You may be wondering “can my distilled water go bad?”. Despite being the purest form of water, distilled water, like all water, can go bad and be unsafe to drink or use.
Water that is distilled is purified using the process of distillation. Through this process, the water is boiled. When cooled, the steam is collected and turned back into pure liquid H2O water.
Distilled water can have a longer shelf life than ordinary tap water because of its purity and lack of contaminants. This doesn’t necessarily make it the best choice for storing long-term for emergencies.
The most common use for distilled water is in humidifiers and other household appliances. I like to use distilled water in my steam iron to reduce mineral deposits.
Drinking distilled water is okay but not recommended long term due to the lack of minerals in the water.
Clean tap or spring water is superior to distilled water if drinking water is needed.
How Long Does Distilled Water Last?
Distilled water can theoretically have a longer shelf life than other water because it is the purest form. Unopened distilled water jugs will generally be safe to drink and use for several years beyond the best by date if stored in a cool, dry place away from direct sunlight.
By itself, water cannot go bad, but environmental factors can compromise the safety of the water. Store-bought distilled water in a plastic container can degrade over time. The degradation process may leech chemical contaminants into the water or allow other things in the water.
Distilled Water Shelf Life
| Refrigerated | Pantry | |
| Opened bottle of distilled water | 9-12 months | 3-7 days |
| Unopened bottle of distilled water | 2+ years | 2+ years |
Store distilled water in glass bottles that can last much longer because the glass bottles will not degrade.
Opened bottled water can go bad sooner than unopened containers. Opening the container exposes the water to air and potentially other contaminants.
Just because the container was opened doesn’t necessarily mean it will spoil, but water safety must be taken seriously. Waterborne illnesses like Giardia and Cryptosporidium can kill you.
Distilled Water Vs. Purified Water?
Purified water has been filtered to reduce contaminants and improve purity. It is not the same thing as distilled water.
Most purified water will contain more minerals and is less pure than distilled water.
Is It Safe To Drink Distilled Water?
Distilled water is generally safe, provided the water hasn’t gone bad or been contaminated.
If all you have is distilled water, it will be acceptable to drink
The main reason not to drink distilled water is it doesn’t contain essential minerals our bodies need. That is why drinking spring water or regular tap water is preferable.
Is Expired Distilled Water Safe to Use?
Distilled water past its best by date can still be safe to use if stored properly. If you are planning to drink purified water, be extra careful to ensure it hasn’t spoiled.
About a year is the best-by-date on most distilled water I’ve seen. I have drank bottled water years beyond its best by date. There were no water issues, but I noticed a slight plastic taste.
I wouldn’t recommend drinking distilled water well beyond its best by date, but if you must, you definitely can do so.
How do I Tell if Distilled Water has Gone bad?
It can be challenging to tell if water has gone bad. Waterborne pathogens can live in water that looks and smells completely fine.
I got e.coli from drinking contaminated bottled water during a military training exercise in 2013. The water looked, smelled, and tasted perfectly clean, and there was no sign the water contained e.coli bacteria. We only learned of the e.coli after using specialized water testing equipment.
If you have any doubt about the safety of your water, don’t risk drinking it.
If you’re in a dire situation, boiling water can kill most pathogens in water. Remember that boiling usually won’t remove hazardous chemicals from the water.
- Green Algae – Algae can grow in water if the water has been contaminated and the conditions are right. Water with algae will be a yellow or greenish color. You may also notice greenish sediment in the container.
- Cloudiness – If your water is cloudy, it can indicate contamination or pathogens. Avoid drinking murky distilled water.
- Unusual smell – Strange smells strongly suggest something is wrong with your water. Just because water smells good doesn’t mean it’s safe, but don’t drink it if it stinks.
- Chemical taste – Water with an unusual or chemical taste is an indication the distilled water is contaminated. It may be chemicals from the container breaking down or something else.
How to Safely Store Distilled Water
Storing distilled water long term is the same as storing normal water. For the most extended shelf life, it’s best to use containers designed for long-term water storage. Check out our post on the best water storage containers.
- Keep your water in a cool, dry place.
- Use the proper containers. Food-grade HDPE plastic containers are designed to safely store water long term.
- Avoid direct sunlight. The sunlight can cause algae growth and the plastic containers to degrade
- Keep away from odorous materials. Strong scents can permeate your water containers and contaminate the water.
- Keep lids secure. Tightly sealed lids will prevent air exposure and leakage.
FAQ
Is drinking distilled water safe?
Yes, it is safe to drink distilled water.
Can bacteria grow in distilled water?
Yes, bacteria can grow in distilled water if it is contaminated.
How long does distilled water last?
The best by date on most bottles of distilled water is about one year if it is unopened.
How long does distilled water last after being opened?
Opened distilled water can last a year or more if stored correctly. Be careful if you intend to drink it.
How do I extend the lifespan of distilled water?
Store it in a cool, dry place away from sunlight.
What are the risks of consuming contaminated distilled water?
Consuming contaminated water can cause death or severe illness from waterborne pathogens or other contaminants.
Does distilled water need to be refrigerated after opening?
If you want to drink distilled water, it should be refrigerated after opening. It does not need to be refrigerated if used for appliances.
Does distilled water have chlorine?
No, it is pure H2O.
