About H2O Insider
Why we exist
Most "best water filter" articles are written by people who have never installed the filter. Many repeat certification claims from the box without checking a single listing. Families worried about lead in their pipes or PFAS in their well deserve better than that.
H2O Insider exists to be the resource we wished existed when we were trying to figure out what to put under our own sinks. We buy and use every filter we review. We check every certification claim against the NSF, IAPMO and WQA listings, and record the date we checked. We do not run lab tests, and we never imply a lab result we do not have. We disclose our affiliate relationships and publish our scoring method.
We earn affiliate commissions when readers buy through our links. That is how we pay for the filters. Those commissions do not influence our recommendations. If the best product doesn't have an affiliate program, we recommend it anyway.
Our review standard
We buy every filter we review and use it at home. Where we report a measurement, such as a TDS meter reading or a flow rate, we say what we measured and when. A TDS meter cannot detect lead or PFAS, so we never use one as evidence for either.
We check certification claims against all three directories that certify water filters to NSF/ANSI standards: NSF, IAPMO and WQA. Many filters appear in only one of them. A claim we cannot find in any listing gets no credit in our scoring.
Our team
Every review has a byline, and every byline is a real person.
Rob founded H2O Insider after spending two years unable to find trustworthy, independent water filter reviews online. He buys and uses every filter the site reviews, and checks each certification claim against the NSF, IAPMO and WQA listings.
Sarah writes our contaminant guides and checks our certification coverage for technical accuracy.
Mike has installed more water treatment systems than most people have reviewed. He evaluates installation complexity, calls out products that claim DIY but require a plumber, and contributes the practical installation guidance throughout our reviews. Based in Oakland, CA.
Editorial independence
H2O Insider does not accept manufacturer payments, sponsored placements, or paid reviews. Brands cannot purchase favorable coverage, request changes to published reviews, or influence our scoring method.
If we get something wrong — a certification claim, a performance figure, a product update — we correct it promptly and note the correction date. We do not silently revise published content.