What contaminants affect your drinking water? Not all water is the same, and it's important to know what contaminants are present in the drinking water in your area. This will help you determine whether you need only a basic filter to improve taste or a sophisticated system that reduces pollutants and parasites. More information on your local water supply and how to find a state-certified tester can be found at the United States Environmental Protection Agency website. Once you pinpoint your specific water concerns, you can identify the best water filters for your needs.
How much water do you want to filter? If problems like sediment or sulfur are severe, you may want to consider a whole-house filter, although these won't remove all contaminants. If you need filtered water just for drinking, a pitcher may suffice. Cooks will find faucet-mount and under-sink filters more convenient as they won't need to continuously refill a carafe. Hard water won't be helped by a filter at all, for that you need a water softener.
How permanent do you want the water filter to be? Pitcher or faucet-mounted water filters are likely the best option for dorm residents or renters who can't make permanent modifications to their living spaces. Under-sink water filters are permanent and may require you to drill a hole for the filter faucet. These may require a certain level of expertise to install, which could necessitate hiring a plumbing professional.
Consider annual cost and maintenance requirements. Water-filtering pitchers and faucet-mounted filters aren't that expensive, but the cost of replacement filters will quickly outpace the initial purchase price. Use the cost of replacement filters and manufacturer recommendations on filter life to estimate your annual expenses. Cleaning, battery replacement and new semi-permeable membranes are additional charges for reverse osmosis systems. Also, consider the cost of discarded waste water if your supply is limited or you have high municipal water rates.
Elsewhere in this report:
Best-reviewed water filters: Whether you just want better tasting drinking water, or need to purify your entire water supply, these are the best water filters for improving water clarity, taste and safety.
Best water filter pitchers: A water filter pitcher gives you a supply of cold, filtered water in your fridge at all times. They come in a wide range of sizes and are affordable and easy to use.
Best faucet water filters: Countertop and faucet-mounted water filters give you unlimited amounts of filtered water without a permanent installation; these are the best, easiest to install faucet water filters.
Best under-sink water filters: Water filters that install under the sink filter out more contaminants and particulates than most other types of filters; reverse osmosis filters are even more purifying.
Best whole house water treatments: If you need to treat your water problems at the source, whole house water treatment systems are the best choice. We discuss both water filters and water softeners.
Our Sources: These are the expert and user reviews and recommendations we used to find the best water filters. They are ranked in order of credibility and usefulness.