How Long Does Bottled Water Last? | Build a Stash

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Key Takeaways

  • While water has no expiration date, bottled drinking water will “go bad” over time.
  • Chemicals in the water bottles can contaminate it if left for too long.
  • Store your unopened bottled water in a cool, dry, dark place for maximum shelf life.
  • Other alternatives include purchasing alkaline water or storing in aluminum bottles.

If water never goes bad, then why do commercial water bottles have expiration dates for consumers? How long does bottled water last?

While bottled water itself does not technically have an expiration date, the reason to avoid drinking “expired” bottled water is that the chemicals present in the bottles themselves will enter the water and make it contaminated. This is what makes bottled water go bad.

We’ll look at the reasons to consider the “expiration date” of water stored in plastic bottles, and how you can use some simple tips for storing bottled water to make it last longer.

Table of contents


How Long Does Bottled Water Last?

Sometimes you may see an expiration date on regular bottled water and wonder, “Why do they put the date on the bottle if water never expires?” In theory, bottled water should be safe to drink forever, since water does not spoil like other foods.

The FDA (Food and Drug Administration) doesn’t even require a printed expiry date on bottled water, although most manufacturers still print one as a consideration for consumers.

That being said, most companies will print an expiration date of two years from manufacture. This is a comfortable average time that allows the consumer to drink from the bottle at its best quality, and provides enough of a warning for bottled water that might be beyond its useful shelf life.

What Makes Bottled Water Expire?

The short answer is that, while the water itself never expires, the chemicals used in most retail bottles will eventually leach out into the water over time.

One of the main components of single-use water bottles is polyethylene terephthalate (PET), and larger water cooler jugs are made with high density polyethylene (HDPE). These and other chemical compounds are toxic to the human body, and your water will eventually be exposed to these chemicals once the plastic begins to break down.

Furthermore, plastic itself is naturally porous, no matter what its original quality. As it degrades over time, it will also be exposed to compounds from other nearby sources, including household chemicals and other dangerous substances that may be stored nearby.

The toxins and chemicals that water can absorb can compromise your immune system and even cause neurological problems. The effects won’t be immediate, but the cumulative effect of this health hazard is enough to warrant making changes to how we think about drinking “expired water” from plastic bottles.

All of this will not only affect the taste of water, but also introduce harmful elements that will hurt your body over time.

One of the main culprits for degrading the integrity of plastic water bottles is excessive heat, especially from direct sunlight. If you store water in hot cars or in some other area that is susceptible to overheating, this will accelerate the process of water bottles breaking down and leaching those chemicals into your water.

Making the Most of Bottled Water

If you drink water from a plastic bottle (like most people), you might be concerned if bottled water from plastic water bottles is safe to drink. You can take more drastic measures like eliminating plastic containers completely, but some simple strategies can keep your drinking water a bit safer.

Water Quality Can Make a Difference

You can always start with high quality water. Whether you take it with you in a reusable container or from water bottled commercially,starting with cleaner water will give you a little edge when thinking about its useful life.

Drinking from natural sources like spring water may not be cost-effective for people who are accustomed to using only tap water, but it is an option.

You could also switch to sparkling water, which some people prefer over still water. However, sparkling water can also be affected by the bottle it is stored in, and may lose its carbonation if left for too long - especially after it’s been opened.

Leave It Sealed as Long as Possible

In general, opened bottled water will expire sooner, since it is exposed to outside contaminants once it is no longer in an airtight or watertight container.

Using a reusable bottle or cup is also not the most reliable, since it is constantly opened and closed and refilled as needed. If not properly cleaned, you not only run the risk of dirtying up your clean drinking water from the chemicals in the cup, but also through cross-contamination due to contact with other substances.

Choose the Right Bottle, and Keep It Clean

You should always clean your reusable water bottle if you use one. A simple wash with tap water and an antibacterial cleanser will remove any surface debris and destroy most bacteria that could contaminate your water.

Some consumers are opting into the growing market of BPA-free plastic for reusable water bottles and cups. This removes the potential for some contaminants that could pollute your water, and they are generally not that much more expensive than more basic alternatives.

Another great option is to skip plastic altogether and go for aluminum bottles. Aluminum does not decay like plastic, and will generally have a much longer shelf life - sometimes up to 50 years as opposed to the much shorter two years for plastic.

Rotate Out Bottled Water

If you regularly store bottled water as an easy supply for yourself and your family, or if you hold onto stockpiles of bottled water in case of an emergency, just keep an eye on the expiration date printed on your bottled water.

A good rule of thumb would be to not drink expired water. It may not be a safe assumption that your bottled water remains uncompromised. When in doubt, either throw it out or use it for other purposes.

Extending the Shelf Life of Bottled Water

You can plan ahead now to ensure that your bottled water is properly stored. This will make your bottled water last as long as possible, so that it’s there when you need it most.

Remember that the biggest enemy of bottled water is heat. Keep your bottled water in a cool place that does not experience extreme swings in temperature.

A dry place is also essential for extending the usable life of your bottled water. Any outside moisture can compromise the bottle itself and seep into the water, affecting both its taste and its fitness for consumption.

Above all, leave it unopened. The seal on water products that are sold commercially must remain intact to keep your water safe from outside pollution as long as possible. Once that seal is broken, bacteria and other substances can find their way into your water and ruin your supply.

The Alternative of Alkaline Water

One more choice to consider is alkaline water. Water is alkaline, or basic, when its pH level is greater than seven (if it is less than seven, it is considered acidic). Water that is too alkaline may be unfit to drink, but alkaline water that has been produced using safe methods will generally last a bit longer than regular bottled water.