Millions of mobile phones across the UK received a loud siren and vibration at around 3pm on Sunday, 7 September 2025, as the UK Government carried out a national test of its Emergency Alerts system.
The alert lasted for around ten seconds and was accompanied by a message on phone screens making it clear that it was only a test.
This was the second nationwide test of the system, which is designed to warn people if there is a danger to life nearby, such as extreme weather. The alerts allow vital information and advice to be sent quickly in an emergency.
Ahead of Sunday’s test, the government ran a public information campaign to make people aware, with particular attention given to vulnerable groups such as domestic abuse victims. The campaign also included materials in British Sign Language.
The government says regular testing is part of its commitment to ensuring the system works as intended and that the public is familiar with it, in line with practice in other countries.
