Nationwide test scheduled for mobile emergency alert system
The Guardian has reported that the UK government will carry out a second national test of its emergency alert system on 7 September 2025.
The system is designed to notify the public of threats to life, including severe weather events, through mobile phone alerts.
The alerts will bypass silent mode and sound a siren for approximately 10 seconds, displaying a message to indicate that it is a test.
The alert will not be received if a mobile device is turned off or connected to a 2G or 3G network.
There are around 87 million mobile phones in the UK, according to The Guardian.
Alerts used in previous emergencies across the UK
The emergency alert system was first tested across the UK in April 2023.
According to The Guardian, some users reported not receiving the alert, a problem later attributed to certain mobile networks.
Since then, the system has been used regionally on five occasions.
In January 2025, approximately 4.5 million people in Scotland and Northern Ireland received alerts during Storm Éowyn, when the Met Office issued a severe weather warning.
Other local uses include alerts for flash flooding in Cumbria and Leicestershire, and an unexploded Second World War bomb in Plymouth.
Local officials support the system’s emergency response role
Tracey Lee, chief executive of Plymouth city council, commented on the system’s role during a real-life incident.
Lee said: “The alert proved to be an invaluable tool during the Keyham bomb operation.”
“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.”
Government aims to improve coverage and public awareness
The alert system is operated by the UK government and is intended to improve public safety through rapid communication during emergencies.
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.”
The government will provide advance notice of the 7 September test.
This is intended to help vulnerable people, including those affected by domestic abuse who may have concealed phones, to take precautions.
Broader resilience plans and international context
The Guardian reported that McFadden will also present a new resilience action plan alongside the emergency alert system test announcement.
The plan will offer guidance on how members of the public can prepare for different types of emergencies.
Ministers are also expected to release an update on the implementation of the 2023 biological security strategy.
This strategy is intended to support national preparedness for future pandemics.
Other countries such as Japan and the United States conduct regular tests of similar emergency alert systems.
UK emergency alert test scheduled for September 2025: Summary
The UK government will conduct a second nationwide test of its emergency alert system on 7 September 2025.
The alert will sound on mobile phones regardless of whether the phone is set to silent.
Phones switched off or using 2G or 3G networks will not receive the alert.
The system was first tested nationwide in April 2023.
Previous regional uses include severe weather, flash floods and an unexploded bomb.
The government will give prior notice to support vulnerable groups.
Pat McFadden said the test is essential to ensure the system functions in an emergency.
Tracey Lee said the system helped evacuate 10,000 people in Plymouth.
McFadden will also announce a resilience action plan for public preparedness.
An update on the 2023 biological security strategy will also be published.