Reverse osmosis filters water through a membrane under line pressure; distillation boils water and condenses the steam. Both produce low mineral water, but they fail on different things, run at very different speeds, and only one of them is practical as a plumbed household supply. That difference decides which belongs in your kitchen.
The two mechanisms, side by side
Reverse osmosis relies on pressure forcing water through a membrane whose pores reject most dissolved solids, sending the rejected fraction down a drain line continuously. Distillation relies on a phase change: water becomes vapor, leaves its dissolved salts and metals in the boiler, and condenses back to liquid in a cooled coil. One is a filter that never stops, the other is a batch process that empties and refills.
What each one misses
Distillation carries over anything that boils at or below the temperature of water and travels with the steam, which is why some volatile organic compounds survive it unless the still has a carbon vent stage. Reverse osmosis handles those poorly too if it lacks its carbon stages, but complete systems always include them. Neither is a reliable disinfection device on its own, and both depend on prefilters and membranes or boiler surfaces being kept clean to keep working.
Living with each in a real kitchen
An under sink reverse osmosis system fills a storage tank quietly and gives you a dedicated faucet, so water is simply there when you want it. A countertop still occupies a counter, runs a heating element for hours, produces a batch at a time and needs the boiler descaled by hand. For a household that wants low mineral water on tap for drinking, cooking and ice, the plumbed system is the one that gets used. Our reverse osmosis buying guide compares system sizes.
When the still is genuinely the right buy
Distillation earns its place where you need small volumes of very low mineral water and no plumbing: filling a humidifier or steam iron, topping up a battery, or a rental where you cannot cut into a supply line. It also needs no drain connection, which matters in apartments. Outside those cases, the running time and the manual descaling usually push a household back toward a membrane system.
Questions people ask about difference between ro and distilled water
Is RO water the same as distilled water?
No. Both are low in dissolved minerals, but they are made by different processes and reject different things, so the results are not interchangeable.
Which is purer, RO or distilled?
Distillation usually leaves fewer dissolved solids, but it can carry over volatile compounds that a carbon stage on an RO system captures.
Can I use RO water where distilled is specified?
Not always. Appliance and medical device makers specify distilled for a reason, and RO water still carries a small dissolved solids load.
Which costs less to run?
Reverse osmosis uses no electricity but sends water to the drain. A still uses no drain water but runs a heating element for hours per batch.