How much emergency water and food should I store?
As of 2 November 2026, Ready.gov (FEMA) says to store at least 1 US gallon (3.8 litres) of water per person per day for several days, and that needs can double in very hot weather; the UK government's Be Ready campaign says 3 litres per person per day for drinking and 3 days of water and food. A family of four for 3 days needs 12 gallons (45 litres) under the US rule, or 36 litres of drinking water under the UK rule.
Your household
12 US gallons (45 L) of water
For 4 people for 3 days under Ready.gov's 1 gallon per person per day. UK Be Ready drinking water: 36 litres.
Rule: Ready.gov (FEMA), Water, checked 2026-11-02
Rule: Ready.gov (FEMA), Food, checked 2026-11-02
Rule: GOV.UK Be Ready, Be ready for emergencies, checked 2026-11-02
Rule: NHS, Understanding calories, checked 2026-11-02
The rules side by side
| US · Ready.gov | UK · Be Ready | |
|---|---|---|
| Water | 1 gallon (3.8 L) per person per day, drinking and sanitation | 3 litres per person per day for drinking; more for cooking and washing |
| How long | "Several days" | 3 days |
| Heat | Needs can double in very hot temperatures | — |
| Food | At least a several-day supply of non-perishable food | Non-perishable food for 3 days |
| Pets | Several days' supply of food and water | Pet food and bottled water |
Calories: the NHS general guide is about 2,000 kcal a day for an average woman and 2,500 kcal for an average man.
Worked examplesWater to store, normal climate
| People | 3 days · US rule | 3 days · UK drinking | 7 days · US rule | 7 days · UK drinking | 14 days · US rule | 14 days · UK drinking |
|---|---|---|---|---|---|---|
| 1 | 3 gal (11 L) | 9 L | 7 gal (26 L) | 21 L | 14 gal (53 L) | 42 L |
| 2 | 6 gal (23 L) | 18 L | 14 gal (53 L) | 42 L | 28 gal (106 L) | 84 L |
| 3 | 9 gal (34 L) | 27 L | 21 gal (79 L) | 63 L | 42 gal (159 L) | 126 L |
| 4 | 12 gal (45 L) | 36 L | 28 gal (106 L) | 84 L | 56 gal (212 L) | 168 L |
| 5 | 15 gal (57 L) | 45 L | 35 gal (132 L) | 105 L | 70 gal (265 L) | 210 L |
| 6 | 18 gal (68 L) | 54 L | 42 gal (159 L) | 126 L | 84 gal (318 L) | 252 L |
Very hot weather: double the US figures (Ready.gov). Adult food for 3 days at the NHS guide: 6,000 to 7,500 kcal per adult.
Related on Global Incident Tracker
Emergency kit checklist Is my food safe after a power cut? What to keep in a go-bag Family emergency plan Emergency numbers Power cut near me? (UK)
What this page shows, and what it misses
It multiplies the official per-person figures by your household and days. It does not know about babies (formula needs safe water too), medical conditions, medicines, or how much your pets drink; Ready.gov gives no fixed pet amount. Calorie figures are a general adult guide, not a diet plan, and children's needs vary with age. Store water in sealed containers, check dates and rotate stock.
Ready.gov (public domain); GOV.UK Be Ready and NHS (Open Government Licence v3.0).