After introducing the UK-wide Emergency Alerts service in 2023, the government is preparing to conduct another nationwide test of the system for all mobile phone users this year. Similar to the previous trial held on April 23, 2023 which notably coincided with the London Marathon – this test will see an emergency warning message displayed on people’s device home screens, accompanied by a vibration and a loud alarm lasting around 10 seconds, even if the phone is set to silent.
We finally have a date and time confirmed for the alert. Here’s everything you need to know.
When will the emergency alert take place?
The test is scheduled for 3pm on Sunday, 7 September 2025. Approximately 87 million mobile devices will receive the alert, including smartphones, tablets, and smartwatches with data plans. Only smartphones operating on 4G or 5G networks will receive the alert; older devices and those on 2G or 3G will not.
What will happen during the emergency test?
Phones will vibrate and emit a loud siren for about 10 seconds, even if set to silent.
A message will appear stating that this is only a test and no action is needed.
An example of what the text message might read: “This is a test of Emergency Alerts, a new UK government service that will warn you if there’s a life-threatening emergency nearby. In an actual emergency, follow the instructions in the alert to keep yourself and others safe. Visit gov.uk/alerts for more information. This is a test. You do not need to take any action.”
Why is this Emergency Alerts system important?
The government is testing the system’s functionality and helping the public become familiar with emergency alerts.
Officials compare the test to a national fire alarm drill. The system is a vital tool for government communication during emergencies, designed to rapidly warn people if there is an immediate risk to life – such as severe flooding, fires, or extreme weather. Emergency Alerts are used very rarely, only in situations where lives are at risk, so months or even years may pass between alerts.
When has the Emergency Alerts system been used before?
Since its launch in 2023, the Emergency Alerts system has been used several times for real emergencies:
Storm Darragh (December 2024): Alert sent to those worst hit by the storm.
Storm Eowyn (January): Around 4.5 million people in Scotland and Northern Ireland received an alert after a rare red weather warning.
Flooding in Barrow upon Soar (January): Residents were told to evacuate due to severe flooding.
WWII Bomb in Plymouth (February 2024): Residents were warned to avoid an area while an unexploded bomb was moved by the military.
How will I receive an emergency alert?
Alerts are broadcast via mobile phone masts; every compatible device in range will receive the alert. The system does not use phone numbers or collect personal data. There is no charge to receive alerts, no sign-up required, and no app to download.
Alerts can be tailored to specific areas, so only those at risk receive notifications. The system uses high-priority signalling, ensuring alerts go through even during network congestion.
What should I do when I receive the Emergency Alert?
When you get an alert, stop what you’re doing and follow the instructions. If driving: do not read or respond to the alert while driving. Find somewhere safe and legal to stop before reading the message.
If you cannot stop safely, listen to live radio for updates until you can. Alerts use audio and vibration signals to ensure people with vision or hearing impairments are notified. Alerts are sent in English and, in Wales, may also be sent in Welsh.
Emergency alerts work on iPhones running iOS 14.5 or later and Android devices running Android 11 or later. Those without compatible devices will still be informed by other official channels.
How to opt out of Emergency Alert tests
Android: Search settings for ‘emergency alerts’ and turn off ‘test alerts’, ‘exercise alerts’, ‘operator defined’ and ‘operator alerts’.
Apple: Go to Settings > Notifications, then scroll to the bottom to toggle ‘Extreme and severe alerts’ on or off.
Different devices: Settings may be named differently, such as ‘wireless emergency alerts’ or ‘emergency broadcasts’.
Alternative: Switch off your device or use airplane mode before the test.
You can find out more about the Government’s Emergency Alerts system here.
Co-written by Alice Lorenzato Lloyd.
