Does reverse osmosis remove PFAS?

Yes. Reverse osmosis (RO) is one of the most effective home treatments for PFAS: EPA research says RO and similar high-pressure membranes are typically more than 90 percent effective at removing a wide range of PFAS, including shorter-chain ones. To know that a particular system does it, look for a PFAS reduction claim certified under NSF/ANSI 53 or NSF/ANSI 58, and check that the listing names your model.

How RO takes PFAS out

An RO system pushes water through a thin barrier, typically in a three-, four- or five-stage process, and sends the water that does not pass through down the drain. In EPA's study of home units, RO, activated carbon and ion exchange systems "can greatly reduce PFAS levels".

The difference shows with short-chain PFAS. Carbon works well on longer-chain PFAS such as PFOA and PFOS, but shorter-chain PFAS such as PFBS and PFBA do not adsorb as well. High-pressure membranes such as RO remove shorter-chain PFAS too, which is where they pull ahead.

What a PFAS certification tells you

• Which standard. EPA tells buyers to look for certification to NSF/ANSI 53 or 58 for PFAS reduction. NSF/ANSI 58 is the reverse osmosis standard and 53 is the health effects standard. An RO system can hold both: one for its membrane, one for another stage.
• Which PFAS. In April 2024, EPA said filter certifications focus on PFOA and PFOS. Michigan's PFAS Action Response Team says filters can also be certified for total PFAS: seven PFAS combined (PFOA, PFOS, PFHxS, PFNA, PFHpA, PFBS and PFDA), reduced below 20 parts per trillion (ppt).
• How low. Pennsylvania's environmental agency gives the current acceptance level for PFOA and PFOS under NSF/ANSI 53 as 20 ppt. EPA's drinking water limits for PFOA and PFOS are 4.0 ppt each, and EPA says certification standards as of April 2024 do not yet indicate removal down to the levels EPA has now set.
• Other PFAS limits. Limits for PFHxS, PFNA, HFPO-DA and a mixture hazard index are still in federal rules, but EPA proposed rescinding them in a notice published on 20 May 2026. The proposal is not final. More in PFOA and PFOS limits explained.

RO systems in our data with a PFAS listing

Four of the 24 RO systems we track have a PFAS claim backed by an IAPMO R&T listing for that model. Status for all four: Certified (IAPMO listing, checked 16 Oct 2026). Each listing names PFOA and PFOS; none lists total PFAS.

In three of the four, the PFAS claim sits on a cartridge listed under NSF/ANSI 53, not on the RO membrane: AquaTru's AT2003 and AT2004, and Waterdrop's WD-G3-CB, which IAPMO's 58 listing calls a carbon filter. Those membranes have their own NSF/ANSI 58 listings for other contaminants, including lead (Waterdrop, AquaTru). EPA says filters work only if maintained according to the manufacturer's instructions, so that cartridge's schedule matters: Waterdrop rates its G3 CB filter for up to 12 months or 1,100 gallons.

Before you buy an RO system

• Check your water first. EPA says that if PFAS have not been measured in your water, or were measured below federal limits, a filter may not be useful to you.
• Plan for upkeep. RO needs new cartridges and a new membrane over time and, by EPA's estimate, wastes about one gallon of water for every gallon treated. Brands state their own figures; Waterdrop lists a 2:1 pure-to-drain ratio for the G3P600.
• Match the model. A listing covers only the models and cartridges it names. Look yours up in IAPMO R&T's directory, NSF's listings or WQA's directory.

The lead and PFAS status of all 24 RO systems is in Under-sink reverse osmosis compared by certification. For lower-cost certified options, see The lowest-cost ways to get a certified PFAS filter.