Best water filter for PFAS at the tap: what to look for

Start with your own water, not the product page

A filter is a response to a result. Before you buy one, check what your utility actually reported: find your utility on our state pages and look at its PFOA and PFOS numbers from EPA’s UCMR 5 testing. If your utility’s results are non-detect, you may not need a PFAS filter at all. If you are on a private well, the utility data does not apply and a lab test is the only way to know (how to test).

Which technologies reduce PFAS

EPA’s consumer page says that granular activated carbon (GAC), ion exchange resin (IX) and reverse osmosis (RO) point-of-use systems it studied “can greatly reduce PFAS levels”, and that they only work if maintained to the manufacturer’s replacement schedule. The Minnesota Department of Health reaches the same conclusion: carbon filters and reverse osmosis membranes have been shown to be effective, while “water softeners or iron filtration systems, are not likely to remove PFAS” and boiling does not remove PFAS.

• Carbon (GAC or carbon block): pitchers, faucet-mount filters and under-sink cartridges. EPA’s page gives a cost range for each type, with maintenance extra. Capacity is limited, so replacement timing matters.
• Ion exchange: often combined with carbon in a cartridge.
• Reverse osmosis: an under-sink system that pushes water through a membrane. EPA says it wastes about one gallon for every gallon treated; see reverse osmosis pros and cons.

The certification to look for

EPA, the CDC and the Minnesota Department of Health all point buyers to NSF/ANSI 53 (health-effects filters) or NSF/ANSI 58 (reverse osmosis) with a PFAS reduction claim. Certification can come from NSF, IAPMO R&T, WQA, CSA Group or UL. The claim is specific to a model and cartridge, so find that exact product on the certifier’s listing, not just a logo on the box. We explain the letters in NSF/ANSI certifications explained.

A certificate is not proof of 4 ppt

EPA’s 2024 limit for PFOA and PFOS is 4 parts per trillion each. EPA’s own consumer page notes that the filter certification standards, as of April 2024, did not yet show a filter will remove PFAS to those levels. The standard has since been updated: according to ANSI’s summary, NSF/ANSI 53-2025 sets PFOA and PFOS effluent limits of 4.0 ppt each, matching EPA’s limits, and the joint NSF, IAPMO and WQA timeline says certified products must meet the updated PFAS requirements by January 1, 2030. In the meantime, many listings on file were tested to older criteria. When you read a performance data sheet, look at the effluent (filtered water) numbers and the test conditions, not only the word “certified”.

A short buying checklist

1. The product is listed by a certifier for PFOA and PFOS reduction under NSF/ANSI 53 (or 58 for RO) for your exact model and replacement cartridge.
2. You can state the cartridge’s rated life in gallons or months and will replace it before then.
3. It treats the water you drink and cook with. A single-tap filter treats only that tap, so decide which taps matter to you.
4. If you also worry about lead, the listing carries a separate lead claim (lead filters).

Contact your state environmental or health agency and your utility for their recommendations; EPA’s page says the same.