Is Purified Water the Same as Distilled Water?

It’s an easy assumption to make – both sound clean, both sound pure, so surely they’re more or less the same thing? Not quite. Purified water and distilled water are related, but they’re not identical, and the difference matters more than most people realise.

I spent a lot of time researching water quality before our family made the switch to distilled water back in 2018, and understanding the difference between purification methods was a big part of that process. Here’s what I found – and why we ended up where we did.

What is purified water?

Purified water is a broad term. It simply means water that has been treated to remove contaminants, but it doesn’t specify how that treatment was carried out. There are several different purification methods, and they vary significantly in what they actually remove.

Common purification methods include carbon filtration (what most filter jugs use), reverse osmosis, UV treatment, ion exchange, and distillation. All of these produce “purified” water to varying degrees – but they don’t all produce the same result.

So when you see “purified water” on a bottle or product, it tells you that something has been done to clean the water. It doesn’t tell you much about what’s actually been removed.

What is distilled water?

Distilled water is produced through a specific process – distillation. Water is heated until it turns to steam, the steam rises and passes through a cooling coil, condenses back into liquid, and drips out into a collection jug. Everything that was dissolved in the original water – minerals, chemicals, heavy metals, bacteria, and other contaminants – gets left behind in the boiling chamber.

The result is very pure water. When I tested our tap water with a TDS meter (Total Dissolved Solids), it measured 220 ppm. After distilling, it measured just 2 ppm. That’s not a small difference.

Distilled water is technically a type of purified water – distillation is one method of purification. But not all purified water is distilled, and that distinction matters.

So is purified water the same as distilled water?

No – but distilled water is a type of purified water.

Think of it this way. All distilled water is purified, but not all purified water is distilled. Purified water is the broad category. Distilled water is a specific, highly thorough method within that category.

The key difference is what gets removed. Carbon filters, for example, are good at removing chlorine and improving taste, but they don’t remove everything. Reverse osmosis removes more, but still not everything. Distillation removes virtually everything – minerals, chemicals, heavy metals, bacteria, and more. Traditional residential reverse osmosis systems typically waste three to four litres of water for every litre they produce, though newer models are more efficient.

Our experience with a filter jug

Before we switched to a water distiller, we used a filter jug – the kind you fill up and keep in the fridge. It made the water taste better than straight from the tap, which felt like progress at the time.

But the more I looked into it, the more questions I had. My first concern was trying to find out what the filter itself was actually made of – the physical materials inside it that our water was passing through every day. Back in 2018, that information was genuinely hard to come by. I searched and searched and couldn’t find a straight answer, and I found that deeply uncomfortable. If something is filtering the water your family drinks, you should be able to find out exactly what it’s made from without having to dig for it.

What I’ve since found out is that Brita filters contain ion exchange resin beads – small synthetic beads that swap out certain metal ions in the water – along with activated carbon granules made from coconut shells, and a polypropylene outer casing. The pitcher itself is made from styrene-based plastics. That information exists, but it certainly wasn’t prominent or easy to find when I was researching it, and the fact that our drinking water was passing through synthetic resin beads and styrene-based plastic housing every single day was not something I was comfortable with once I did find out.

And then when I dug into what a Brita filter actually removes, I found a whole other set of concerns. Standard Brita filters don’t remove bacteria, viruses, fluoride, pesticides, pharmaceuticals, or dissolved solids. A 2024 study published in Frontiers in Environmental Chemistry found that Brita Elite filters – their better model – only removed around 20% of PFAS chemicals on average. PFAS are the “forever chemicals” increasingly found in water supplies and linked to various health concerns. For a product marketed as a water purifier, that felt like a significant gap.

The combination of not being able to find out what the filter was made of, discovering it contained synthetic materials our water was passing through daily, and then finding out how much it was leaving in the water, made the decision to look elsewhere pretty straightforward.

Why we chose distillation

When I came across water distillers, a few things stood out.

The process made complete sense to me – boiling water into steam and condensing it back leaves everything behind. There’s no filter with unknown contents, no cartridge to replace that may or may not be doing what it claims. The science is straightforward, the results are measurable with a TDS meter, and you can see for yourself exactly what’s being left behind in the boiling chamber after each use.

It’s also cost effective over time. We were spending money on bottled water every week before – around 12 litres of it – and the filter jug cartridges weren’t free either. A water distiller has an upfront cost, but after that the running costs are minimal – just electricity and the occasional carbon filter for the spout. Over the years, it’s saved us a significant amount compared to what we were spending before.

And the results were immediately obvious. The water tasted cleaner and more neutral than anything we’d drunk before – filtered or bottled. Once you’ve tasted freshly distilled water, filtered water starts to taste like it still has something in it.

Which is better – purified or distilled water?

It depends on the purification method, but in my view distillation comes out on top for thoroughness.

Carbon filtration is better than nothing, but it’s limited in what it removes. Reverse osmosis is more thorough and a reasonable option, but it’s expensive to install, produces a lot of waste water, and still doesn’t remove everything. Distillation removes virtually all contaminants and gives you measurable, consistent results every time.

The one argument against distilled water you’ll often see is that it removes minerals too – including ones like calcium and magnesium that are present in tap water. This is true. But your body gets those minerals from food, not water, so for most people eating a normal varied diet this isn’t a meaningful concern. I’ve written about this in more detail in my post on whether distilled water is safe to drink.

What about reverse osmosis?

Reverse osmosis deserves a mention because it’s often compared to distillation as one of the more thorough purification methods. It forces water through a semi-permeable membrane that blocks most contaminants, and it does a good job – but it typically leaves some dissolved solids behind, uses a significant amount of water in the process (often wasting two to four litres for every litre it produces), and requires professional installation under your sink.

Distillation is simpler, more measurable, and in my experience produces consistently purer results. For a home setup, a countertop water distiller is far more accessible than a reverse osmosis system.

Making distilled water at home

If this has you thinking about trying distilled water, it’s much easier to produce at home than most people expect. A countertop water distiller – we use the Megahome, which has been running in our kitchen since 2018 – sits on your worktop, fills with tap water, and produces around four litres of pure distilled water in about four hours.

You can read more about how to make distilled water at home and the benefits of drinking distilled water if you want the full picture of why we made the switch and have never looked back.

The bottom line

Purified water and distilled water aren’t the same thing. Purified is a broad term covering many different methods with very different results. Distilled water is a specific, highly thorough process that removes virtually everything from the water – and produces consistently pure, measurable results.

We started with a filter jug, questioned what it was actually doing, couldn’t get clear answers, and ended up with a water distiller. Seven years later, it’s one of the best changes we’ve made for our family’s health and our household routine.

If you’re curious about why I drink distilled water and what prompted the switch in the first place, that post goes into the full story in more detail.