The Iberian Blackout of April 2025: What Happened and What to Learn

Quick answer: At 12:33 on 28 April 2025, the power grid in mainland Spain and Portugal collapsed. Trains stopped, mobile networks struggled, cash machines and card terminals went down and some taps ran dry. Power came back within about 10 hours in most places, and Spain had restored more than 99% of demand by 7:00 the next morning. The lesson for any household is simple: keep cash, a battery or wind-up radio, lighting, phone power and a few days of water at home.

What happened on 28 April 2025

The blackout hit at 12:33 Central European Summer Time. It affected mainland Spain and Portugal, with brief disruption in south-west France. ENTSO-E, the body that links Europe’s grid operators, calls it the most severe blackout on the European power system in more than 20 years.

It happened very fast. According to the Associated Press, Spain lost 15 gigawatts of power in about five seconds. That was roughly 60% of the country’s demand at the time.

Restoration started within minutes: the first Spanish substation was re-energised at 12:43 using the link from France. Spain’s grid operator, Red Eléctrica, says all of its transmission substations had power again by 4:00 on 29 April, and 99.95% of demand was restored by 7:00. In Portugal, the grid operator REN said all 89 substations were back online by late that night, covering 6.4 million customers.

How daily life was affected

The blackout lasted hours, not days. Even so, it showed how much of normal life depends on electricity.

Trains and roads

Metro and rail services stopped across both countries. Madrid’s metro stations were evacuated. Around 35,000 passengers were rescued from stranded trains and underground systems on the first day, the AP reported. Traffic lights went dark, and in Barcelona ordinary people stepped in to direct traffic.

Phones and information

Some mobile networks went down, and others struggled. Spain’s government asked people to travel as little as possible, to use their phones responsibly and to call the 112 emergency number only when truly needed. It also urged people to follow official channels to avoid rumours.

Cash and card payments

Cash machines shut down and electronic payment systems were disrupted. Petrol stations stopped working too. People with notes and coins at home could still buy food and essentials from shops that stayed open.

Water

In Portugal, the main Lisbon water company, EPAL, explained that its supply depends heavily on electricity. Power runs the treatment plants and the pumps that push water to homes and up into buildings. Places including Sintra, Mirandela and Lisbon’s Alvalade district had interruptions. When power returned, some taps briefly ran brown as pressure changed in the pipes.

Lifts and hospitals

Portugal’s civil protection authority (ANEPC) said in January 2026 that more than 400 people had been trapped in lifts. Hospitals ran on backup generators. ANEPC also found that some hospitals were short of generator fuel within two hours, a gap it highlighted as a lesson.

What the investigations found

Two main investigations have now reported.

Spain’s government report (17 June 2025). Energy minister Sara Aagesen said the blackout was caused by overvoltage that set off a chain reaction. The grid did not have enough voltage control capacity that day. Some power plants disconnected when they should not have. The government found no evidence of a cyber attack, though it did find unrelated security weaknesses it promised to fix.

ENTSO-E expert panel final report (20 March 2026). This 440-page report followed an interim factual report in October 2025. It found that several problems combined. These included oscillations on the grid, gaps in voltage and reactive power control, different voltage practices, rapid drops in output and generators disconnecting in Spain. Euronews reported the panel describing it as a “perfect storm” of factors. The report makes 22 recommendations, including better monitoring, closer coordination between grid actors and rules that keep up with a changing power system.

For households, the key point is this: the cause was technical, it was fixed within a day, and no one could have predicted it that morning. That is exactly why a small amount of preparation helps.

Lessons for your household

Here is what made the biggest difference on 28 April, and what official kit lists suggest keeping. The amounts come from the UK government’s Be Ready campaign unless noted.

Item	Why it mattered in the Iberian blackout	Suggested amount
Cash	Cash machines and card terminals stopped working	A mix of notes and coins for a few days of essentials
Battery or wind-up FM radio	Mobile networks were patchy; radio does not depend on them	One per household, plus spare batteries
Torch	Lights went out in homes and buildings	One per person, plus spare batteries
Power bank	Phones need charge to reach family and news	At least one charged bank per adult
Drinking water	Pumps stopped in parts of Portugal	3 litres per person per day (Catalonia suggests at least 1.5 litres)
Food that needs no cooking	Electric hobs and ovens did not work	Enough for 3 days
Medicines	Payments and transport were disrupted	A few days’ supply of essential medicines

Advice on water differs between agencies. The UK says 3 litres per person per day for drinking, while Catalonia’s November 2025 campaign uses 1.5 litres. Ready.gov in the US suggests about 3.8 litres (1 US gallon) per person per day for drinking and sanitation. Our guide on how much water to store explains the difference.

Spain’s own response

In November 2025, the Catalan government launched a campaign asking every household to keep a 72-hour emergency kit near the front door. Its list includes water, a battery radio, a torch with spare batteries, food that keeps, cash, copies of documents, a first aid kit, medicines, a phone charger and a power bank. Officials said the aim was self-protection, not alarm.

What this means wherever you live

Most power cuts are short and local. The Iberian blackout shows that even a modern, connected grid can fail across two countries in seconds, and that the knock-on effects arrive fast: phones, payments, transport and water.

Three habits cover most of the risk:

Keep a little cash at home. Card payments need power and data. See our post on keeping cash at home for emergencies.
Have a way to get news without the internet. A battery or wind-up FM radio is cheap and reliable.
Agree a family plan before you need it. Decide where you will meet if phones fail. Our family emergency communications plan post walks through it.

For lighting, phone power and fridge food-safety times, see our power outage preparation guide. To see how your household’s current supplies compare, check how many days your household would last.

Blackout readiness checklist

Blackouts like this are rare, and a few simple supplies make them much easier to manage. Always follow advice from your local authorities and grid operator.

Sources & further reading

Every fact in this post was checked against the sources listed above on 1 November 2026. Advice changes: always follow your local authorities.