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The Best Countertop Reverse Osmosis Systems

Reverse osmosis with no plumbing, for renters and anyone who'd rather not drill.

By Ice & Water Report Editors · Updated November 6, 2026 · 4 min read

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A countertop RO system gives you reverse osmosis water with no drilling, no plumbing and nothing under the sink. That makes it the answer for renters and anyone who doesn't want to touch the water line.

No. 1Best countertop RO

AquaTru Classic

AquaTru Classic
Price
$475 list
Type
0.75 gal clean tank
Gallons per day
Batch
Pure to drain
4:1 (claimed)
Certified to
NSF/ANSI 42, 53, 58, 401
Power
Needs an outlet

The AquaTru Classic is the countertop system we'd buy. You fill the tap-water tank, it runs the water through four stages, and clean water collects in a 0.75-gallon tank you can lift out and put in the fridge. It's certified to NSF/ANSI 42, 53, 58 and 401, and AquaTru claims a 4:1 ratio, far less waste than most under-sink systems.

It costs $475 list. It uses counter space and makes water in batches, so a large family may find themselves refilling it often.

What we like

  • No installation
  • Certified to NSF/ANSI 42, 53, 58 and 401
  • Low waste (4:1 claimed)

What to know

  • 0.75-gallon clean tank
  • Uses counter space
  • Needs an outlet

Countertop or under-sink?

Countertop (AquaTru)Under-sink (G3P800)
InstallNoneUnder the sink, drill for faucet
CapacityBatches, 0.75 gal clean tank800 GPD on demand
Best forRenters, one or two peopleOwners, families
Price$475 list$999 list

Compare them in detail in Waterdrop G3P800 vs AquaTru.

Questions

Can I fill an ice maker from a countertop RO system?

Yes. Pour from the clean-water tank into the ice maker's reservoir.

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