NSF/ANSI water filter certifications
NSF/ANSI standards tell you exactly what a water filter is independently certified to do. Pick the standard that matches your concern to see the filters certified under it — verified against NSF, IAPMO, and WQA listings, not marketing claims.
NSF/ANSI Standard 53
Health Effects (lead, VOCs, cysts, etc.)
11 certified filters →
NSF/ANSI Standard 401
Emerging Contaminants (PFAS, pharmaceuticals)
13 certified filters →
NSF/ANSI Standard 42
Aesthetic Effects (chlorine, taste, odor)
18 certified filters →
NSF/ANSI Standard 58
Reverse Osmosis Systems
16 certified filters →
NSF/ANSI Standard 55
Ultraviolet Light Treatment
View standard →
NSF/ANSI Standard 44
Cation Exchange Softeners
1 certified filter →
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