How CR Tests Water Filters
We test water filter pitchers by timing how long it takes the pitcher to finish filtering 1Ā quart of water at multiple intervals until weāve gone through up to 40Ā gallons of water, the typical life of this type of water filter. We also measure whether a filterās flow rate slows down (gets clogged) over the course of the cartridgeās capacity and, if so, by how much.
If a manufacturer claims a pitcher meets NSF/ANSI standards for removing specific contaminants, such as chlorine and lead, we verify each claim. NSF International and the American National Standards Institute develop filtration standards.
We also check claims of flavor and odor reduction by spiking water with commonly found compounds that can make water smell and taste like a sewage treatment plant, damp soil, metal, and a swimming pool. A trained panel of professional tasters evaluates how successful the filters are at removing these flavors and odors.
An Excellent rating means that most people wouldnāt be able to discern a palatable difference between the filtered water and pure spring water. A score of Fair or Poor means you will probably be able to tell the difference.
We test under-sink filters by measuringĀ how effectively they remove flavor and odor taints from a CR-created "control water" sample. Then weĀ examine how close that control water compares with regular filtered water. We determine the flow rate byĀ the time it takes to filter 1 quart of water, and clogging reflects whether and how the filterās flow rate slowed over the course of a cartridgeās lifespan. We also verify under-sink filter claims of lead and chlorine removal.
What's in Your Water?
The Environmental Protection Agency requires community water suppliers to provide a Consumer Confidence Report to customers every July. A CCR states the levels of contaminants detected in the water and how they compare with the EPAās drinking water standards. If you rent an apartment, contact your building manager or local water company for a copy.
Community water systems providing water to 100,000 or more people must post the reports online. If youāre on well water, you wonāt have a CCR because the EPA doesnāt regulate private wells. In that case, check with theĀ Centers for Disease Control and PreventionĀ for information on testing and treatment.
The water quality report tells you about the water in your municipality, but if your home was built before lead-free pipes were mandated in 1986, a test is the best way to assess the quality of the water coming out of your faucets at home. Thereās no safe level of lead exposure, according to theĀ EPA.
In the CR-Guardian study, almost every test sample had measurable levels of PFAS, which are linked to cancer, learning delays in children, and thyroid disease. More than 35 percent exceeded the maximum safety threshold specified by CR scientists and other health experts.
PFAS, found in hundreds of household products, are a growing concern. At least 2,337 communities in 49 states have drinking waterĀ contaminated with PFAS, according to a January analysis by the Environmental Working Group, an advocacy organization. Thus far, the EPA hasnāt set an enforceable legal limit for PFAS in drinking water.
Your state or local health department might offer free water test kits, and test kits are sold at home improvement stores. The EPA recommends sending samples to a certified lab for analysis. Your local water authority can offer a list of labs. Or you can check theĀ EPAās listĀ or call the agencyās Safe Drinking Water Hotline at 800-426-4791. For more on testing your water, see ourĀ interactive guide.
Fit the Filter to Your Needs
What a filter removes from water varies. Our water pitcher tests found that all models effectively remove chlorine and four models remove lead. All under-sink filters in CRāsĀ ratingsĀ meet the strict standard of lead and chlorine removal.Ā
Once you know whatās in your tap water, choose a filter that best suits your needs. Look at the pitcherās packaging for its contaminant removal certifications, if any. Third-party labs that certify products to NSF standards include the CSA Group, Underwriters Laboratories (UL), and the Water Quality Group (WQA), so you may see those certification seals, too.
All pitchers have filters that must be replaced periodically to function effectively. Check the specs in theĀ full view of our ratingsĀ to compare the costs of replacing filters for one year. For example, it ranges from $27 to $150 for the pitchers we test; youāll also see which models have a filter-life indicator, a handy feature that tells you when itās time to change the filter.
Use our water filter ratings to find the right water filter system for you. If youāre looking for a water filter pitcher, youāll find big differences in contaminant removal, flow rate, and clogging among the models.
Filtering Your Choices
Water filter pitchers are one of the most widely used choices, but there are other filtration systems available for the home. Factor in your budget, your water consumption, maintenance, and, most important, the contaminants found in your water before purchasing a new filter.
Water Filter Pitcher
The best model we tested did a stellar job of removing chlorine without sacrificing cartridge life or flow rate. Some others are slow, are prone to clogging, or have a short filter life. A small pitcher stored in the refrigerator might suffice for one or two people, but a large size may be more convenient for a family that consumes several gallons of water a day.
Price of tested filters: $17 to $85.
Faucet-Mounted Water Filter
If youāre looking for easy installation, these are a good choice for filtering drinking and cooking water. Simply unscrew the aerator from the threaded tip of the faucet and screw on the filter. Faucet-mounted filters let you switch between filtered and unfiltered water. On the downside, they slow down water flow and donāt fit on all faucets, including those with a pullout sprayer.
Countertop Water Filter
These filters are also easy to install: Just remove the faucet aerator, then screw the filter onto the faucet. This allows you to filter large quantities of water without modifying your plumbing. Countertop filters are less likely to clog than pitcher filters or faucet-mount filters. But they can clutter a countertop, and they donāt fit all faucets.
Under-Sink Water Filter
Like countertop filters, these can filter lots of water. Instead of cluttering the counter, they rob space from the cabinet beneath the sink. They may also require professional plumbing modifications and drilling a hole through the sink or countertop for the dispenser.
Reverse Osmosis Water Filter
Using standard household water pressure, water is forced through a semipermeable membrane, then through filters. Reverse osmosis filters can remove a wide range of contaminants, including dissolved solids. They can be extremely slow, rob cabinet space, and typically create 3 to 5 gallons of wastewater for every gallon filtered. You must sanitize them with bleach periodically, and the membrane and filters must be replaced, per manufacturerās recommendation.
Refrigerator Water Filter
Water-and-ice dispensers are common on bottom-freezer and side-by-side refrigerators. The water line typically runs through a built-in filter. Most filters can be easily replaced by simply pushing and twisting. A replacement filter costs about $50 or more, and youāll need to change it every six months or so. Depending on the particular filter, fridge filters can reduce many of the same contaminants as a countertop or undercounter filter.Ā
Consumer Reports is not currently testing refrigerator water filters
