How Long Does Unrefrigerated Filtered Water Stay Fresh? - Mayu Water Answers

How Long Does Unrefrigerated Filtered Water Stay Fresh?

How long does your water last outside the refrigerator? Find the answer to this and other questions, such as the longevity of bottled water, in this article.

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By Staff Writer
Photograph of Joel Taylor
Edited by Joel Taylor

Published August 1, 2022.

We all have busy lives, and sometimes we forget how long we left our cup of water or water bottle out for; leaving us questioning the fact whether the water we are drinking is safe to drink or not.

How Long Will Filtered Water Last at Room Temperature?

If you leave unrefrigerated filtered water open in a room temperature environment, then it is safe to drink for up to 12 hours. Then carbon dioxide from the air eventually starts to mix in with the water, changing its taste. Also, other microscopic elements, such as dust and debris, can be exposed to your cup of water.

Bottled water is not ideal either, even at room temperature. When we put our mouth to the rim of the bottle, our saliva, sweat, dust, and dead skin gets backwashed into the water, which adds up to a lot of bacteria. Bottled water left in the heat—especially bottles made of BPA or other plastics—can seep harmful chemicals into the water.

If you do not change your water filter after 40 gallons of Brita or every 2 months, bacteria will grow in your filter or get mixed into your water.