Emergency alert system test 2025: Dates, time and what will happen - who will receive the 'siren' phone alert?
Millions of phones are set to sound next month as the emergency alert system test take place.
The emergency alert system has already been used throughout the UK in order to deliver vital messages to at-risk residents. For example, the system have previously been used to send urgent weather warnings to millions of people in Scotland and Northern Ireland as Storm Eowyn touched down in January 2025.
Millions of residents in Wales and south-west England were similarly alerted when Storm Darragh tore its way through the country in December 2024. Meanwhile, the system was used on a more local population in Plymouth in February 2024, when residents were alerted to an exploded World War II bomb found in a back garden.
The upcoming test has been labeled as “one of the biggest public safety exercises in our nation’s history” by cabinet minister Pat McFadden.
When will the emergency alert system test take place?
The next test for the emergency text alert system will take place at 3pm on Sunday, September 7.
What happens during the emergency alert system test?
At the start of the test, mobile phones around the UK will sound with a ‘siren’ noise and vibrate for up to 10 seconds, even if your mobile phone is set to silent. This will be delivered to phones alongside a text message which will clearly indicate that the alert is a test only.
The message will read: “This is a test of Emergency Alerts, a UK Government service that will warn you if there’s a life-threatening emergency nearby. You do not need to take any action. In a real emergency, follow the instructions in the alert to keep yourself and others safe. Find simple and effective advice on how to prepare for emergencies at gov.uk/prepare.
“Visit gov.uk/alerts for more information or to view this message in Welsh. Ewch i gov.uk/alerts am ragor o wybodaeth neu i weld y neges hon yn y Gymraeg.”
Who will receive the emergency alert system test message?
Mobiles phones connected to the UK’s 4G and 5G networks will be sent the test message. This means that UK residents who are abroad or who do not have connection to 4G or 5G networks will not receive the message.
The message will not be delivered to devices which have been turned off or are in airplane mode. Wi-Fi-only devices such as tablets will not receive the emergency alert.
The majority of mobile phones are expected to receive the alert, with more than 80 million phones set to sound.