Will there be power cuts in the UK due to the Iran war? What the grid operator's notices show

Will there be power cuts in the UK due to the Iran war?

The question is being typed into search engines as the conflict in the Middle East keeps energy prices high. The short answer from the official record: no one responsible for Britain's power or gas has said the war will cause power cuts here, and their winter assessments say supply is expected to hold.

That is narrower than a promise. Every official assessment names risks, and none of them can rule out a cut. What they do not do is link the war to power cuts in Britain. This page sets out what each body has said, what our own trackers show, and what it means at home. Our standing guide, will there be power cuts this winter, has the full winter picture.

What the grid operator says about this winter

The National Energy System Operator (NESO) balances Great Britain's electricity grid. Its Winter Outlook, published on 23 October 2026, puts the spare margin above peak demand at 5.9 gigawatts (GW), a 9.5% buffer, within the government's reliability standard. Its press release that day said the report "comes against a backdrop of continued disruption in global energy markets, with the ongoing conflicts in the Middle East and Ukraine pushing energy prices higher."

Its conclusion was that Britain's electricity margins are sufficient for the winter, and that the surplus is expected to be higher than during the 2022 energy crisis, when the system operated securely with smaller margins. NESO says there may still be some tight days, most likely in December or January outside the Christmas period, when it may use standard tools such as system notices.

NESO's outlook covers Great Britain. Northern Ireland's grid is run separately and is not in these figures.

What our grid-notice tracker shows

Our grid warnings tracker reads NESO's system warnings as they are published on Elexon's BMRS. At 1:44pm on 11 November no Electricity Margin Notice or other grid warning was in force, and our tracker listed no gas deficit warning from National Gas.

In the 12 months to 11 November, NESO issued seven Electricity Margin Notices, all between June and November 2026, and cancelled all seven. The latest was issued on the evening of Sunday 8 November for 6am to 11am on Monday 9 November, with a shortfall of 1,388 megawatts (MW) against the cushion NESO wanted; by its last update the window was 8am to 11am and the shortfall 200 MW, and NESO cancelled it at 9:11am. For comparison, NESO's own reviews record no margin notices in winter 2025/26 and one in winter 2024/25. Only the 9 November notice falls in this winter.

A margin notice is a message to the electricity market asking for more spare capacity. The 9 November notice carries NESO's note that it "does not signal that blackouts are imminent or that there is not enough generation to meet current demand." The notice for 9 November gives no cause. NESO's account of the 24 June notice put it down to unusually high temperatures, with wind and gas generation availability lower than expected.

NESO also requested Emergency Assistance from neighbouring grids on two days in the week before 14 October. In an explainer that day it put this down to network constraints, and on one of the days a sudden fall in wind, and said "Great Britain had not run out of electricity". It says Emergency Assistance "does not mean supplies have been lost or customers face immediate disruption."

Gas: where the war does reach Britain

The conflict matters to Britain mainly through gas, which DESNZ says is "currently essential for heating homes and businesses, generating electricity, and powering industry and services". The government's national risk assessment on security of gas supply, published by DESNZ on 23 October 2026, says the conflict restricted shipping routes in the Strait of Hormuz and damaged gas facilities in the region. It adds: "Given the UK only sources c1% of gas from the Middle East it did not experience a physical interruption of gas supplies as a result of the conflict." Its overall finding is that the UK gas market "remains resilient".

National Gas's Gas Winter Outlook 2026 says Britain has enough supply capability to meet peak demand this winter, while warning that disruption in other markets, such as the conflict in the Middle East, could affect Britain through the global market for liquefied gas. Our gas storage tracker showed 10.4 terawatt hours (TWh) in Great Britain's storage sites on 10 November, against 17.0 TWh on the same date last year. Storage is one source among several: DESNZ says UK production and imports from Norway each supplied around 40% of the UK's gas in 2025.

Prices, not power cuts, are what has changed at home

The clearest household effect so far is on bills. Ofgem's 26 August 2026 announcement of a 4% price cap rise from October said: "This increase reflects higher wholesale gas prices as a result of the ongoing conflict in the Middle East". Most of the rise was on gas; Ofgem said electricity bills remain broadly stable because VAT was removed from electricity.

Ofgem says it will announce the cap for 1 January to 31 March 2027 by 25 November 2026. Our winter gas and electricity explainer puts the bills picture alongside supply.

What it means at home

Nothing official asks households to do anything new because of the war. Most power cuts are local, Be Ready says, caused by severe weather damaging infrastructure or by system faults. The government's Be Ready page says: "The UK has a resilient electricity system. Most power cuts are short-lived and occur locally, but more widespread and longer outages can happen."

Its basics: a battery or wind-up torch and radio with spare batteries, at least three days of bottled water (3 litres per person per day) and food that needs no cooking and a tin opener, a small amount of cash, and the number 105 written down to report a power cut in England, Scotland and Wales (03457 643643 in Northern Ireland). If you're eligible, sign up to your energy supplier's Priority Service Register. If you use medical equipment that needs power, Be Ready says to make a plan now with your care provider or clinical team.

Be Ready also suggests finding your load block letter at powercut105.com. In the unlikely event of a national energy shortage, it says, emergency cuts could be scheduled area by area, for around three hours at a time. That is a contingency plan, not something any body has said is coming.