Why does bottled water have an expiration date?

Does bottled water have an expiration date? Or why does bottled water have an expiration date because pure water is not always good? This article will give you the answer.

Expiration dates on non-perishable consumer goods are often considered ridiculous. Few people need an explanation for why meat or dairy products have sell-by dates, but other things require more information to understand. For example, child car seats have expiration dates because safety regulations change frequently and because they can wear out after years of daily use.

Yet the date stamped on bottled water seems to defy all rules of common sense. Shouldn't H2O, in theory, be good forever?

The answer is yes — but water quality isn't the issue. A 1987 New Jersey law requires all food products sold there to display an expiration date of two years or less from the date of manufacture. Labeling, separating, and shipping expired water to the Garden State seems a bit inefficient for bottled water manufacturers, so most simply started labeling every bottle with a two-year expiration date, regardless of where it was shipped.

The U.S. Food and Drug Administration has never established or proposed a shelf life limit for bottled water as long as the water is produced according to regulations and the bottle is properly sealed. New Jersey caught on to this fact and changed its law, but the expiration date has been the industry norm for so long that many manufacturers still maintain it.

While unopened 'expired' bottled water won't harm you, it also doesn't get any better with age. The plastic used to hold the water—typically polyethylene terephthalate (PET) for retail bottles and high-density polyethylene (HDPE) for water coolers—can begin to leach into the liquid, affecting the taste of the water. It's also somewhat porous, so the water can absorb odors and other unwanted additives from the outside world. The chances of a five-year-old bottle of Evian harming you are slim to none, but if it's been sitting in your basement, it's probably best to replace it.

Isabella Humphrey

Update 26 May 2025