The short answer
No official source gives a chance of nuclear war involving the UK, and we won't guess one. The government's National Risk Register 2026 keeps its scenario for a nuclear attack on the UK classified. The one nuclear risk it scores in public is a limited nuclear conflict between two other states, not involving the UK or its allies, which it rates a 1–5% chance over its assessment period. The government says nuclear risks are rising as other states build up their arsenals, while NATO says the circumstances in which it might use nuclear weapons are extremely remote. Whatever happens in the news, the useful steps at home are the same: 3 days of supplies, a radio, and knowing go in, stay in, tune in.
What changed this month (checked 1 November 2026). No change to the UK's public nuclear risk position since the National Risk Register 2026 (published July 2026). On 14 October 2026 the UK told the OSCE that NATO "is not at war with Russia" and that deterrence "is a promise that aggression will fail". We review this box each month.
The honest answer: no one can give you a number
You'll find percentages online. None of them come from the UK government. Here's what the official sources actually publish.
1. The UK attack scenario is classified. The National Risk Register (NRR) 2026 is the public summary of what the government plans for. A footnote says a scenario for a nuclear attack on the UK mainland or UK overseas interests exists and is held internally at a higher classification. It isn't scored in public.
2. One nuclear risk is scored in public, and it doesn't involve the UK. The NRR's risk called "Nuclear miscalculation not involving the UK or its allies" imagines a limited nuclear conflict between two other states. On the NRR's risk matrix it sits at: - impact 4 out of 5 ("significant") for the UK - likelihood 3 out of 5, which the NRR defines as a 1–5% chance of that worst case happening at least once during the assessment period (2 years for malicious risks, 5 years for others). On the intelligence yardstick the NRR uses, that's a "remote chance".
The NRR's chart for this risk shows wide uncertainty lines, so treat the score as a planning estimate, not a precise figure.
The effects the NRR expects for the UK are knock-on effects: economic disruption, support for British nationals in the region, possible migration pressures, and disruption to supply chains and flights. It says the UK keeps civilian staff qualified to monitor radiation levels.
The NRR also says all the risks in it are "relatively low likelihood events". It's a planning tool, not a forecast.
What the government says about the trend
When announcing the purchase of nuclear-capable F-35A jets in June 2025, the Defence Secretary said the Strategic Defence Review confirmed "we face new nuclear risks", with other states increasing, modernising and diversifying their nuclear arsenals. The government's response has been to strengthen deterrence. For the numbers, see how many nuclear warheads the UK has.
What NATO says
NATO says the purpose of its nuclear weapons is to "preserve peace, prevent coercion and deter aggression", and that the circumstances in which it might have to use them are "extremely remote" (NATO's nuclear deterrence page, updated 25 September 2026).
What about the Atomic Scientists' clock?
The Bulletin of the Atomic Scientists set its symbolic clock at 85 seconds to midnight on 27 January 2026, the closest it has ever been. Two things to know:
- It's an outside expert view, not a government assessment.
- The Bulletin describes the clock as a metaphor and a reminder of dangers. It doesn't give a probability.
Why headlines spike
Searches for "how likely is nuclear war in 2026" jumped this autumn. Spikes like this usually follow news, not new official assessments. The latest official assessment is the NRR 2026, published in July 2026. If a headline says something different, check whether it quotes GOV.UK or NATO directly. For the wider question of a world war, our monthly page is WW3 likely? what officials have said collects dated quotes from UK defence chiefs and NATO.
Three calm steps, whatever the news
These are useful in a power cut or flood too, so nothing is wasted.
- Keep 3 days of water and food at home. Be Ready suggests 3 litres of water per person per day.
- Keep a battery or wind-up radio. If power or phones go down, it's how you'll hear instructions.
- Learn go in, stay in, tune in. UKHSA's advice for any radiation emergency: get indoors, stay in (possibly one to two days), and follow official updates. Our nuclear warning guide has the steps.
If the news is getting to you, this post on coping with worry about war has practical ideas, and is there any point preparing for a nuclear attack? answers the question many people ask next.
What to buy
About these links: plain links to ordinary retailer pages. We may earn from some links in future; we don't now. We haven’t tested these and we don’t rank them: they are examples that were in stock when we checked. Prices change. Check what you already own first. Full kit list
Battery or wind-up FM radio
Look for: FM (Be Ready asks for FM; DAB as well is fine). Both a crank and ordinary batteries, so you have two ways to power it.
Bottled water
Look for: 3 litres per person per day for 3 days, for drinking. More for babies, pets and medical devices.
- Seven Oceans Emergency Drinking Water 0.5l (5-year shelf life) · EVAQ8 · £3.94 (price on 1 November 2026) Shop
Torch or head torch, plus spare batteries
Look for: Runs on the same AA or AAA batteries as your other kit, so one spare pack covers everything. A head torch leaves both hands free.
- Alpkit Ionic 350 Lumen Head Torch · Alpkit · £15.99 (price on 1 November 2026) Shop
- Lifesystems Intensity 155 LED Head Torch · Lifesystems (UK brand store) · £19.99 (price on 1 November 2026) Shop
- Alpkit Kula 550 Lumen Head Torch · Alpkit · £19.99 (price on 1 November 2026) Shop
- Lifesystems Intensity 480 LED Hand Torch · Lifesystems (UK brand store) · £29.99 (price on 1 November 2026) Shop
- Dynamo Powered Wind-Up Pocket LED Torch · EVAQ8 · £3.60 (price on 1 November 2026) Shop
Frequently asked questions
Is nuclear war likely in 2026?
No official UK source puts a number on nuclear war involving the UK. The government's own scenario for a nuclear attack on the UK is classified. The one nuclear risk the National Risk Register 2026 scores publicly is a limited nuclear conflict between two other countries, at 1 to 5% likelihood, which it calls a remote chance.
What does the UK government say about nuclear risk?
The Defence Secretary said in June 2025 that the Strategic Defence Review confirmed 'we face new nuclear risks', with other states increasing, modernising and diversifying their nuclear arsenals. The government's answer has been to strengthen deterrence.
What is the Atomic Scientists' clock at in 2026?
The Bulletin of the Atomic Scientists set its clock at 85 seconds to midnight on 27 January 2026, its closest ever. It's an outside expert view, not a government assessment. The Bulletin calls the clock a metaphor and a reminder of dangers; it doesn't give a probability.
Should I worry about nuclear war?
Worry is understandable when the news is full of it. It helps to swap it for a few practical steps that are useful in any emergency: water, food, a radio, a plan. If worry is affecting your sleep or daily life, read our post on coping with worry about war or talk to your GP.
Would a nuclear war end the world?
We didn't find an official UK source that answers this, so we won't guess. The government's published planning covers a limited nuclear conflict elsewhere in the world, with knock-on effects for the UK such as economic disruption and support for British nationals abroad.
Where can I see official updates?
GOV.UK for government statements and Emergency Alerts, the BBC as the UK's emergency broadcaster, and FCDO travel advice if you're abroad. We update this page when official positions change.
Sources
We opened each page on the date shown. Official advice changes: if a source says something different now, follow the source.
- Cabinet Office (GOV.UK): National Risk Register 2026 (published 14 July 2026, updated 12 August 2026) (read 1 November 2026)
- Cabinet Office: National Risk Register 2026 (PDF): likelihood scale (page 15), risk matrix (page 19), conventional attack footnote (page 222), nuclear miscalculation (page 223) (read 1 November 2026)
- Prime Minister's Office and MOD (GOV.UK, 24 June 2025): UK to purchase F-35As and join NATO nuclear mission (quotes from the Defence Secretary on the Strategic Defence Review) (read 1 November 2026)
- FCDO (GOV.UK, 14 October 2026): Deterrence is not a threat, UK statement to the OSCE (read 1 November 2026)
- NATO: Nuclear deterrence (last updated 25 September 2026) (read 1 November 2026)
- Bulletin of the Atomic Scientists: the Clock (set 27 January 2026). Outside expert view, not official (read 1 November 2026)
- UKHSA (GOV.UK): What to do in a radiation emergency (updated 10 September 2024) (read 1 November 2026)
- GOV.UK Be Ready: be ready for emergencies (checklist) (read 1 November 2026)
Related guides
- Radiation emergency in the UK: what official advice says (go in, stay in, tune in)
- Worried about war? How UK households can prepare — calmly
- Why is the government asking us to prepare?
Free tools
We're an independent UK site, not the government. We check guides against official sources and link to them. In an emergency call 999.
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