The Waterdrop Reverse Osmosis Instant Hot Water Dispenser System might be a fair bit more expensive than the average under-sink water filter on the list—but it’s well worth the extra money if you’re looking for additional features. The tankless water filtration system offers an innovative design that can provide both cold and hot water depending on your specific needs.

The Waterdrop TSA 8 is a great value system that still maintains an efficient filtration process, making it a good option for those who want to filter their water without breaking the bank.

Our engineers found that Waterdrop's tankless design saves space compared with traditional reverse osmosis (RO) systems and is more efficient too.
The Waterdrop is NSF 58 certified, one of the highest standards, so it can stand up to everything from heavy metals to pharmaceuticals to PFAS.

A Smart System That Keeps You Updated On Filtration Featuring a tankless design, this Waterdrop system takes up less space under your sink than most reverse osmosis systems, making it a great pick for those with smaller cabinets. This system also comes with a brushed nickel faucet that has a monitoring panel, which displays the quality of your water and tells you when it’s time to change the filter.