Best under-sink water filters of 2026

What each listing covers: Waterdrop is certified for chlorine only

A certifier listing names each substance a model passed in testing. A brand page names whatever the brand chooses. I matched each model number to the IAPMO, WQA and NSF listings on October 13, 2026, and the Pentair models on October 15, 2026. The filters here work with carbon, and how activated carbon filters work explains why chloramine needs its own line in a listing. Listings for other filter types are in NSF certified water filters.

The contaminants or other substances removed or reduced by this water treatment device are not necessarily in your water.

The Waterdrop gap is the one to know. Its product page lists heavy metals and shows “NSF/ANSI 42 & 372 certified.” NSF/ANSI 372 covers the lead content of the parts that touch water, not what the filter takes out of it. The IAPMO listing for the 10UA and 15UA names chlorine, taste and odor, and the review checks Waterdrop’s full lineup listing by listing. For lead, look at the Epic or either Aquasana.

LARQ's page lists lead and VOCs, but its NSF listing names total PFAS and chlorine. The Epic is the other way round: its listing covers lead and VOCs and no PFAS, and Epic's page doesn't claim PFAS either. Four of the picks are listed for lead and PFAS together: the two Aquasana models and the two Pentair models, whose PFAS claims sit in a separate IAPMO certificate. Of those four, only the Aquasana pair adds chloramine and VOCs. Outside the picks, NSF lists Brio's Premium under-sink filter for lead and total PFAS in the same NSF/ANSI 53 listing, with VOCs and cysts; see my Brio water filter review. Every type we track with a lead listing under NSF/ANSI 53, from pitchers to faucet mounts and RO, is in lead-certified filters.

Your faucet or a second one: 0.5 to 1.5 gpm

Seven of the nine connect to the cold-water line under the sink and send filtered water out of the faucet you already have. There is nothing to drill, which suits renters, and my water filters for apartments sorts the options by what each needs to install. Epic puts its install at 15 to 20 minutes with an adjustable wrench and a screwdriver, and LARQ at about 15 minutes. Both are brand figures. Hot water bypasses the filter, which is fine: you drink and cook with cold. Outside the picks, Kohler's Aquifer cartridges and A. O. Smith's direct connect filters install the same way. They are covered in my reviews of Kohler Aquifer filters and of the AO Smith water filter range. If you would rather not work under the sink at all, faucet water filters attach to the spout in place of the aerator.

The Claryum 3-Stage and the Pentair F2000 are the exceptions. Each has its own small faucet next to your main one, so the sink needs a free hole, or you drill one. In return, the main faucet keeps its full pressure for dishes.

Flow is the other trade-off. The listings give 1.5 gpm for the Direct Connect, 1.4 for the Pentair Easy Flow, 1.25 for the Epic, 1.05 for the LARQ, 0.75 for both Waterdrop models and 0.6 for the F2000. Pentair says the Easy Flow reaches 2.2 gpm, a figure the listing doesn't back. Aquasana's data sheet gives 0.5 gpm for the 3-Stage. At 1.5 gpm a gallon pot fills in about 40 seconds. At 0.5 gpm it takes two minutes. Clearly Filtered does not state a flow rate.

Not independently measured: I have not yet found an independent flow or lab test of these nine filters that I could cite. The figures above come from the certifiers and the brands.

Cartridges per year: $18 to $455

The purchase price is only part of it. I added up the replacement cartridges at the brand's own prices, using the rated life, gallons or months, whichever comes first.

The Waterdrop 15UA is the cheapest to run because its cartridge is rated for 24 months. The Aquasana and LARQ cartridges have a 6-month limit, so you buy two a year even if a two-person kitchen never reaches the gallon rating. Their subscriptions take the price down, as shown in the table. Clearly Filtered replaces all three of its filters at once, every 9 to 15 months depending on household size. Both Pentair models change filters once a year, but the F2000 pair is rated for only 675 gallons, so a family that cooks with it will change it sooner.

Warranties: 3 years limited on the Epic, 1 year limited on both Aquasana models, 1 year limited on the LARQ, 1 year on the Waterdrop and Pentair models and a 2-year limited warranty from Clearly Filtered. Returns run 90 days at Aquasana and 30 days at the others. Epic gives its subscribers 60, and LARQ takes the filter back only unused.

When you need reverse osmosis instead

None of the listings above names fluoride, arsenic, nitrate or TDS. In the reverse osmosis listings I checked, those sit under NSF/ANSI 58, the standard for RO systems. Aquasana's own FAQ says the Direct Connect does not reduce fluoride. Clearly Filtered is the only filter here that claims fluoride, and no listing backs that claim.

So the choice follows your water report or a home water test. If it shows lead, PFOA/PFOS or a chlorine taste, a carbon filter from this page can cover it, and it sends no water to the drain. If it shows fluoride, arsenic, nitrate or high TDS, look at the reverse osmosis systems listed under NSF/ANSI 58. If a membrane, a tank and a drain line are new to you, start with what reverse osmosis is.