Does Distilled Water Go Bad? 5 Signs To Watch Out For

If you’re wondering does distilled water go bad, you’ve come to the right place! Distilled water goes through many stages of purification, which may lead to the opinion that its shelf life is infinite. However, let’s find out if this is actually the case!

Quick Answer

Distilled water is subject to going bad when poorly stored. Several elements can render your efforts to store distilled water futile. They include:

  • Preserve the water in a contaminated container;
  • Exposing distilled water to direct sunlight;
  • Improper choice of storage container material.

But that’s not all! Keep reading to find out more reasons why your water may be spoiled, signs that your water is bad, the dangers of drinking spoiled water, and more!

Does Distilled Water Go Bad?

There is an opinion that distilled water has an infinite shelf life, but it is not true. Let’s get to the bottom of it and start with what distilled water means.

Distilled Water

Distilled water has gone through the processes involving boiling condensation and collecting to purify it. This process ensures that it is mineral salts and dissolved mineral-free. Compared to other forms of water, distilled water is crystal pure.

But, unfortunately, distilled water can spoil and become unusable. If expired water is used, it can lead to dangerous consequences such as allergic reactions, heart disease, kidney failure, and poisoning.

 Does Distilled Water Go Bad?

Some of the Reasons Why Distilled Water Can Go Bad

One of the most significant contributing factors to whether your purified water goes bad is how well you store it. Proper storage goes a long way in shielding distilled water from environmental influences such as:

  • Sunlight;
  • Temperature;
  • Air pollution.
Why Distilled Water Can Go Bad

Not shielding distilled water from these conditions will translate into the preserved substance being attacked by chemicals, thus resulting in contamination. These contaminants affect your water’s overall quality, making its use questionable.

Note: To prevent this, you must properly seal your containers.

How Long Does Distilled Water Last?

Does distilled water go bad and does it have a shelf life? Let’s look at its storage period from the type of water and its purpose:




Unopened bottle distilled water

More than two years

More than three years

Household distilled

drinking water

One week

Week and a half

Opened store distilled

water for drinking 

A few days to a week

Six to eight days

Opened, for appliance use

More than a year

More than a year and a half

Distilled Water Has Gone Bad: 5 Signs To Keep an Eye On!

Several indicators implicate bad distilled water. Some of them may take a longer time to show while others will catch your eye quickly after a short period. Let’s review some of these indicators!

Distilled Water Has Gone Bad: 5 Signs To Keep an Eye On

1. Unusual Odor or Taste

When you taste distilled water and encounter an unfamiliar and odd taste, that could indicate that some impurities made their way to the water. Because, unlike tap water, purified water has no taste due to its lack of additives.

As I mentioned before storing plays a huge role in the safety of distilled water. Let’s take a look in detail:

  • Opened container: If the storage plastic container is not correctly sealed, the stored water could be exposed to air, which carries various contaminants.
  • Direct sunlight and extreme temperatures: Exposing distilled water to extreme temperatures or direct sunlight for extended periods may stimulate bacterial growth, contaminating it.

2. Color Changes

When you store distilled water properly, it should remain discolored. So, if you encounter a different color of water, have any sign of temperance with the transparency indicating that the water is no longer pure.

Color changes may happen to your bottled water due to several circumstances:

Color Changes
  • Chemical reactions: Besides environmental influences, chemical reactions in the atmosphere may cause visible changes. For instance, contact with certain materials like copper and iron may form a reddish or brownish residue.
  • Mineral residue: While the distillation process is supposed to filter minerals from water completely, some may slide through. With time, these sediments may tamper with the state of the water, causing spoilage.

3. Mold or Algae Growth

When exposed to certain conditions encouraging the proliferation of these microorganisms, such as exposure to direct sunlight, mold, and algae may begin growing. Preserving distilled water in a clear and transparent vessel in sunlight provides all the conditions encouraging these organisms’ sustainability.

Algae, mainly, are more likely to grow, forming a greenish or brownish formation. To prevent this:

  • Keep water away from direct sunlight: Store bottled distilled water in a place that shields it from sunlight, especially if the bottle is transparent.
  • Choose cold storage space: Molds and algae thrive in warmer environments. Therefore, placing distilled water in cooler areas is advisable to minimize the risks of these bacteria forming.
  • Don’t forget about container tightness: Additionally, ensuring your container is sealed airtight prevents microscopic molds in the air from accessing your distilled water.

4. Visible Sediment

Sometimes, solid particles settle at the container’s bottom or float in your distilled water. These sediments clear to the naked eye clearly indicate that your water is no longer safe for consumption. These particles are evident in the water due to several contributing factors:

  • This could be a fault in the distillation process, allowing some particles to go through during the collection process.
  • The quality of the water source may also be part of the reason for the sediments.
Visible Sediment

Luckily, if you are experiencing this problem, filtering is the quickest way to fix it. Since they are solid particles can easily be separated from pure distilled water since they are solid particles.

Important! However, if you still feel an aftertaste after filtering, it would be best to dispose of the contaminated distilled water or employ it for other functions.

5. Container Contamination

Another critical factor in determining the sustainability of your distilled water is the storage unit. Before storing distilled water, you should make sure the container you intend to put it in is clean and bereft of any contamination residue.

  • Don’t use the container after hazardous substances: It is essential to check whether it was previously used for storing hazardous material. If so, you can thoroughly clean and use it. If not, purchase a new container.
  • Choose proper container material: Confirm the material of your container is sustainable enough to ensure the safety of distilled water. The best choice to go with would be glass bottles. These materials don’t support the leeching of bacteria, instead of metallic, plastic, or rubber containers.

What Are The 3 Major Dangers Of Drinking Contaminated Distilled Water?

Regularly drinking distilled water, is very justifiable. However, it may birth serious problems if contaminated. Contaminated water is not safe for your overall health. Let’s look at some dangers you are exposed to when consuming impure water!

What Are The 3 Major Dangers Of Drinking Contaminated Distilled Water

1. Microbial Impurity

Consuming impure distilled water means taking in water with microorganisms and harmful bacteria. These organisms may pose several challenges to your immunity as you will likely suffer from bacterial infections.

Before consuming drink distilled water, it is advisable you conduct your due diligence to ensure that the water you are consuming is safe.

Note: The best solution is to store distilled water properly or purchase bottled water.

2. Allergic Reactions

In most cases, water-related allergies aren’t usually directly correlated with the water itself but rather the contaminated substances. Water that wasn’t stored in a tightly closed container can contain common allergens like:

  • Pollen;
  • Mold spores;
  • Animal dander.

Consumption of such water can lead to dangerous health consequences.

3. Chemical Contamination that Causes Disease

Reactions with chemical components in the air may lead to the contamination of distilled water. Consuming this may stimulate some diseases because these chemicals are unsuitable for drinking.

The effects experienced can range from acute, short-term illnesses to chronic, long-term diseases. These effects will depend on the type and concentration of the chemicals involved.

Is Expired Distilled Water Usable? 4 Applications Except Drinking Distilled Water

The beauty of bottled distilled water is that you can use it after the expiry date. If you store distilled water properly, it will remain safe. Let’s look at some of them.

4 Applications Except Drinking Distilled Water

1. Laboratory and Scientific Experiments

Distilled water is a critical component in conducting several laboratory procedures. Especially when dealing with various experiments involving dissection and observation.

  • Distilled water must be used to clean the specimen in the preparation of slides.
  • Using distilled water makes the specimen more clear and the cells more turgid.
  • Furthermore, it preserves the integrity of the specimen.

However, store it properly to ensure efficiency in its use.

2. Medical Procedures

Due to its high purity, distilled water is employed in numerous medical procedures:

  • Dressing wounds: When dressing wounds, the affected area may be cleaned using distilled water to remove the germs in the afflicted area.
  • Equipment sterilizing: Distilled water is widely employed when sterilizing surgical equipment, . Its lack of impurity makes it the most suitable component to get the job done.
  • Medicines diluting: Properly distilled and bottled water also plays an enormous role in diluting medicines.
Note: Some medicines are extremely concentrated and require some water to make them effective. In most scenarios, pharmacists provide an unopened distilled water bottle to help you mix.

3. Automotive Cooling Systems

In situations where maintaining the vehicle’s cooling system and preventing it from interacting with minerals is key, distilled water plays an important role.

  • When regulating the vehicle temperature, the standard element known as a coolant comprises water and antifreeze.
  • Combined with distilled water, antifreeze prevents freezing in cold weather and overheating on hot days.

4. Battery Maintenance

In older lead acid batteries, expired distilled water:

  • Can aid in balancing the electrolyte level in the battery.
  • Helps in cleaning the battery terminals.
  • It is a suitable solvent for cleaning this terminal without forming any irregularities on your gadget.


Does Distilled Water Really Expire?

Yes, distilled water does expire. However, exceeding the manufacturing date doesn’t make distilled water go bad. You can still drink properly stored distilled water because it has a long shelf life.

How Long Can Distilled Water Be Kept After Opening?

Distilled water can stay for up to 9-12 months after opening. However, you have to properly store-bought distilled water to prevent it from being distilled water has gone.

Distilled Water Can Stay for How Do You Keep Distilled Water Fresh?

To keep distilled water fresh, you must employ several tactics, like keeping it away from direct sunlight and ensuring it’s in a clean container to store water.

Do You Refrigerate Distilled Water After Opening?

Yes, you can refrigerate distilled water after breaking the seal to store it for a long time. When refrigerated, an opened bottle of distilled water can stay up to 9-12 months, while an unopened bottle can stay for over two years.


So the answer to the question: “Does distilled water go bad?” is Yes! Even despite proper shelf life, it can be spoiled. Several factors play a big role like exposure to direct sunlight, the type of material the water is preserved in, and the cleanliness of the storage unit.

Using contaminated water is risky, and drinking it, especially, may open you up to allergic reactions and poisoning. To ensure you preserve the integrity of your distilled water, you can employ tactics like ensuring it is in an airtight container and placed in a cool place.

If your water has no visible signs of unsuitability but has only expired, you can still use it, but not for drinking. For example, to service your vehicle’s cooling system or for batteries.

Amy Grant

Amy Grant has a degree in journalism and has worked as a freelance writer and author for many years. She is passionate about clean drinking water and has written many articles on this subject. Amy enjoys hiking and water skiing with her husband and is grateful to have the opportunity to help others learn more about the importance of clean drinking water.

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