Only situations with a published figure are listed. A blank isn't “forever” — it means no reliable number is published for it.
Storage
Store at: Cool, dry pantry away from heat and light
Refrigerate after opening: Optional — mainly for quality, not safety
USDA FoodKeeper v128 tip (pantry storage): Water will store indefinitely, though the taste may be impacted by storage conditions, including sunlight, items stored around it and the containers being used to store it.
How to tell if Water (commercially bottled) has gone bad
Sour or off smell
Cloudiness, sediment, or curdling
Fizzing in a still drink, or a swollen carton or can
A bitter or 'off' first sip
USDA FoodKeeper v128 publishes no spoilage note for Water (commercially bottled) specifically, so these are the general signs for beverages — never taste something to test it. When in doubt, throw it out.
Air and warmth are what shorten an opened item's life — the right container buys back the days the packaging gives up once the seal's broken.
About Indefinitely, according to USDA FoodKeeper v128, stored as follows: cool, dry pantry away from heat and light.
Does Water (commercially bottled) need to be refrigerated?
Water (commercially bottled) is shelf-stable at room temperature: cool, dry pantry away from heat and light. Refrigerating it mainly preserves quality rather than safety.
How can you tell if Water (commercially bottled) is bad?
Look for: Sour or off smell; Cloudiness, sediment, or curdling; Fizzing in a still drink, or a swollen carton or can; A bitter or 'off' first sip. Those are the general signs for beverages — USDA FoodKeeper v128 publishes no spoilage note for Water (commercially bottled) specifically. Never taste something to test it — when in doubt, throw it out.