Over 85 million people in the UK will receive an emergency alert on their mobile phones this September.

The test will take place at 3pm on September 7, 2025 and will function like a real-life emergency alert, similar to the emergency test that took place in April 2023.

Devices are expected to vibrate and make a loud siren sound for roughly ten seconds. A text message will also appear on the screen even if the phone is set to silent.

The regular tests are to ensure that the system is functioning correctly, should it be needed in an emergency such as instances of extreme weather.

The emergency alert system was successfully used to aid the evacuation of 10,000 residents in Plymouth last year after an unexploded World War Two bomb was found in a garden.

The alarm was also used to warn 3.5 million people in England and Wales about Storm Darragh.

During the test, personal data about the user, device or location will not be collected or shared.

The emergency services and the UK government do not need a phone number to send an alert.

Similar tests take place in Japan, the United States of America, Finland and Germany.

Emergency Alerts work on all 4G and 5G phone networks in the UK. A mobile phone or tablet does not have to be connected to mobile data or wifi to get alerts.

However, mobile phones that are turned off, connected to 2G or 3G networks or are wifi only will not receive alerts.

Phone-users have been asked by the government to keep the alert on as they contain “life-saving information”, but where you need to turn off the alert, you can do so by visiting: https://www.gov.uk/alerts/opting-out