Buyer's guide · Water
Three litres per person per day, for three days. Here's how to actually hold that much water in a British house — and what to use when the supply itself is the problem.
UK guidance · Last reviewed September 2026
Independently selected for UK households. We may earn a commission if you buy through our links — it never changes what we recommend.
Autumn & winter 2026 update
Autumn and winter are when UK supply interruptions actually happen — burst mains in a freeze, and flooding that puts a boil-water notice on a whole area. Two seasonal points: never leave a full butt or container where it can freeze solid and split, and store water off the floor if your property has ever taken flood water. Refresh anything you filled more than six months ago.
The straightforward way to hold a household's 72 hours. Stackable, taps cleanly, and stores in a cupboard or garage without dominating the space.
Every option below is one we'd genuinely put in a UK household kit — the difference is budget and how long you need it to last.
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The straightforward way to hold a household's 72 hours. Stackable, taps cleanly, and stores in a cupboard or garage without dominating the space.
Collapses flat until you need it, which is why it actually gets kept. Ideal for refilling from a standpipe or a neighbour's supply during a mains outage.
A reusable, portable back-up alongside your stored water, for the water sources its manufacturer's instructions cover. Not for seawater or chemically contaminated floodwater.
Safety: Use only water sources covered by the manufacturer's instructions. Not for seawater or chemically contaminated floodwater. Follow local water-company advice during an incident and replace filters as directed.
A tougher, longer-lasting filter for households that want one bottle to outlive several emergencies — and for flood scenarios where supply may be out for days.
Not sure how much you actually need? Score your household in three minutes and see exactly which gaps to close first.
Want the whole kit in one place? The Family Ready Pack bundles these picks with the checklist items most households still miss.
View the Family Ready PackMost UK water problems aren't dramatic. A burst main in a freeze, planned works that overrun, or a boil-water notice. A small store at home means you're not left worrying while it's sorted out.
1. Store around 3 litres per person per day, for three days. That's about 36 litres for a family of four, plus extra for pets.
2. Split it into two or three containers in different places, rather than one heavy drum.
3. Rotate every six months, for example when the clocks change.
4. Follow your water company if you get a boil-water notice or other advice, follow your water company's specific instructions for your area.
If someone in your home may need extra help, it's worth asking your water company about its Priority Services Register. The support available, including any bottled-water arrangements, depends on your circumstances and your provider.
Stored water is instant and needs no thought when you're stressed. Filters are your insurance for contamination and for outages that outlast your stored litres. Get 36 litres in the house before you spend anything on filtration.
Don't put all your water in one container. Two 20-litre cubes in different places survive a leak, a flood or a blocked room; one 40-litre drum does not — and it's too heavy to move once full.
In a flood the mains may still run but be unsafe. That's a filtration problem, not a storage one, and it's the reason a filter bottle per person belongs in the grab bag by the door.
Twice a year, tied to something you already do — the clocks changing works well. Water that has sat for three years is the most common failure in an otherwise good kit.
Reading guides is the easy half. Check your household score first — three minutes, no signup, and it shows you which of these gaps actually apply to you.
Plan for 3 litres per person per day for drinking and basic hygiene — about 9 litres per person over a 72-hour window. A family of four therefore needs roughly 36 litres, plus a little extra for pets.
Tap water kept in clean, sealed, food-grade containers away from sunlight is fine for around six months. Rotate it twice a year — pour it on the garden and refill on the same weekend you change your clocks so you never have to remember a date.
Stored water comes first — it covers you while the mains supply is interrupted. A filter bottle is a portable extra for the water sources its manufacturer's instructions cover. If your water company issues a boil-water notice or other advice, follow its instructions for your area.
Food-grade containers designed for water: collapsible carriers, water cubes or purpose-made jerrycans. Do not reuse milk bottles (protein residue breeds bacteria) or containers that previously held chemicals. Sunlight encourages algae, so store them in a cupboard or garage.
For biological contamination, yes — a rolling boil for one minute is the most reliable household treatment. It does not remove chemical contamination, and it needs a heat source you may not have in a power cut. If your water company issues a notice, follow its specific instructions.
One page, made for the fridge door: what your house needs for three days without power or water. Download it free — no email or newsletter subscription required.
