Is Demineralised Water the Same as Distilled Water?

Demineralised vs Distilled Water: What’s the Difference?

Water classification can be confusing. Two terms often used interchangeably are “distilled” and “demineralised” (DM water) — yet they are not the same thing. Understanding the difference is crucial: it determines whether the water is safe for your car battery, your medical equipment, or your drinking glass.

For a full guide on how distillation works and which distiller suits your needs, see our Water Distillers Guide. If you’re comparing purification methods, our Reverse Osmosis Guide is also worth reading.

What Is Demineralised (DM) Water?

Demineralised water has had its mineral ions — calcium, magnesium, sodium, sulfate — removed through ion exchange or membrane filtration. It’s effective at removing dissolved ionic minerals, but it does not reliably remove bacteria, viruses, or organic contaminants. This is the key distinction.

Common uses: industrial machinery, car batteries and radiators, steam irons, aquariums.

Safe to drink? Not recommended — it’s not sterile and lacks the purity of distilled water.

What Is Distilled Water?

Distillation is a physical process — water is boiled into steam, then condensed back into liquid in a clean container. Because contaminants don’t evaporate with the water, virtually everything is left behind: minerals, bacteria, viruses, heavy metals, and organic compounds.

Common uses: medical procedures, CPAP machines, laboratory experiments, drinking (with remineralisation).

Safe to drink? Yes — but for long-term daily use, remineralisation is recommended to restore beneficial minerals.

Browse our water distiller range for home distillation options.

Side-by-Side Comparison

Which Should You Choose for Drinking?

For drinking water at home, distilled water from a quality home distiller is the safer and purer option. Pair it with a remineralisation stage (mineral stones or drops) to restore beneficial minerals for daily use.

Alternatively, a reverse osmosis system produces very high purity water with a built-in remineralisation stage in many models — a popular choice for Australian households wanting maximum purity without the distillation process.

Frequently Asked Questions