How much water to store per person per day?

Short answer. Store at least one gallon (about 3.8 litres) of water per person per day, the US figure from Ready.gov and the CDC ¹², for 3 days and, if possible, 2 weeks ². Canada says about 4 litres ³, Sweden 3 to 5 litres ⁶, Germany 2 litres for drinking and cooking only ⁴. Add more for heat, illness, pregnancy and pets ¹².

Why do the official numbers differ from country to country?

The figures look inconsistent until you check what each one is meant to cover. Some agencies count only what you drink and cook with; others include washing and basic sanitation.

• Drinking and cooking only. Germany's BBK says an adult needs at least 1.5 litres of fluid a day, plus 0.5 litres if you want to cook, for a total of 2 litres ⁴. Switzerland recommends at least 9 litres per person, enough for drinking and cooking for three days, which works out to 3 litres a day; water for personal hygiene and toilet flushing is explicitly not included ⁵.
• Drinking, cooking and basic hygiene. Sweden's MCF counts three to five litres per adult per day and says this should cover drinking, cooking and basic hygiene ⁶. Canada asks for about 4 litres per person per day and names drinking, cooking and sanitation as what emergency water is for ³.
• Drinking and sanitation. Ready.gov's one gallon per person per day is "for drinking and sanitation" ¹.

So the German 2 litres and the American gallon are not in contradiction: they answer different questions. If you follow a drinking-only figure, plan separate water for washing and the toilet ⁵.

How much water is that for my household?

The table converts the main official recommendations into totals. Daily amounts are as published; totals are simple multiplication.

A family of four following the CDC's two-week target needs 56 gallons, roughly 212 litres. That takes real storage space, so starting with the 3-day minimum and building up toward the longer target is a practical approach.

What official agencies recommend

United States (Ready.gov and CDC). Store at least one gallon per person per day for several days ¹. The CDC sets the floor at a 3-day supply and recommends 2 weeks where possible ². Ready.gov adds: "Never ration drinking water unless ordered to do so by authorities" ¹.

Canada. Plan on about four litres per person per day; the government lists drinking, cooking and sanitation as the uses of emergency water. Be ready to be self-sufficient for at least 72 hours ³. Include small bottles that are easy to carry if you must leave ³.

Germany (BBK). At least 1.5 litres of fluid per adult per day, plus 0.5 litres for cooking ⁴. The BBK asks households to be able to supply themselves for ten days if possible, and at least three days ⁴. Part of the drinks supply should be (mineral) water; other drinks such as juice can count toward it ⁴.

Switzerland (BWL/FONES). At least 9 litres per person, which the office describes as one six-pack of 1.5-litre bottles, enough for drinking and cooking for three days ⁵. Hygiene and toilet water come on top ⁵.

Sweden (MCF and Krisinformation.se). Three to five litres per adult per day, covering drinking, cooking and basic hygiene ⁶. Sweden asks households to manage on their own for at least a week without electricity or water ⁷.

Do children, pregnant women, sick people and hot weather change the amount?

Yes. Ready.gov states that children, nursing mothers and sick people may need more water ¹. The CDC says to consider storing more for pregnant people, people who are sick, and anyone living in a hot climate ². In very hot temperatures, water needs can double, according to Ready.gov ¹.

None of the agencies reviewed here publishes a separate per-child figure. The practical reading is to count every household member, including infants, as a full person, then add margin for heat and illness. If anyone in the household depends on water for medical reasons, such as mixing infant formula or a medical device, ask the prescribing clinician how much to set aside.

How much water do pets need?

The CDC lists pets among the reasons to store more water than the base amount ². Ready.gov asks pet owners to store a water bowl and several days' supply of water for the animal ⁸. Sweden's guidance also reminds households that pets need water ⁶⁷. None of these agencies gives a per-animal quantity, so check with your veterinarian for your animal's size and species, and keep that water separate from the household count.

How should I store and rotate emergency water?

Commercial bottled water is the simplest option. The CDC calls unopened, commercially bottled water the safest and most reliable choice ². Ready.gov says to keep it sealed in the original container in a cool, dark place ¹. Check the expiration date ².

If you fill your own containers:

• Use food-grade water storage containers ¹. The CDC specifies FDA-approved food-grade containers, with tight-closing lids, made of durable, unbreakable material (not glass) ².
• Never reuse containers that held toxic chemicals such as bleach or pesticides ².
• Label each container "drinking water" with the date you filled it ².
• Store it somewhere cool, between 50°F and 70°F (10–21°C), out of direct sunlight and away from gasoline, pesticides and similar substances ². Sweden's MCF likewise advises keeping water dark and as cool as possible, using clean, well-sealed jerrycans intended for drinking water and filled with good-quality drinking water such as municipal tap water ⁶.

Rotation.

• Replace water you bottled yourself every six months ¹².
• Sweden suggests checking your stored water once or twice a year and changing it if needed ⁶.
• Canada recommends replacing items that can expire, including water, at least once a year ³.
• Germany's BBK recommends a fixed yearly check of expiry dates and using the oldest items first, then restocking ("lebender Vorrat") ⁴.

Freezing. Sweden's MCF suggests freezing PET bottles as a smart way to prepare, and warns not to fill them to the top, because they burst when the water freezes ⁶.

Frequently asked questions

Is one gallon per person per day enough?

It is the US baseline for drinking and sanitation ¹². In very hot weather needs can double ¹, and children, nursing mothers, pregnant people and sick people may need more ¹². Treat a gallon as a floor, not a target.

How many days of water should I store?

It depends on the country: at least 72 hours in Canada ³, 3 days in Switzerland ⁵, at least a week in Sweden ⁷, ideally 10 days in Germany ⁴, and 3 days minimum with 2 weeks recommended by the CDC ². Start with 3 days, then extend toward your own agency's longer target.

How long does stored water last?

Water you bottle yourself should be replaced every six months ¹². For commercially bottled water, keep it sealed in the original container ¹ and observe the expiration date ².

Should I ration water during an emergency?

No. Ready.gov's guidance is to never ration drinking water unless authorities order you to ¹. Drink what you need today and look for more tomorrow.

Does the Swiss 9 litres include washing?

No. The 9 litres per person cover drinking and cooking for three days; water for personal hygiene and toilet flushing is not included ⁵.

Next step: build your kit

Water appears on the official kit lists of every agency cited here ¹³⁴⁵⁷, but quantities and durations depend on where you live. Check your own national agency's figures and use them to set your water target, container sizes and rotation schedule.

Sources

1. Ready.gov (U.S. Department of Homeland Security / FEMA) — Water — https://www.ready.gov/water (accessed 2026-10-20)
2. Centers for Disease Control and Prevention — How to Create an Emergency Water Supply — https://www.cdc.gov/water-emergency/about/how-to-create-and-store-an-emergency-water-supply.html (accessed 2026-10-20)
3. Government of Canada — Emergency kits — https://www.canada.ca/en/services/policing/emergencies/preparedness/get-prepared/emergency-kits.html (accessed 2026-10-20)
4. Bundesamt für Bevölkerungsschutz und Katastrophenhilfe (BBK) — Essen und Trinken bevorraten — https://www.bbk.bund.de/DE/Warnung-Vorsorge/Vorsorge/So-koennen-Sie-sich-vorbereiten/Bevorraten/bevorraten_node.html (accessed 2026-10-20)
5. Federal Office for National Economic Supply (BWL/FONES), Switzerland — Kluger Rat – Notvorrat — https://www.bwl.admin.ch/de/kluger-rat-notvorrat (accessed 2026-10-20)
6. Myndigheten för civilt försvar (MCF), Sweden — Tillgång till vatten i kris — https://www.mcf.se/sv/rad-till-privatpersoner/hemberedskap---preppa-for-en-vecka/vatten/tillgang-till-vatten-i-kris/ (accessed 2026-10-20)
7. Krisinformation.se — Home Preparedness — https://www.krisinformation.se/en/get-prepared/home-preparedness/ (accessed 2026-10-20)
8. Ready.gov (U.S. Department of Homeland Security / FEMA) — Pets and Animals — https://www.ready.gov/pets (accessed 2026-10-20)