptosporidium, Giardia +3 | 6 | $349.01 | 34.9 | Buy |
| OMNIFilter CBF3 | Chlorine / chloramine, Cryptosporidium, Giardia +3 | 6 | $100.94 | 14.7 | Buy |
| EcoPure ECOP20 | Chlorine / chloramine, Cryptosporidium, Giardia +3 | 6 | $88.71 | 32.9 | Buy |
See all 1,882 under-sink filters →
How to choose an under-sink filter
Match it to your water. The best filter is the one certified for what's actually in your water. Look up your ZIP to see your contaminants, then confirm the filter's certified claim list covers them.
Certification tiers to know. NSF/ANSI 42 = aesthetic (taste, chlorine); NSF/ANSI 53 = health (lead, VOCs, cysts); NSF/ANSI 401 = emerging contaminants (pharmaceuticals). A filter is only credited for the exact claims it lists.
Installation & upkeep. Mounts under the sink; connects to the cold line. Basic DIY. Expect to replace the element about 2×/year; the running cost of refills usually matters more than the sticker price.
Frequently asked
What's the most important thing when buying an under-sink water filter?
Certification for the specific contaminant you care about. "NSF certified" is not one thing — a filter certified for lead (NSF 53) may do nothing for PFAS or fluoride, and NSF 42 only covers taste and chlorine. Check the exact certified claim, which we list for every filter.
Are these filters actually certified, or just "tested to" a standard?
Every filter here is listed in the public certification database of NSF, WQA, or IAPMO — meaning an independent body verified its claims. We never count "tested to" marketing claims that aren't backed by a listing.
How do you rank them — does anyone pay for placement?
No. We rank by independent certification coverage and true cost per gallon, computed before any buy link is attached. See our methodology.
Rankings use NSF/WQA/IAPMO public certification data and computed cost per gallon. We only attach a buy link when we can verify the retail listing is the certified model. Some links are affiliate links — see our disclosure.