How much water should you store per person?

By SGWNI. Checked on 2 November 2026.

Store at least 1 gallon of water per person per day. The CDC says to keep enough for 3 days, and 2 weeks if possible. For a family of four, that’s 12 gallons for 3 days and 56 gallons for 2 weeks. Start with the 3 days, then build up as you find space.

What a gallon covers

Ready.gov says a gallon a day is for drinking and sanitation. It also says a typically active adult needs about three-quarters of a gallon of fluid a day, from water and other drinks. That leaves about a quarter of a gallon a day for everything else, which won’t stretch to showers or laundry.

In containers, 12 gallons is about four 24-packs of 16.9 oz bottles, or 12 one-gallon jugs. Fifty-six gallons is twelve 5-gallon containers, with a little to spare. A full 5-gallon container weighs about 42 pounds, so keep them where you won’t have to carry them far.

Our water storage calculator does this for your household and counts what you already have.

When you need more than a gallon

The CDC says to store more for people who are pregnant or sick, for pets, and if you live in a hot climate. Ready.gov adds children and nursing mothers, and says water needs can double in very hot temperatures. Neither gives an amount for most of these, so round up when you can.

No federal source gives a volume for pets. Any figure, including the one in our calculator, is an estimate.

Store-bought or fill your own?

The CDC calls unopened commercially bottled water the safest and most reliable option in an emergency.

• Bottled water: keep it sealed, in a cool, dark place, and check the expiration date.
• Water you bottle yourself: replace it every 6 months. Label each container “drinking water” with the date.

Choosing and cleaning containers

Use food-grade containers, which the CDC says you can find at surplus or camping stores. If you can’t get them, choose something with a tight lid, made of durable material that won’t break, so not glass, ideally with a narrow opening. Never use a container that held a toxic chemical such as bleach or pesticide.

To clean a container before filling it, the CDC says:

1. Wash it with soap and rinse it well.
2. Make a solution of 1 teaspoon of unscented liquid household bleach (5% to 9% sodium hypochlorite) in 1 quart of water.
3. Put it in the container, cover it tightly and shake so it reaches every surface. Wait at least 30 seconds, then pour it out.
4. Let the container air-dry completely.
5. Fill it with clean water and seal it tightly.

That teaspoon is for cleaning containers only. It isn’t a dose for treating drinking water.

Where to keep it

The CDC suggests a cool place, 50°F to 70°F, out of direct sunlight and away from toxic things such as gasoline and pesticides. When you use stored water, take a clean scoop each time, and don’t put your hands in the water or touch the inside of the container.

How to use it in an emergency

Ready.gov’s advice surprises some people: don’t ration drinking water unless authorities tell you to. Drink what you need today, and reduce your need by staying cool and cutting back on activity. Drink water you know is safe first. Ready.gov also says caffeinated drinks, soda and alcohol don’t replace water.

If you run out

• Boil it. The CDC calls boiling the best way to kill germs. Filter cloudy water or let it settle, then use a rolling boil for 1 minute, or 3 minutes above 5,000 feet. EPA uses 5,000 feet and the CDC 6,500 feet, so we give the lower one.
• Use bleach if you can’t boil. Plain unscented bleach, measured in drops. Our water purification calculator gives the dose for your volume and bleach strength.
• Portable filters aren’t enough on their own. The CDC says they won’t remove viruses, and recommends a chemical disinfectant after filtering.
• Chemicals are different. The CDC says boiling and disinfecting can’t make water safe if it’s contaminated with fuel or toxic chemicals. Use bottled water or another source.

A sensible order

1. Buy or fill 3 gallons per person. Do this first, even if your food supply isn’t finished.
2. Add a little extra if you have a baby, someone sick, or live somewhere hot.
3. Put a reminder on your calendar for 6 months out, if you filled your own containers.
4. Build toward 2 weeks a case at a time, if you have the room.