Quick answer
Generally, it’s not recommended to drink bottled water that’s been opened and stored for an extended period of time. An unopened, commercially bottled water should be safe to drink for up to 2 years past its printed expiration date, as long as it was properly stored. However, once opened, plastic bottled water is best consumed within 6 months. Glass bottled water can last up to a year after opening if properly sealed and stored. Regardless of packaging, if the water smells or tastes off, it’s best not to drink it.
How long can you store bottled water?
The shelf life of bottled water depends on a few key factors:
- Container type – Plastic vs. glass
- Seal – Is the bottle still properly sealed or has it been opened?
- Storage conditions – Temperature, sunlight exposure, cleanliness of storage area
- Source – Was it commercially purified or from a natural spring/mineral source?
Here are some general guidelines on how long bottled water lasts:
Unopened bottled water:
- Commercially purified water in plastic bottles – 2 years from printed expiration date
- Natural spring/mineral water in plastic bottles – 1 year from printed expiration date
- Water in glass bottles – Indefinite; taste may eventually degrade over many years
The key is that the bottle remains properly sealed. Over time, plastic bottles may start to lose their structural integrity, increasing risk of leakage and contamination.
Opened bottled water:
Once opened, the shelf life drops considerably due to the introduction of oxygen and increased risk of contamination:
- Plastic bottles – 3-6 months
- Glass bottles – 6-12 months if properly resealed
Does plastic vs. glass packaging affect safety?
There are a few key differences between plastic and glass bottles in terms of water safety and shelf life:
Plastic:
- Porous material allows more oxygen exposure – limits shelf life after opening
- Higher risk of chemical leaching from plastic into water over time
- Lower UV light protection – sunlight accelerates plastic degradation
- Generally recommended for shorter term storage (under 1 year)
Glass:
- Non-porous so less oxygen exposure if properly sealed
- No risk of chemical leaching
- Blocks UV light, extending shelf life
- Recommended for longer term storage (1-2 years or more)
So glass bottled water may have a slight safety advantage in terms of shelf life and avoiding plastic chemical leaching. However, plastic is more convenient, portable, and less prone to breakage. For short term storage under 6 months, plastic bottles are considered safe for water if properly sealed.
How do storage conditions affect shelf life of bottled water?
Proper storage is key to maximizing the shelf life of bottled water. Here are some tips:
Temperature:
- Store at moderate room temperature – avoid temperature extremes
- Avoid direct sunlight, which can heat water in plastic bottles
- Do not freeze water in plastic bottles due to risk of bottle deterioration
Light exposure:
- Keep away from direct sunlight – causes plastic degradation
- Store in a dark pantry or cupboard if possible
Cleanliness:
- Wipe down bottles before storage to remove dirt, dust, and other contaminants
- Store in a clean, dry area away from chemical products
Following these best practices helps prevent degradation of water quality and plastic over time. Refrigeration can also extend shelf life after opening by slowing bacterial growth.
What are signs that opened bottled water has gone bad?
Here are some red flags that opened bottled water may no longer be safe to drink:
- Cloudiness or particulate matter – Indicates microbial growth
- Strange odors – Smells like chemicals, rotting eggs, or other pungent scents
- Off tastes – Metallic, soapy, bitter, or other odd flavors
- Discoloration – No longer clear; may turn yellow or brown
- Bottle bloating or leakage – Signals bacterial contamination
- Expired dates – Past expiration dates on commercially sealed bottles
If in doubt, it’s best to err on the side of caution and avoid drinking questionable water. Odors, taste, and appearance are important clues signaling microbial spoilage. When water passes the expiration date or looks, smells, or tastes off, replace it with a fresh sealed bottle.
What causes bottled water to go bad after opening?
There are a few main factors that limit the shelf life of bottled water after it’s been opened:
Oxygen exposure – Introduces oxygen that can react with compounds in the water, affecting taste/odor and allowing microbial growth.
Microbial contamination – Bacteria, mold spores, yeasts, etc. can enter via air, hands, dirty storage areas. They multiply over time if conditions allow.
Chemical leaching – In plastic bottles, chemicals in plastic like BPA may gradually leach into the water, especially if stored in warm or sunny areas.
UV light degradation – In plastic bottles, sunlight exposure degrades the plastic and can cause an off-taste or smell to the water.
Proper post-opening storage in a cool, dark environment, like the refrigerator, helps slow these processes and extend shelf life. But eventually, chemical and microbial changes will lower water quality and safety.
How long does unopened commercially bottled water last?
Here are the typical shelf lives for unopened, commercially bottled water if properly stored:
| Type of Bottled Water | Shelf Life |
|---|---|
| Purified water in plastic bottles | 2 years from printed expiration date |
| Spring or mineral water in plastic | 1 year from printed expiration date |
| Water in glass bottles | Indefinite; taste may eventually degrade |
The expiration date assumes proper storage at moderate room temperature and out of direct light. Exceeding the 2 year limit for purified water or 1 year for spring/mineral water doesn’t necessarily mean the unopened water is unsafe to drink, but it may start to show degraded quality. If not stored properly, the shelf life can be shorter.
Does refrigeration extend the shelf life of bottled water?
Yes, refrigeration can help extend the shelf life of bottled water, especially after opening. The CDC recommends refrigerating opened bottled water and using it within 6 months for best quality.
Refrigeration slows microbial growth by lowering the temperature. The cool environment helps limit chemical reactions that can degrade taste and odor. For plastic bottles, refrigeration also limits plastic deterioration caused by heat and sunlight exposure.
Properly stored in the refrigerator, opened bottled water can last:
- Plastic bottles – 3-6 months
- Glass bottles – 6-12 months
The shelf life depends on the purity and quality of the original water. Higher mineral content provides nutrition for more microbial growth, so spring or mineral water has a shorter refrigerated shelf life than purified water.
Refrigeration can also extend the shelf life of unopened commercially bottled water past the expiration date on the label by 1-2 years if the seal remains intact.
What are the best ways to store bottled water for safety?
To maximize freshness and shelf life of bottled water, follow these storage tips:
For unopened bottles:
- Store at moderate room temperature – avoid temperature extremes
- Keep away from direct sunlight and other heat sources
- Avoid storing near chemical products, gasoline, solvents, or cleaners
- Store only sealed, undamaged bottles
- Wipe down bottles to remove dust, dirt, or other contaminants
For opened bottles:
- Refrigerate after opening
- Screw cap on tightly or use bottle stoppers to seal
- Use opened water within 6 months for best quality
- Keep refrigerated storage area clean
- Keep away from foods with strong odors that could get absorbed
Following safe bottled water storage practices ensures you get the most shelf life while maintaining water quality and preventing microbial contamination.
Does freezing affect bottled water safety?
Freezing actually preserves the quality and extends the shelf life of sealed, unopened commercially bottled water. The water remains safe to drink after thawing.
However, freezing can affect taste as it concentrates the mineral content. Freezing may also cause plastic water bottles to deteriorate or crack over time due to expansion.
It’s not recommended to freeze opened bottled water. The expansion and contraction of ice crystals can cause plastic bottles to bulge or break. Refrigeration is the best method for storing already opened water.
If freezing opened bottled water, consume within 24 hours after thawing for best quality. The warmth of thawing allows microbial growth.
Here are some freezing tips for bottled water:
- Only freeze unopened commercially sealed water bottles
- Thaw completely before drinking for palatable taste
- Avoid freezing premium spring or mineral water to preserve taste
- Don’t freeze milk or juice – separates and becomes unpalatable
- Consume thawed opened water within 24 hours
Freezing can extend shelf life of unopened bottled water almost indefinitely. But it can make opened water unsafe if stored frozen more than a day after thawing.
Does bottled water expire?
Yes, bottled water does technically expire and has a limited shelf life. However, expiration dates on water bottles are generally conservative estimates for best quality.
Here’s how long commercially bottled water lasts:
Unopened:
- Purified water – 2 years from printed expiration date
- Spring/mineral water – 1 year from printed expiration
- Glass bottled – Indefinite; taste degrades over years
Opened:
- Plastic bottles – 3-6 months
- Glass bottles – 6-12 months if properly sealed
After the printed expiration date, unopened plastic bottled water is likely still safe to consume but may have some taste degradation.
The shelf lives assume proper storage conditions. Heat and sunlight significantly reduce shelf life of bottled water. While not a food safety risk, expired water may start to develop an off-taste or odors.
Can you drink bottled water years after the expiration date?
It’s generally not recommended to drink bottled water years past the printed expiration date on the label. Over years, degradation in water quality is likely. However, if the bottle remains properly sealed and stored, the water is likely still safe to consume but may not taste fresh.
Here are some considerations when drinking years-old bottled water:
- Smell and look for off odors, colors, cloudiness, sediments
- Take a small sip to check for off tastes or textures
- Avoid water stored near gasoline, chemicals, or in contaminated areas
- Don’t drink if plastic bottle shows signs of damage or leaks
The longer water sits, the more opportunity for plastic degradation, leaching of chemicals into the water, and permeation of outside odors. Taste bottled water first and if any signs of spoilage, err on the side of caution and avoid drinking it.
While not necessarily unsafe, the quality of bottled water years beyond its expiration date may be subpar. For best taste and freshness, it’s advisable to replace extremely expired bottled water.
Does bottled water go bad if left in a hot car?
Yes, the heat in a hot car can significantly reduce the shelf life and safety of bottled water. According to food safety experts, bottled water or any beverages are best kept out of vehicles in hot weather.
Heat speeds up chemical reactions and plastic degradation. In very hot cars, plastic water bottles left inside for extended periods can actually melt or warp.
The hot interior can also increase chemical leaching from the plastic into the water. This can lead to off-tastes.
Additionally, warm temperatures allow rapid microbial growth if bottles have been opened. Bacteria thrive at warm conditions.
Any type of bottled beverage, including water, juice drinks, or soda, should be kept out of hot vehicles. Store in a cool, shaded area instead to maximize freshness.
If bottled water seems extremely warm after being left in a hot car, it’s safest to discard it. Drinking overheated water with degraded plastic poses health risks.
Conclusion
Drinking water that’s been stored for a long time or under poor conditions has some risks, but using proper storage and watching for any changes in taste, smell or appearance can help mitigate those risks. Water in commercially sealed bottles should stay fresh for up to 2 years, but once opened the clock starts ticking fast – plastic bottles should be used within 6 months and glass bottles within a year. Keeping water out of hot cars and direct sunlight, refrigerating when possible, wiping bottles down before storage and checking for damage or contamination are all things that can extend the shelf life of bottled water. While it’s ideal to stay within the standard expiration times, even water that’s years past its date or been frozen and thawed can still be safe to drink if it appears normal. However, quality and taste are likely to degrade the longer water sits. As long as you carefully inspect bottled water for any issues before drinking, pay attention to how the water looks and smells, and try to stay within the recommended shelf life, drinking bottled water stored for varying lengths of time should pose minimal risks.
