When you think of water filters, your first thought is likely in-door refrigerator dispensers and pourable pitchers with filters. Of course, we’ve come a long way since both of those mechanisms came on the kitchen scene. After all, did you know that full-on under-sink water filters exist? Better still, did you know that adding one to your plumbing can drastically improve not only the flavor, but the overall quality, of the water you consume? If not—or even if you’re simply researching whether or not a filtration system is necessary in your home—keep scrolling for everything there is to know about under-sink water filters, including which are worth making room for in your cabinet.
What does an under-sink water filter do?
Water filters come in many shapes, sizes, and levels of effectiveness—hence why faucet attachments, in-door mechanisms, and standalone filtered pitchers exist. But if your goal is to streamline your filtered water, nothing compares to under-sink water filters, which remove contaminants before the water even comes out of the faucet.
“Under-sink water filters are a popular way to get healthier, better-tasting water because they typically remove more contaminants than pitcher filters and even bottled water,” explains Derek Mellencamp, water-filtration expert and general manager at Aquasana, a water-filter manufacturer. “By connecting directly to the water source at its point of use, under sink filters use your home’s water pressure to force tap water through ultra-dense filtration media, giving it the force and speed to remove more contaminants, faster than a gravity-based system like a pitcher filter.”
What to look for in an under-sink water filter
Not all under sink filters are created equally—but that’s not a bad thing. Instead, it means that there are plenty of options based on your home and family’s needs.
Before looking for a filter, though, Mellencamp says it’s important to start by checking out your local water quality report. That way you can find out which, if any, contaminants are present in your area. “As part of the EPA’s Safe Drinking Water Act, all US water suppliers are required to send out an annual report that tells you where your water comes from and what’s in it,” he explains. “If you’re concerned about lead or any other toxins that may be specific to your home, you can also have your water tested by an independent lab.”
Once you determine which contaminants are at play, look for under-sink water filters with a Water Quality Association certification, says Steve Scheer, president of Brondell, a brand that produces water filters, among other household products. “You should look for efficiency, how many particulants it eliminates, and particularly for an RO [reverse osmosis] system, how much water is wasted.” (Mellencamp recommends also ensuring that your filtration system has been independently tested and certified to NSF/ANSI or IAPMO standards to address the contaminants you’re concerned about.)
According to Mellencamp, RO systems the ultimate under-water filter for maximum contaminant reduction. “They provide the most comprehensive protection and tackle even the more difficult substances like hexavalent chromium (think Erin Brockovich) and fluoride,” he says. “However, one downside of RO is that it typically also strips the beneficial minerals from water in the process.” Since you absorb most of your minerals through food, drinking demineralized water isn’t as big of deal as it may sound (you do it all the time if you’re not drinking natural spring or mineral water), but you can also remineralize yours by adding a pinch of Himalayan salt to your water.
Specific systems aside, Mellencamp says that carbon filters are generally a good place to start with under-sink filtration. “Most filters on the market use carbon filtration technology to trap contaminants inside your filter, preventing them from flowing through your tap,” he says. Sold? Keep reading to uncover five highly-rated under-sink water filters.
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For more information please see the list of Best under the sink water filters