All UK mobile phones to receive emergency alert - what you need to do next

Millions of people across the UK will hear a loud siren from their mobilephones in a major test of the emergency alert system.

The "Armageddon alert", which was first trialled in 2023, is sent to phones across the UK to ensure people are aware of a life threatening emergencyin their area, such as a wildfire, severe flooding or extreme storms. Emergency alerts are only sent by the emergency services or government departments, agencies and public bodies that deal with urgent situations.

A national test will take place later this year to ensure the system is working properly. Ministers compared the need to test the alert process to testing a fire alarm in your house.

Similar emergency systems exist in countries like Japan and the US. In Finland, a nationwide test is done every month, while other countries like Germany trial it annually.

A public information campaign will be rolled out ahead of the test, including communications targeted at vulnerable groups, such as victims of domestic abuse. Everyone is urged to keep the life-saving alert switched on but it is possible to opt out if it would put someone at risk.

Here's everything you need to know about the national test of the alert system later this year.

READ MORE: Exact date next Armageddon alarm will go off on millions of phones confirmed

What time will the test take place?

The system will be tested for the second time at 3pm on Sunday, September 7, with Brits receiving a message warning of danger to life nearby. Mobile phones will vibrate and emit a loud siren for around 10 seconds - even if they are set on silent.

A message will also pop up to make clear that this is only a test. There is no need to do anything when the test alert happens, just swipe the message away or click 'OK' on the phone home screen.

When a real alert happens, the message will include a phone number or a link to the GOV.UK website for more information about the emergency. You can see all previous alerts at: https://www.gov.uk/alerts/past-alerts

Why is the test taking place?

Regular testing ensures the system is functioning correctly, should it be needed in an emergency.

Pat McFadden, Chancellor of the Duchy of Lancaster, said: "Emergency alerts have the potential to save lives, allowing us to share essential information rapidly in emergency situations including extreme storms. Just like the fire alarm in your house, it's important we test the system so that we know it will work if we need it."

Who will receive the test alert?

The test will function like a real life Emergency Alert on the approximately 87 million mobile phones in the UK.

Emergency Alerts work on all 4G and 5G phone networks in the UK. Your mobile phone or tablet does not have to be connected to mobile data or wifi to get alerts. However, you will not receive alerts if your device is turned off; connected to a 2G or 3G network; wifi only; or not compatible.

For real emergencies, it depends on where you are and if are affected by a local emergency. Alerts are based on a phone's current location - not where someone lives or works. A person does not need to turn on location services to receive alerts.

Data about people, their device or location will not be collected or shared. The emergency services and the UK government do not need a person's phone number to send an alert.

What should drivers do?

The government says you should not read or respond to an emergency alert while driving or riding, reminding people it is still illegal to use a hand-held device while driving.

People are urged to find somewhere safe and legal to stop before reading the message. If there’s nowhere safe and legal to stop, and nobody else is in the vehicle to read the alert, people can listen to news on live radio to find out about the emergency.

Has the alert been used outside of a test?

The "Armageddon alert" was first trialled across the country in 2023 and five localised alerts have been sent since then to warn of extreme weather.

The largest use was during Storm Eowyn in January,when 4.5million people in Scotland and Northern Ireland got the alert after a red weather warning was issued over risk to life. Some 3.5million people in Wales and the South West of England received an alert during Storm Darragh in 2024, and it has also been used during flash flooding in Cumbria and Leicestershire.

It was also rolled out when an unexploded World War II bomb was discovered in Plymouth in February 2024. Tracey Lee, chief executive of Plymouth City Council, said: "This was the first time the system had been used in a real emergency, and it played a vital role in helping us safely evacuate over 10,000 people and coordinate a complex, multi-agency response."

What is being done to support victims of domestic abuse?

Domestic abuse campaigners have previously warned that the siren could alert abusive partners to someone's secret phone. The government has assured there is the option to opt out of alerts if needed.

The government is continuing ongoing engagement with domestic violence charities and campaigners in the run up to the test, to ensure people know how to switch off alerts on a concealed phone.

How you opt out depends on your device. Full instructions telling you how to opt out are available at: https://www.gov.uk/alerts/opting-out People are advised to contact their device manufacturer for help if they continue to get alerts.

What is being done to support deaf, hard of hearing, blind or partially sighted people?

During the test, audio and vibration attention signals will let people know they have received an alert, if accessibility notifications have been enabled on their mobile phone or tablet.

The government is also continuing ongoing engagement with disability charities and campaigners in the run up to the test.

READ MORE: Join our Mirror politics WhatsApp group to get the latest updates from Westminster