Contaminant Reduction Claims
At NSF, we certify various water treatment systems, from filtration to reverse osmosis, which are designed to reduce contaminants. We have listed certified products based on the pollutants we regularly ask about to help you find the best water filter for your home or office. Remember that no systems may be certified to reduce that specific contaminant if a filter type is not listed. Contact us with your questions.
Lead
View all filters and systems certified by NSF to reduce lead.
- Water Pitchers With Filters
- Faucet Filters
- Under-Sink Filters
- Reverse Osmosis Filters
- Counter-Top (Manual-Fill) Filters
- Counter-Top Filters Connected to a Sink Faucet
- Refrigerator Filters
- Aftermarket Refrigerator Filters
- Integrated Refrigerator Filters
Arsenic (Pentavalent) for Treating Incoming Levels of <=50 ppb
View all filters and systems certified by NSF to reduce arsenic less than 50 ppb.
Bacteria/Coliform/Cyst/Virus
Chlorine
View all filters and systems certified by NSF to reduce chlorine.
- Whole House Systems
- Faucet Filters
- Water Pitchers With Filters
- Counter-Top Filters Connected to a Sink Faucet
- Counter-Top (Manual Fill) Filters
- Under-Sink Filters
- Reverse Osmosis Systems
- Refrigerator Filters
- Integrated Refrigerator Filters
- Aftermarket Refrigerator Filters
Chloramine
View all filters and systems certified by NSF to reduce chloramine.
- Faucet Filters
- Counter-Top Filters Connected to a Sink Faucet
- Counter-Top (Manual-Fill) Filters
- Under-Sink Filters
- Reverse Osmosis Systems
Chromium (Hexavalent)
View all filters and systems certified by NSF to reduce hexavalent chromium.
Fluoride
Nitrate/Nitrite
PFOA/PFOS
View all filters and systems certified by NSF to reduce PFOA/PFOS.
- Counter-Top Filters Connected to a Sink Faucet
- Under-Sink Filters
- Reverse Osmosis Systems
- Refrigerator Filters
- Aftermarket Refrigerator Filters
- Refrigerator Filters (Integrated)
- Water Pitchers With Filters
- Whole-House Filters
Total Trihalomethanes (TTHM) and Volatile Organic Compounds (VOCs)
View all filters and systems certified by NSF to reduce VOCs including TTHM.
How NSF Can Help You

What’s New with NSF

NSF Hosts First External Review Panel for ‘NSF/KWTC 555’ with Key Asian Water Authorities
August 3, 2026Joint standard development gains momentum to enhance confidence in Asia’s water industry and advance drinking water safety.
NSF Achieves European Accreditation for Drinking Water Product Certification Ahead of 2027 EU Deadline
July 22, 2026The ISO/IEC 17065 accreditation from BELAC complements NSF’s testing capacity, enabling end-to-end support for EU Drinking Water Directive (DWD) readiness ahead of the January 2027 deadline.
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July 13, 2026Milestone certification sets a new benchmark for small-scale fishery sustainability and social responsibility.