Countertop RO Systems

Reverse osmosis that sits beside the sink. Fill-and-dispense or faucet-connected, no cabinet work.

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What to expect

  • Ships direct from the manufacturer

    Every order is packed and shipped by the brand that makes it. We submit your order to them within 2 business days.

  • Estimated delivery on product pages

    Brondell, Crystal Quest and Waterdrop product pages show a dated delivery window under the buy button before you order.

  • Returns by brand

    Each manufacturer sets its own return window and restocking fee. Check the terms for your brand before you order.

    Return terms by brand

  • Tracking as soon as it ships

    We email your tracking number within 1 business day of the shipment leaving the manufacturer.

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Find your fit

Which countertop RO system is right for you?

Common situations and where to start. Each line comes from the product’s own page.

Choose a fill-and-dispense unit. The Waterdrop C1S and K19 fill from the top and dispense reverse osmosis water with no installation.

See units that need no plumbing

The Waterdrop C1S is rated 400 gallons per day and holds 110 ounces of filtered water in its built-in tank.

See the Waterdrop C1S

The Waterdrop K19-SFK adds a remineralization stage after the membrane and connects to your faucet.

See the Waterdrop K19-SFK

The Waterdrop K19 Instant Hot dispenses reverse osmosis water and near-boiling water from one plug-in unit.

See the K19 Instant Hot

The Crystal Quest Countertop Reverse Osmosis System is a 12-stage unit rated 50 gallons per day at standard residential faucet pressure.

See the Crystal Quest Countertop RO
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Countertop reverse osmosis

Fill-and-dispense or faucet-connected

Rated capacity is the gallons-per-day rating.

Countertop Reverse Osmosis System Crystal Quest Countertop Reverse Osmosis System Waterdrop C1S Countertop CoreRO System Waterdrop Waterdrop C1S Countertop CoreRO System
Starting price$202.23$259.00
BrandCrystal QuestWaterdrop
Rated capacity50 GPD400 GPD
Stages126
Water tankBuilt-in tank, 110 oz
InstallationNo plumbing. Fill the reservoir and dispense.
Dimensions16" x 7" x 7"11.7" x 8.3" x 13.7"
ReturnsNot returnable (reverse osmosis system). Details30 days from delivery. No fee if like new. Details
View Crystal QuestView Waterdrop

How to choose a countertop RO system

A countertop reverse osmosis system does the same job as an under-sink unit, a membrane with pre-filters and post-filters, without opening the cabinet. Two designs are in this collection: fill-and-dispense units that hold water in a built-in tank and need no plumbing, and faucet-connected units fed from the kitchen tap. Rated outputs run from 50 GPD to 400 GPD, with 6 to 12 stages, from Waterdrop and Crystal Quest.

Who it is for

Renters, small kitchens, offices and anyone who wants reverse osmosis water without drilling a faucet hole or fitting a drain saddle. Fill-and-dispense units also suit a counter with no faucet nearby.

What to compare

  • Connection: fill-and-dispense (no plumbing) or faucet-connected (runs from the tap).
  • Capacity (GPD): the rated daily output, listed on each product page.
  • Tank size on fill-and-dispense units, in ounces, which sets how often you refill.
  • Stages: the product page lists what each stage contains, from the pre-filter to the post-filter.
  • Counter space and the height under your wall cabinets.
  • Replacement filters and membrane: interval and SKU on the product page.

Ships direct from the manufacturer.

Common questions

Faucet-connected units send reject water back to the sink through a small line. Fill-and-dispense units have no drain line; the product page explains how each model handles reject water.

Faucet-connected units run from the kitchen tap. Check the product page for the fitting your faucet needs; pull-out and sprayer faucets usually need an adapter.

The fill-and-dispense units. Fill the tank from the tap and the unit dispenses reverse osmosis water. The section "Which countertop RO system is right for you?" on this page links to them.

Several countertop units here list PFAS among the contaminants they reduce, and some are certified to NSF/ANSI 58. Claims are made model by model, so check the reduction list and certifications on each product page.

Systems in this collection currently range from about $200 to about $380 before shipping. Each product page shows the current price.