Will a standard filter remove arsenic?

Usually not, so it is best not to count on the filter you already have. Most carbon pitchers and faucet filters are not certified for arsenic. Look instead for a reverse-osmosis system certified to NSF/ANSI 58, and check whether it covers arsenic III, arsenic V, or both - that detail matters for your water.

Contaminant · Water

Arsenic

EPA MCL 10 ppb. 2 of the water filters we score hold an accredited NSF, WQA, or IAPMO certification to reduce Arsenic, and 7 more market it with no accredited certification we could verify. A claim is not a certification.

What it is

Arsenic sounds alarming, but the practical story is simpler than the name: it is a naturally occurring element that dissolves into groundwater from rock and soil, and it can also come from industrial or agricultural sources. It turns up most in private wells and in some regional aquifers, and like nitrate it gives no clue at the tap - it is tasteless and colorless, so testing is the only way to know.

Why it matters

The EPA sets a maximum contaminant level of 10 parts per billion for arsenic in public drinking water, and that is the regulatory reference point we use. What we score is whether a filter is certified to reduce arsenic, not any health outcome. One detail that affects what you buy: arsenic exists in two forms (III and V), and certified systems are tested for the specific form they treat - so it is worth knowing which one your water has.

What removes it

The most common certified route is reverse osmosis (NSF/ANSI 58); some systems are certified specifically for arsenic, and a good certification will tell you whether it covers arsenic III, arsenic V, or both. The thing to rule out: ordinary carbon filtration does not reliably remove arsenic, so do not lean on a basic pitcher here.

Reference: EPA National Primary Drinking Water Regulations; arsenic MCL 10 ppb.

Scored filters certified for Arsenic

7.5
AquaTru Classic Countertop RO
A no-plumbing countertop 4-stage RO purifier certified to NSF standards for lead, PFAS, fluoride and arsenic with an efficient drain ratio.
6.6
Waterdrop G3P800 Tankless RO
A tankless 800 GPD reverse-osmosis system IAPMO-certified to NSF/ANSI 42, 53, 58 and 372 for a broad contaminant list including lead, PFAS, arsenic, nitrate and fluoride.

Marketed for Arsenic, but not certified

These scored filters market Arsenic reduction but we found no accredited NSF, WQA, or IAPMO certification for it - "tested to" is not "certified to." Absence of certification is not proof a product fails to reduce it, only that we found no independent verification.

6.1
iSpring RCC7 5-Stage RO
A 5-stage 75 GPD under-sink RO. The base RCC7 is NSF-certified for TDS reduction only - the lead, fluoride and arsenic claims belong to other iSpring SKUs, not this model.
4.9
Express Water RO5DX 5-Stage RO
A 5-stage under-sink RO whose contaminant figures come from third-party lab testing (QFT Laboratory) to NSF/ANSI methods; we found no accredited NSF, WQA or IAPMO certification listing for this model.
4.3
Home Master TMAFC-ERP Artesian RO
A 7-stage RO with permeate pump, a 1:1 waste ratio and alkaline remineralization - but the complete system holds no third-party performance certification.
4.0
APEC ROES-50 Essence RO
An affordable 50 GPD under-sink RO system, WQA-certified to NSF/ANSI 58 for TDS - but it markets lead and arsenic removal it is not separately certified for.
3.7
SpringWell CF1 Whole House
A 4-stage catalytic-carbon whole-house filter rated for a million gallons that uses NSF-certified media but is not certified as a complete system.
2.5
Clearly Filtered Pitcher
Certified only to NSF/ANSI 42 and 372, its 365+ contaminant claims come from non-accredited lab testing, not health-effects certification.
1.7
Clearly Filtered 3-Stage Under-Sink
A three-stage under-sink system the brand says targets 232+ contaminants, but its performance is lab-tested to NSF protocols rather than third-party certified.

FAQ

Will a standard filter remove arsenic?: Usually not, so it is best not to count on the filter you already have. Most carbon pitchers and faucet filters are not certified for arsenic. Look instead for a reverse-osmosis system certified to NSF/ANSI 58, and check whether it covers arsenic III, arsenic V, or both - that detail matters for your water.