If the UK were drawn into a war: what would change at home

Last checked 28 October 2026. Based on the Strategic Defence Review 2025, the National Risk Register, GOV.UK Be Ready and Sweden's official advice.

What the government has said

The Strategic Defence Review, published in June 2025, says that "for the first time since the end of the Cold War, the UK faces multiple, direct threats to its security". It calls for national preparedness and resilience so the country "can withstand attacks and recover quickly", and says everyone has a role to play. It lists sabotage and cyber attacks on critical services among the threats. It does not give instructions to households.

The government's Be Ready campaign, launched in October 2026, asks every household to be able to cope for three days if power, water, phones or the internet are disrupted. It covers storms, cyber attacks and other emergencies. It is general advice, not a warning about a specific threat.

What would most likely affect your home

• Power. The government's own planning scenario for a failure of the national grid says full restoration could take up to 7 days. In a national energy shortage, power can be cut by area in turns of around three hours. Your area's letter is on some electricity bills and at powercut105.com.
• Phones and internet. Mobile masts and broadband need power. Your phone may stop working if the local mast loses power.
• Payments. Card machines and cash machines need power and networks, which is why the government says to keep some cash.
• Water. Mains water can be disrupted during and after a long power cut, because pumping stations need electricity.
• Information. Official warnings come through UK Emergency Alerts on your phone, local radio and TV, and GOV.UK. False stories spread fast in a crisis, so check the source before you share anything.

What to do now

• Keep three days of water and food at home. See how long your home would last.
• Keep a battery or wind-up radio, with local station frequencies written down.
• Keep some cash in notes and coins. How much cash to keep.
• Write key phone numbers on paper, including 105 for power cuts.
• Keep phone software up to date and leave Emergency Alerts switched on.
• Agree with your household where you would meet if you were split up. Leaving home in a hurry.
• Check on older or vulnerable neighbours.

How other countries do it

In November 2024 Sweden posted its booklet "If crisis or war comes" to every home. Its advice is to plan to manage on your own for at least a week, with 3 to 5 litres of water per person per day, a battery or wind-up radio, some cash and a month of regular prescription medicines. The UK's advice is shorter but covers the same ground.