An emergency siren will sound from all mobile phones this weekend, as the UK Government prepares to test its alert system.

The system is designed to warn people if there is a danger to life in the area, such as extreme weather events or other serious emergencies, and has been set off five times since it was launched in April 2023.

At 3pm on Sunday, mobile phones and tablets will vibrate and emit a loud siren sound, even if they are set to silent. A message will also appear, reminding people it is only a test and not to panic.

Regular testing is vital in ensuring the system works properly in the event of a real emergency.

There had been concerns from organisations such as Domestic Abuse charities, that the alerts could potentially alert abusers to hidden mobile phones.

UK Government Emergency Alert system will sound on 7 September, 2025.
It will emit a loud siren-like sound (UK Government)

The Government is therefore reminding people that they can choose to opt out of receiving Emergency Alerts – including national tests – but it “strongly recommends” you don’t.

For more information and advice visit www.gov.uk/alerts