Editorial standards

What we do

We compare whole house water filtration systems on specifications, third party certifications, prices, and policies. Every comparison is built from manufacturer spec sheets, NSF International certification listings, customer review aggregates, and warranty and installation documentation. When we state a fact, we name the source.

What we never do

We do not pretend to test systems we have not tested. You will never read "we installed twelve systems in our lab" on this site, because we did not. Our methodology is spec and certification based comparison, and we say so plainly. Any hands-on experience we do gain gets labeled as exactly what it is.

We do not sell placements. Rankings are never for sale, and manufacturers cannot pay for a better position. When we join affiliate programs, the commission structure does not influence rankings, and we disclose the relationships.

We do not make health claims beyond what certifications support. If a system is NSF certified to reduce a contaminant, we say so and cite the listing. If it is not certified, we say that too. Contaminant removal claims without certification backing do not appear on this site.

How we handle prices

Prices change. Every guide shows its last updated date, and we recheck manufacturer pricing on a regular cycle. Always confirm the current price on the product page before buying.

Corrections

If you spot an error, tell us and we will fix it and note the correction. Accuracy is the entire product here.