Good To Know: What Is The Difference Between Distilled Water And Purified Water?

There are a dizzying array of waters on the market - purified water, spring water, filtered water, distilled water. The labels seem endless!

It can be hard to decide which to use.

Luckily, we're here to help you understand the two most popular kinds: distilled water and purified water.

We’ll help you conquer the grocery aisle by discussing what those terms mean, comparing the two types of water, and exploring how they're each used. With our assistance you'll have no problem knowing what is the difference between distilled water and purified water.

Is distilled water the same as purified water?

purified water

It probably sounds like purified water and distilled water are the same. But they're not.

Recall, there are many ways to purify water and that their final products are a bit different. Distilled water has been purified, but not all purified water has gone through the distillation process.

What that means is that they can't necessarily be used interchangeably.

Purified water versus distilled water.

Purified water and distilled water are similar; they have a few things in common:

  • Both have very few impurities.
  • Both are safe for humans and pets drink.
  • You'll find both types of water bottled and sold commercially.
  • Both can be used in most household applications.
  • Water quality of both is closely monitored.

But they have a few key differences:

  • There are many ways to purify water, but only one method to distill.
  • Purified water may have residual mineral deposits; but distilled water will not.
  • Distilled water is used in more technical applications than purified water.
  • Purified water generally involves a filtration method only.
  • Distilled water is tasteless but purified water is not.

It's because of those differences that they have some specific uses.

How you use distilled or purified water?

Purified water and distilled water both have several uses besides just drinking.

Purified water is often used in cooking if you're unhappy with the quality of your tap water or have old plumbing. Household plumbing can add germs and minerals deposits to tap water so people install home-purification units for extra protection.

purified water

Purified water is often used in gardening to control the chemical composition and pH of soil; some plants are very sensitive to chlorine found in tap water.

Distilled water is almost exclusively used in laboratory and hospital settings because it doesn't affect sensitive equipment or interfere with test results. Autoclaves, machines that use super-heat and pressure to sterilize equipment, require distilled water for proper maintenance. Minerals and chemicals in other waters don't produce clean enough steam.

It's also used at home when making baby formula because babies' digestive and immune systems are still developing. Using distilled water controls the mineral content and pH of what's being ingested by baby.

Your vehicle's cooling system relies on distilled water to prevent deposits from clogging and corroding internal parts.

What is purification and distillation?

All publicly available water is purified, including tap water. Purification is a process that removes one or more impurities from the water. The impurities could be:

  • Physical – This includes things like sand and debris.
  • Chemical – These impurities include pesticides, road runoff, and detergents.
  • Biological – This includes bacteria, parasites, and other pathogens.

What impurities exist depends on the water’s source. For example, ocean water contains different contaminants than sewer water. And lake water would have a different profile than both.

 is distilled water the same as purified water

Several different purification methods exist. Each method removes a different kind and quantity of impurity. Government agencies regulate the standard water quality achieved, but we're looking at the magnitude of micrograms of solids per liter of water. So, incredibly small amounts.

The method used depends on your available equipment, finances, and expected product. Some processes specialized materials and equipment that are prohibitive for household use but most have household version. Other methods may only be used in emergency situations or while outdoors.

These methods include:


This involves using a membrane to catch solid contaminants. The membrane, called a filtrate, consists of several layers of material sandwiched together. Each layer has holes that allow water to pass through. Items bigger than the holes get stuck on the filter.

distilled or purified water

The quality of the final water product depends on the kind of filter present. Some simple filters only remove large particles like sand, while other more advanced filters can remove some chemicals. Usually the layers of the filtrate have increasingly smaller holes so that the fluid becomes more filtered as it passes through.

Water quality also depends on how clean the filter is. Filters will need to be changed more often when used with very contaminated water.

Filtration methods are used in camping, water treatment facilities. What differs is the type and scope of filter used. Campers often carry handheld filters to clean water before drinking from streams and lakes. Filtration is also one of the first steps public water goes through. It removes everything from large trash to small particles of sand.


This purification method involves heating a source liquid to a boil and then capturing the resulting steam.

purified water vs distilled water

Distillation works because the components of the source liquid all have different boiling points, thus creating steam at different temperatures. Very light, non-dense chemicals boil and steam at lower temperatures than heavy dense chemicals. The steam is captured in a separate container then cooled to condense back into liquid.

It's seen a lot in oil refineries and when making spirits.

Oil refineries use distillation to separate crude oil into components such as gasoline, paraffin, and asphalt. Gasoline has a very low boiling point and separates from the crude oil very fast. It's low boiling point is also what makes it useful as automobile fuel. Asphalt has a very high boiling point; this is what allows it tutu start solid on the roads even during the sunniest of days.

Spirits are distilled beverages made from fermented fruit, grains, or vegetables. The materials ferment into a mash of solids and liquids. The mash is heated so that it produces steam. Alcohol has a lower boiling point than water, and than the solids. That alcoholic steam is collected then processed into the liquors we know as rum, vodka, and whiskey.


This is one of the oldest, most well known ways of purifying water. Boiling works because heat kills the microbes that make you sick.

purified water versus distilled water

Things like parasites, bacteria, and algae are what make people and animals sick. Prolonged heat from boiling kills them so water has to be heated to a rolling boil for approximately ten minutes for this to work. It's commonly used in emergency and outdoor situations.

The drawback, though, is that boiling doesn’t remove any sediment. It's usually combined with other filtration methods to achieve optimum water quality.

Granular Activated Carbon (GAC) filtering

GAC filtering is known better as “charcoal filtering.” This process uses activated charcoal to remove soluble and insoluble contaminants.

The pieces of activated carbon, or charcoal, physically and chemically remove particles from the water. Debris obviously gets trapped between the pieces, but microscopic debris gets caught in the pores of the material. Additionally, the carbon reacts with many odor-causing chemicals causing them to neutralize and no longer smell.

the difference between distilled water and purified water

Many different granules exist to accommodate the array of systems. Granules can be made from a variety of substances including coconut shells. Each granule had a different pore size and carbon content that enables it to filter specific impurities. Easy access and variety of supplies is what makes GAC filtering so widely used in household and aquarium filters.

GAC filters need to be changed regularly but how often depends on starting water quality and how frequently the filter gets used. Heavily used filters with high contamination levels will require more frequent changes than one used with clean water.

Reverse osmosis

Reverse osmosis, also known simply by acronym RO, is like filtration in that it involves source water going through a membrane. Where it differs is how the water is moved through, and what kind of purification is taking place.

purified versus distilled

Other filtration systems allow water to flow freely through the filtrate or membrane. That's not the case in an RO system. Reverse osmosis involves forcefully pushing the source water through a membrane. Doing so removes charged particles called ions from the water. Charged particles are substances like chlorine and sodium.

This process involves multiple stages of specialized tanks and coils. It's most commonly used in industrial desalination plants that turn sea water into freshwater. Household units that remove chlorine have become available as technology advances and supplies become less expensive. Household RO systems tend to be less efficient than other purification methods. That is, they produce lots of excess wastewater.


This process uses naturally-occurring organisms to breakdown pollutants into less toxic substances. The organisms are usually fungus or bacteria.

Sewer treatment plants and septic systems are the most popular forms of bioremediation. In both cases the source water is full of nitrates and sulphides from human waste and other pollution. Fungus and bacteria thrive in such environments.

The organisms can either be added to the source material, or simply encouraged to grow faster. In either case they use the nitrates and sulphides a food source. In turn, those chemicals are rendered harmless to the environment and people.

distilled or purified

Bioremediation is fairly inexpensive. It's also considered environmentally friendly, thus publicly accepted. But it's slower than other purification methods and requires specific mixtures of organisms. There's also concern with microbe overgrowth, and what to do with the bacterial sludge that sometimes remains.

It important to note that not all compounds can removed through this process. Though it’s good at removing nitrates and sulphides, it's not good at removing heavy metals such as lead.

As you see, distillation is one of the ways that water is made safe to drink.

Distillation removes physical, chemical, and biological impurities using heat. It works by collecting the steam of boiling water then condensing it back into a fluid. Heat kills the biological impurities. Physical impurities remain in the initial container because they are too heavy to rise in the steam. Chemical contaminants remain in the initial container because they have a different boiling point than water. The steam rises into a sterile collection bin where it cools back into fresh water.

Which is better to drink?

In conclusion, distilled water and purified water are equally safe and effective to drink. Purified water tends to be less expensive and contains minerals that your body needs anyway. Removing those minerals isn't necessary to maintain health so distilled water can be used only when certain circumstances need to be met. But if you don't like the taste of purified water, or just don't want the minerals, then it's okay to drink distilled water, too.