Understand shelf life for bottled and home-filled water, why dates and storage conditions matter, and a simple rotation schedule you can follow.
- Follow the printed date on bottled water.
- Rotate home-filled containers on a fixed schedule, no longer than about a year.
- Store water cool, dark and sealed, and check it before drinking.
Water itself does not spoil the way milk does, yet "how long will it keep?" is a fair question. The answer depends on what it is stored in, how clean it was when sealed, and where it sits. This guide separates commercial bottled water from water you fill yourself, and gives you a rotation habit that is easy to keep.
Commercially bottled water
Sealed bottled water is the easiest option because it is filled and capped under controlled conditions. Many bottles carry a best-before or expiry date. That date is mainly about the container and taste rather than the water suddenly becoming dangerous, but it is the date the manufacturer stands behind.
- Check the label and use the printed date as your guide.
- Keep bottles sealed until needed. Once opened, drink the contents promptly or treat them as ordinary tap water.
- Plastic can take on odours from nearby chemicals, so keep bottles away from fuel, paint and cleaning products.
Water you fill yourself
Home-filled containers depend on how clean the container and the water were. Official sources give slightly different intervals. Some US guidance suggests replacing stored water about every six months, while many preparedness plans use a rotation of roughly once a year. A practical approach is to choose a fixed schedule that you will actually follow, and do not stretch it past a year.
If your container is properly cleaned (see best water storage containers), filled from a safe, treated supply and sealed tightly, it can stay in good condition for a long time. If you have any doubt, treat it before drinking, using the steps in our guide to purifying water.
What shortens the life of stored water
- Heat. Warm storage encourages bacterial growth and speeds up plastic breakdown.
- Light. Sunlight promotes algae in clear or translucent containers.
- Contaminated containers. Poorly cleaned jugs, especially reused milk jugs, start with germs already inside.
- Poor seals. Loose caps allow air, dust and insects to get in.
- Strong odours nearby. Plastic is slightly permeable to vapours from petrol, solvents and pesticides.
Signs to check before drinking
Look at the water. If it is cloudy, has floating particles, smells odd or tastes strange, do not just drink it. Water that has been stored for a long time may taste flat because it has lost dissolved air. You can improve the taste by pouring it back and forth between two clean containers.
If the water looks and smells normal but you are unsure about its age or how it was stored, disinfect it first, either by boiling or with an approved chemical method. Our page on bleach and tablets shows how. If water is cloudy or smells of chemicals, discard it or use it for flushing and cleaning, not drinking.
A simple rotation plan
- Write the fill date on every container with a permanent marker or a label.
- Choose a rotation point, for example when the clocks change in spring and autumn, or on a fixed date each year.
- At that point, empty older containers by using the water for cooking, pets, plants or cleaning, rather than pouring away all of it. Then wash, sanitize and refill.
- Put the oldest containers at the front so they are used first.
- Check lids and seals for cracks and leaks while you are at it.
How much to keep
Rotation is much less of a chore if you keep a realistic amount. The usual planning number is 4 litres (1 gallon) per person per day for drinking and basic hygiene, and many people aim for at least three days, with more for a longer plan. See how much water to store to work out your own household numbers, and browse supplies in the water hub.
Quick answers
Does bottled water expire?
Many bottles carry a best-before date. It mostly reflects container and taste quality, but use the date as your guide.
Can I drink water that has been stored for years?
Look, smell and taste it first, and disinfect it if you are unsure. If it is cloudy or smells of chemicals, do not drink it.