Does Water Go Bad?

We drink water every day, both tap water and bottled one. But still, every now and then you find a rogue bottle of water sitting in the pantry for who-knows-how-long. That’s when we ask: does bottled water go bad?

Or maybe you were wondering why some companies put a best-by date on their bottled water, and others don’t. Is the water from the latter ones somehow better, or what’s the deal here?

While we drink water multiple times a day, there are still at least a few things you might be not aware of. Perhaps you read an article somewhere about plastic leaking carcinogens if the bottle sits in a car. Or that freezing water can make it toxic somehow.

In this article, we go through storage, shelf life, and going bad of bottled water and similar products like sparkling, flavored, or vitamin water. If that’s something you’d like to learn a bit more about, read on.

Water drops
(credit: laszlo)

How To Store Water

I’m pretty sure you’re well aware of how to store water, but for the sake of completeness, I’m going to type it out here too.

You should store an unopened bottle of water in a cool and dry area. The pantry is probably the best choice, but a kitchen cabinet works too. That recommendation stays true for all kinds of bottled water out there, including flavored, vitamin, and carbonated. If you prefer to drink it cold, feel free to keep it in the fridge instead.

Once you open the bottle, first and foremost you need to remember to seal it tightly when not in use. Second, you can store a half-open bottle of plain old water at room temperature, but all other types are much better off in the fridge.

If you’re storing some tap water in case of emergency, use large bottles and change the water every month or so. It’s not like it’s going to spoil or anything, but tap water stored for a long time tends to taste quite bad.

One of the reasons you’re buying bottled water is probably because you find its taste better. And that means you don’t find tap water that appealing to begin with, hence the need to change it regularly.

Can You Freeze Water?

Yes, obviously, we all make some ice cubes from time to time, right?

You can also freeze water in the bottle it comes in, provided you first open it and pour some out.

Warning

Water expands when frozen, so putting an unopened bottle straight into the freezer will result in a disaster.

Also, plastic won’t leak any carcinogens to the water when frozen.

How Long Does Water Last

Let’s start with plain bottled water.

Putting a shelf life on bottled water is not required by the FDA. That’s why some producers add it, but other’s don’t. Many companies put a date on the label simply because people tend to trust food that comes with a date more. But as long as you handle the storage properly, the water should last pretty much indefinitely.

Once you open the bottle, it’s best to finish it within a few days. Over time it will absorb some carbon dioxide, and thus its taste will change. That’s why many sources recommend finishing the bottle within 3 days and actually refrigerating the bottle.

When it comes to all other types of water, like carbonated, flavored, or vitamin, the best-by date comes useful.

Of course, the water in an unopened bottle won’t go bad a week or a month past that date, but its taste might be altered. The carbonated water won’t be as sparkly as it used to be, flavored will lose some of its taste, and vitamin might not have the exact same nutritional profile as a fresh bottle does. So by and large, it’s best to drink these types of water within a few months of the date on the label.

When it comes to the shelf life of an open bottle, 2 to 3 days is recommended for the best quality. But even if you store it for over a week in the fridge, it should still be quite tasty.

 PantryFridge
Water (unopened)5 years + 
Water (opened) 3 – 5 days
Sparkling, vitamin or flavored water (unopened)Best-by + 3 months 
Sparkling, vitamin or flavored water (opened) 2 – 3 days

Please note that the periods above are estimates and for the best quality only.

Running water from a tap
(credit: Imani)

How To Tell If The Water Is Bad

There usually aren’t any clear signs that water is bad. It doesn’t magically turn yellow or brown, so you need to rely on your senses and common sense.

Start with examining the contents of the bottle. If there are any contaminants or cloudiness, throw it out. Next, give it a good sniff and if it smells off, discard it. The last thing to do is to taste a small amount and decide if it’s good enough or not.

When it comes to good practices, if the bottle is open for much longer than the periods outlined above, discard the water for safety reasons. Chances are it’s perfectly fine, but you can’t be sure of that, so it’s better to err on the side of caution.