How we review PFAS filters

A filter has to clear three gates before we will write about it for PFAS.

1. It is sold in the United States right now, with a working product page.
2. It makes a PFAS claim, or it uses a technology EPA points to for PFAS: reverse osmosis, or activated carbon and anion exchange.
3. There is something to check. A claim with no certification, no lab report and no data sheet behind it gets graded, not featured.

We do not rank a maker higher because it runs an affiliate program. Two of the products on this site pay us nothing at all.

This is where most filter reviews go wrong, so here is the detail.

A product certified to NSF/ANSI 53 is not automatically certified for PFAS. Standard 53 covers dozens of contaminants. A filter can hold 53 for lead and carry no PFAS claim at all. The standard number alone tells you almost nothing.

So for every product we record three things separately:

• The certifying body.EPA recognises five accredited bodies: NSF, WQA, IAPMO R&T, CSA Group and UL.
• The standards actually held, in full.
• Whether PFAS is on that certification. A single yes or no field. If the answer is no, we say so on the card even when the maker prints PFAS numbers on the box.

We also watch the wording. "Certified to NSF/ANSI 53" and "tested to comply with NSF/ANSI 53" are not the same claim. The second means a lab ran the method. Nobody certified the result. One product on this site uses exactly that wording and we flag it on its card.

You can check any of this yourself. Every card links to the certifier's public listing.

When a maker publishes independent lab data instead of a certification, we look for four things: which lab ran it, what accreditation that lab holds, which PFAS compounds were actually measured, and what the starting concentration was.

That last one matters more than people expect. A filter tested against a very high starting concentration and a filter tested against a low one can both report "99% reduction" and leave very different amounts of PFAS in the glass.

If a report does not name the lab or the compounds, we treat the number as the maker's claim, not as independent evidence.

Every product carries one of four grades. The grade describes the strength of the evidence, not how much we like the product.

We do not recommend Evidence D products for PFAS removal. They may be fine filters for other jobs.

Filter prices move constantly, and review sites are notorious for quoting numbers that went stale years ago. So we do two things.

Every price on this site carries the date we checked it. If we cannot keep a price current, we do not print a number at all. We say "see current price" and send you to the seller.

We also quote the yearly cost wherever we can work it out, because the sticker price is the smaller number for most filters. A $99 pitcher that needs $180 of cartridges a year is not a $99 pitcher.

Within a category we sort by evidence grade first. After that we weigh fit for the reader described at the top of the page, then total cost over three years, then how easy the thing is to live with.

Commission rate is not an input. It never enters the sort.

Some links here are affiliate links. If you buy through one, the seller pays us a commission and you pay exactly the same price.

Right now we earn on links to Amazon and Waterdrop. Every other maker on this site is a plain link that pays us nothing. We link to them anyway, because the job of the page is to get you to the right filter.

No brand on this site has paid for placement, and none has been offered the chance to.

Certification listings and prices get re-checked on a rolling basis and every product card shows its own last-checked date. Regulatory pages get checked whenever EPA moves, which in 2026 has been often.

Every commercial page shows the date its evidence was last confirmed. If that date looks old to you, treat the numbers with suspicion and tell us.

We get things wrong. When we do, we fix the page and say what changed rather than quietly editing it.

If you spot something out of date or plain wrong, tell us here. Certification status and filter specs change faster than any small site can track alone.