Is ZeroWater NSF certified?

Last reviewed July 2026.

Yes. ZeroWater filters are listed by IAPMO against NSF/ANSI standards including 53 — the health-effects standard that covers lead — so the lead claim is one you can actually verify in a public listing.

What the listing actually says

ZR-002: System certified by IAPMO R&T to NSF/ANSI 42 (chlorine) and 53 (lead, hexavalent chromium, PFOA/PFOS, mercury). Not in the NSF listing database — IAPMO is a separate accredited certifier.

What those standard numbers mean

• NSF/ANSI 42 — aesthetic effects (chlorine, taste and odour). Not a health claim.
• NSF/ANSI 53 — health effects. This is the standard that covers lead.

Verify it yourself: every ZeroWater row above links the certifier's own listing. If a number here disagrees with the listing, the listing wins — tell us and we'll fix it.

What the certified claim costs to run

Certification is per model, and so is the running cost. The cheapest ZeroWater model carrying the claim is the 5-Stage Replacement Filter (2-pack) (ZR-002) at about $18.50 per filter for a certified 15 gallons — $1.233 per certified gallon.

That capacity is what the certifier tested to, not a marketing estimate. For one person drinking about half a gallon a day it is roughly about 4 weeks per filter; for a family of four, closer to 8 days. Run past the rated capacity and the claim no longer applies — the media is exhausted even though the filter still passes water.

See how ZeroWater ranks on cost per certified gallon against every filter we track →

Related: Does ZeroWater remove lead? · Does ZeroWater remove PFAS?

We do not test filters — we index what accredited certifiers publish, with attribution, and make no health or treatment claims. A certification covers a specific model against a specific standard; it is not a general seal of quality. We are not affiliated with NSF International.