PFAS show up in the news a lot, and the advice around them is easy to get wrong. I’m Ree Fonteyn, and this page sets out the steps I’d follow myself: find out whether PFAS is actually in your water, then pick a filter type that has a current certification to reduce it.
I don’t lab-test or home-test filters. What I research is certifier listings, manufacturer documents, filter costs, and EPA and utility data. You can read more in How We Review. This page doesn’t recommend products. It’s meant to help you know what to look for.
What PFAS are (and why they’re called forever chemicals)
PFAS (per- and polyfluoroalkyl substances) are a large family of man-made chemicals. They’ve been used in nonstick pans, stain- and water-resistant fabrics, food packaging, and some firefighting foams. They break down very slowly, so people call them “forever chemicals.” They can build up in the environment and get into groundwater and surface water.
The family has thousands of chemicals in it. The two most studied are PFOA and PFOS, so they’re also the two that most filter certifications cover. The EPA’s PFAS overview is a good plain-language place to start.
What the US rules say right now
In April 2024 the EPA finalized the first national drinking water rule for PFAS. The EPA PFAS rule page lists the details. The 2024 rule set:
- Enforceable limits (MCLs) of 4.0 ppt (parts per trillion) each for PFOA and PFOS.
- Limits of 10 ppt each for PFHxS, PFNA, and HFPO-DA (often called “GenX”).
- A “hazard index” limit for mixtures of PFHxS, PFNA, HFPO-DA, and PFBS.
- Initial monitoring by 2027, and action to fix any exceedances of the limits by 2029.
The rule is being revised. On May 14, 2025 the EPA announced it would keep the PFOA and PFOS limits and reconsider the others. On May 18, 2026 it put forward two proposed rules. The first keeps the 4.0 ppt PFOA and PFOS limits but lets water systems ask for two more years, to 2031, to comply. The second would rescind the limits for PFHxS, PFNA, HFPO-DA, and the hazard index. Both are still proposals, so the 2024 rule stays in place until a final rule replaces it. Check the EPA PFAS rule page for where things stand today. Also, a national rule doesn’t cover private wells, and some states set their own stricter limits.
Is PFAS in your water?
Before you buy anything, check your water. Here’s where to look:
- Your Consumer Confidence Report (CCR). Every community water system has to publish a yearly water quality report. You can usually find yours on your utility’s website or through the EPA CCR page. Look for PFOA, PFOS, or “PFAS” in the tables.
- UCMR 5 data. Between 2023 and 2025, the EPA’s Fifth Unregulated Contaminant Monitoring Rule had many public water systems sample for 29 PFAS (plus lithium). The EPA released the final dataset in August 2026, and you can search the results by system in the UCMR 5 Data Finder.
- The EWG Tap Water Database. The EWG database pulls utility data together in one place. EWG compares results against its own guidelines, which are stricter than the EPA’s, so expect to see more “exceedances” there than in your CCR.
- Private wells. Nobody tests a private well for you. Use a state-certified lab that offers PFAS testing, and see the EPA private wells page for how to find one.
If your utility or health department has issued a PFAS advisory, follow its guidance first.
Filter types that reduce PFAS
If you find PFAS, or you just want a margin of safety, these are the filter types to look at. What matters most is a current certification for the exact model and the exact contaminant.
| Filter type | Standard to look for | Typical use | My guide |
|---|---|---|---|
| Under-sink reverse osmosis (RO) | NSF/ANSI 58, PFOA/PFOS (or “total PFAS” if listed) | Drinking and cooking water at one tap | Best Under-Sink RO |
| Activated carbon / solid carbon block (under-sink, faucet, countertop) | NSF/ANSI 53, PFOA/PFOS | Point-of-use filtering without RO wastewater | Start Here |
| Water filter pitchers | NSF/ANSI 53, PFOA/PFOS. Only if the model is listed | Small households, renters | Best Water Filter Pitchers |
RO usually gives the widest reduction because the membrane blocks a broad range of contaminants. Carbon block can also do the job, but performance varies a lot from one design to another. That’s why the listing matters more than the filter type.
What doesn’t help
- Water softeners. A softener swaps hardness minerals for sodium or potassium. It isn’t designed to reduce PFAS. Softeners are useful for scale, as I explain in Best Water Softeners, but PFAS isn’t what they’re for.
- Boiling. Boiling doesn’t remove PFAS. NSF notes that boiling can concentrate them, because the water evaporates and the PFAS stay behind.
- Uncertified “PFAS-free” or “removes forever chemicals” claims. A marketing claim on a box isn’t the same as a certification. Check the listing yourself.
How to check a PFAS certification claim
This step matters more than anything else on the page.
Certified vs. “tested to.” “Certified” means an independent certifier, such as NSF, IAPMO R&T, or the WQA, has listed that exact model for that exact contaminant. “Tested to NSF/ANSI 53” usually means the maker or a lab it hired ran the test, and no ongoing certification sits behind it. That can still be useful information, but it’s not the same thing.
Which standards. PFAS reduction claims are now certified under NSF/ANSI 53 (carbon and other point-of-use filters) and NSF/ANSI 58 (reverse osmosis). Look for PFOA and PFOS on the listing, and for “total PFAS” only where the listing actually says so. The EPA notes that certifications current as of April 2024 didn’t yet show that a filter gets PFAS down to the new 4.0 ppt limits. NSF has since been updating the standards, so check what the listing actually claims.
About P473. NSF’s older PFAS protocol, NSF P473, has been retired. Its PFOA/PFOS test methods were moved into NSF/ANSI 53 and 58. Older packaging and product pages may still mention it. Don’t rely on that alone. Look up the current listing.
How to check:
- Note the exact model number of the filter and its replacement cartridge.
- Search the certifier’s own database, such as the NSF certified listings, or IAPMO R&T or WQA for their listings.
- Make sure PFOA/PFOS (or total PFAS) appears for that model under NSF/ANSI 53 or 58.
- Name the right certifier. A model listed by IAPMO or WQA isn’t “NSF certified,” even though it’s certified to an NSF/ANSI standard.
Even a certified filter reduces PFAS. It doesn’t guarantee that it removes all of them.
Keep it working: replace filters on schedule
A certification only holds when you replace cartridges on time. Activated carbon has limited capacity, and once it’s spent it stops reducing PFAS the way the listing says. Ignoring the change indicator is the most common way a good filter turns into an expensive jug.
- Follow the maker’s replacement interval in gallons or months, whichever comes first.
- Replace RO pre-filters and membranes on the maker’s schedule.
- Count the ongoing cartridge cost before you buy. A cheap unit with expensive filters you’ll skip isn’t a bargain.
FAQ
Does boiling water remove PFAS?
No. Boiling doesn’t remove PFAS, and it can concentrate them as the water evaporates.
Is bottled water PFAS-free?
Not automatically. Bottled water quality varies by brand and source. If you rely on it, check the brand’s water quality report.
Should I worry about PFAS when showering?
Most guidance focuses on drinking and cooking water. Ask your health department if you have specific concerns. A point-of-use filter at the kitchen tap is where most households start.
Do refrigerator filters reduce PFAS?
Some do. Check the listing for your exact fridge filter model under NSF/ANSI 53 with PFOA/PFOS. Don’t assume it covers PFAS.
Where to go next
- New here? Start with Start Here.
- Want the widest reduction at one tap? See Best Under-Sink RO.
- Want something simple? See Best Water Filter Pitchers.
- Thinking about a softener? Read Best Water Softeners, and remember softeners don’t address PFAS.
- Narrow Q&A: Is there a water filter that removes forever chemicals? A shorter page on that single question; this guide is the fuller version.
- How I research: How We Review
Questions? Email me at contact@filteredwaterwise.com.
Sources
- EPA, PFAS National Primary Drinking Water Regulation: https://www.epa.gov/sdwa/and-polyfluoroalkyl-substances-pfas
- EPA, PFAS overview: https://www.epa.gov/pfas
- EPA, Consumer Confidence Reports: https://www.epa.gov/ccr
- EPA, UCMR 5: https://www.epa.gov/dwucmr/fifth-unregulated-contaminant-monitoring-rule
- EPA, Private Wells: https://www.epa.gov/privatewells
- EWG Tap Water Database: https://www.ewg.org/tapwater/
- EPA, Identifying Drinking Water Filters Certified to Reduce PFAS: https://www.epa.gov/water-research/identifying-drinking-water-filters-certified-reduce-pfas
- NSF, PFOA/PFOS in Drinking Water: https://www.nsf.org/consumer-resources/articles/pfoa-pfos-drinking-water
- NSF, Forever Chemicals and the Advancement of Filtration Standards: https://www.nsf.org/knowledge-library/forever-chemicals-advancement-filtration-standards
- NSF certified drinking water treatment listings: https://info.nsf.org/Certified/DWTU/