How distillation works
A countertop distiller boils water, captures the steam, and condenses it back to liquid in a separate container. Because most contaminants cannot become steam at 100°C, they stay behind in the boiling chamber. Everything else in your water — minerals, salts, metals, fluoride, nitrates — is left as scale and residue you tip out.
This is the oldest water purification method still in domestic use, and it is worth appreciating what makes it different from every other technology on this site: distillation is subtractive by default. Filtration asks “what can this medium capture?” and the answer is always a list. Distillation asks “what can survive the phase change?” and the answer is almost nothing. It is not a filter with a very good contaminant list — it is a fundamentally different approach that starts from near-total removal.
Nothing wears out, because there is no medium to exhaust. A distiller works identically in year five as on day one, provided you descale it. It is the only domestic technology where performance does not silently decline with use — and given how many of the failures we document elsewhere are invisible ones, that is a genuine and underrated advantage.
What distillation removes
| Contaminant | Removed? | Why |
|---|---|---|
| Dissolved salts, hardness minerals | Yes — essentially completely | Non-volatile; cannot leave with the steam |
| Fluoride | Yes | One of only two domestic methods that reliably does, alongside RO |
| Nitrates | Yes | Non-volatile |
| Lead, heavy metals, arsenic | Yes | Non-volatile |
| PFAS | Largely yes | Non-volatile at boiling temperature |
| Bacteria, viruses, cysts | Yes | Boiling inactivates them; they cannot travel as steam |
| Sediment, turbidity | Yes | Left behind entirely |
| Chlorine | Partly — often carried over | Volatile: boils off and can re-condense with the water |
| VOCs, some pesticides and solvents | Often not | Volatile organics boil at or below water and follow the steam |
The bottom two rows are the important ones, and they are the exact opposite of what most people assume. Distillation’s weakness is volatile compounds — anything that evaporates as readily as water travels with it into the collection jug. This is why quality distillers include an activated carbon stage on the condensate: the carbon handles the volatiles the boiling process cannot. A distiller without a carbon post-filter has a real and specific gap, and it is the first thing to check.
Distillation vs reverse osmosis
These two are the only widely available domestic technologies that address dissolved contaminants comprehensively, so the comparison is the practical decision most buyers actually face.
| Distillation | Reverse osmosis | |
|---|---|---|
| Removal breadth | Near-total, except volatiles | Very broad, including many volatiles via carbon stages |
| Speed | Slow — hours per batch | Continuous, on demand |
| Energy | Significant — boiling every litre | Minimal or none |
| Water waste | None | Several litres discarded per litre produced |
| Consumables | Carbon sachets only; no membrane | Membrane and pre/post filters on schedule |
| Installation | None — plug in | Usually plumbed; WaterMark applies |
| Performance over time | Does not degrade | Declines as membrane ages — often invisibly |
The trade is essentially energy and patience versus wastewater and maintenance. A distiller suits a renter who cannot plumb anything, a household on bore or rain water with dissolved contaminant concerns, or anyone who wants verifiable results without depending on a consumable performing as claimed. RO suits households wanting volume and convenience.
The two standard objections
“Distilled water is dangerous because it has no minerals.” This claim circulates widely and overstates its case considerably. Drinking water is a minor contributor to mineral intake compared with food, and the World Health Organization’s guidance on demineralised water concerns populations relying on it as a sole long-term source, not a household drinking distilled water alongside a normal diet. It is fair to note that low-mineral water contributes nothing nutritionally and that some people mineralise it deliberately; it is not fair to call it unsafe.
“It tastes flat.” This one is true and worth taking seriously, because it is the most common reason distillers end up in cupboards. Taste in water comes largely from dissolved minerals and gases, and distillation removes both. Many people adapt; some never do. Adding a pinch of mineral salts or a remineralising cartridge addresses it, at the cost of reintroducing some of what you removed.
A practical point rarely mentioned in marketing: a distiller gives you a visible record of what was in your water. The scale and residue left in the boiling chamber after each batch is the dissolved load, made physical. No other domestic technology shows you its own work.
Our verdict on the evidence
Distillation is the most thorough domestic water treatment available and the least fashionable, and neither of those facts is an accident. The physics is uncontested, the performance does not decay, and it addresses dissolved contaminants that most filtration cannot touch. It is also slow, energy-hungry, and produces water many people find unpleasant — which is why the market has moved toward faster, more convenient technologies that do less.
Our position: distillation deserves serious consideration where dissolved contaminants matter and plumbing is not an option, and it is the honest answer for anyone who wants results that do not depend on a cartridge performing as advertised. Two caveats decide it. Confirm the unit has an activated carbon post-filter for volatile organics — without it, the gap is real. And be realistic about batch time and running cost before committing, because the technology asks more of you daily than any other on this site.
Primary sources: established physical principles of distillation and volatility; World Health Organization guidance on the nutritional aspects of demineralised drinking water; comparative domestic treatment technology characteristics. Reviewed August 2026. FilterOut sells nothing and takes no commissions — see who to trust for filter advice.
FAQ
Does distillation remove fluoride and PFAS?
Yes. Both are non-volatile and stay behind when the water boils off. Distillation and reverse osmosis are the only two widely available domestic methods that reliably address fluoride — carbon filtration does not.
Is distilled water safe to drink?
Yes, for normal household use alongside a normal diet. Drinking water is a minor contributor to mineral intake compared with food. WHO guidance on demineralised water addresses populations relying on it as a sole long-term source, not ordinary household use.
What does distillation not remove?
Volatile compounds — chlorine, VOCs and some pesticides and solvents evaporate with the water and can re-condense with it. This is why a distiller should include an activated carbon post-filter on the condensate.