Mobile phone alerts in the United Kingdom


Settings for emergency alerts on UK devices

The United Kingdom's mobile phone alert system is an emergency population warning system currently in development that uses cell broadcast.[1] Early testing began in 2014, with the first test alert sent in March 2020.[2] The system is intended for use for major crises such as flooding or terror attacks.[3]


During the Cold War, the UK developed an emergency alert system called the Wartime Broadcasting Service, aimed to keep UK residents informed after a catastrophic wartime attack, such as a nuclear warhead detonation or severe bombing.[4]

The state of this system is currently unknown to the public, and most information about it is held exclusively by BBC high-ranking executives and government officials.

Early cell broadcast trials

In 2013, the Government of the United Kingdom trialled a system similar to other countries in which cell broadcasts would be simultaneously broadcast to multiple mobile devices.[5] The final project report in 2014 found that "Responders remain very keen to see the implementation of a national mobile alert system" and that "the majority of people (85%) felt that a mobile alert system was a good idea." The report said it was the hope to carry out more trials, however past that point no further trials were conducted. An earlier 2012 report ("Extended Floodline Warnings Direct Trial") by the Cabinet Office using mobile phone calls found that only 12% of recipients acknowledged the alert.[6] During the COVID-19 pandemic in the United Kingdom, the government was accused of ignoring its own advice to set up UK emergency alert system and how after seven years of the Cabinet Office's own report showing such systems were successful, there was "no sign of a system being developed."[7]

In 2019 and early 2020, the Environment Agency collaborated with EE, Fujitsu and The University of Hull to trial Cell Broadcasting technologies for the purpose of flood warning.[8][9]

Cell broadcast trial and implementation

An emergency alert example as published by the British Government.

In 2020, the UK began developing an emergency alert system using Cell Broadcast in collaboration with UK mobile networks.[3]

In March 2021, a test across all networks on the test channels took place in Reading with the British government's Flood Information Service updating a page on its website, stating that the new cell broadcast system is being tested, and some devices may receive test alerts. This page was updated again in April for further operator tests.[10][11]

A test broadcast was made for customers on O2 on 11 May 2021 at around 8 am to users who had enabled test alerts in their phone's Wireless Alerts settings.[2] A similar trial was run on the 20 May for EE customers. Two alerts were sent, received at around 13:21 and 13:48 respectively.[citation needed]

The first test on the public channels for the new Emergency Alerts System was on the 25th of May in East Suffolk, the second test of the system was on the 29th of June in Reading,[12] before being rolled out with an introduction Emergency Alert nationwide in early 2022.[13][14] The system is guaranteed to work on iOS 14.5 and later, and on Android 11 and later, though if Wireless Alerts settings are available on older Android devices, the alerts are very likely to work on those, too.[15][16] Since the majority of Android devices are already compatible with Cell Broadcast alerts such as the USA's WEA system, most older Android devices should also be compatible.[17]

The alerts will only be available on devices that connect to the UK's 4G and 5G networks, and not 2G or 3G,[16] despite Cell Broadcast being part of the GSM specification since before 2G adoption was widespread in the UK.

Coronavirus (COVID-19) pandemic

On 24 March 2020, the government collaborated with all UK mobile networks to send a text message to inform people of the new lockdown rules.[18]

Text message sent to all UK mobile numbers when the first UK lockdown began.

On 26 December 2021, the government sent another nationwide text message to inform the population about the availability of COVID-19 booster vaccinations, available for free through the NHS.[19]

Text message from the UK Government's NHS informing about booster vaccinations to defend against the Omicron variant of COVID-19.

See also


  1. ^ "The National Attack Warning System". Civil Defence today. Retrieved 18 April 2021.
  2. ^ a b Hughes, Matthew. "Rude awakening for O2 customers after network runs surprise test of emergency mobile alert system". Retrieved 18 May 2021.
  3. ^ a b Woods, Ben (15 February 2021). "Testing of mass text alert system to flag viruses will begin next month". The Telegraph. ISSN 0307-1235. Retrieved 18 May 2021.
  4. ^ "The BBC's detailed plans for nuclear war". BBC. 23 July 2016. Retrieved 26 December 2021.
  5. ^ "Public emergency alerts: mobile alerting trials". GOV.UK. Retrieved 18 April 2021.
  6. ^ Extended Floodline Warnings Direct Trial (PDF) (Report). May 2012. Retrieved 18 April 2021.
  7. ^ "Government ignored advice to set up UK emergency alert system". The Guardian. 23 March 2020. Retrieved 18 April 2021.
  8. ^ "Floods". TheyWorkForYou. Retrieved 22 April 2021.
  9. ^ "U.K. Developing Targeted Mobile Broadcasts for Virus Alerts". 27 August 2020. Retrieved 21 April 2021.
  10. ^ "Local emergency alert trials - GOV.UK". Retrieved 9 May 2021.
  11. ^ "Local emergency alert trials - GOV.UK". 25 April 2021. Archived from the original on 25 April 2021. Retrieved 9 May 2021.
  12. ^ "Planned tests". GOV.UK. Retrieved 12 June 2021.
  13. ^ "New emergency text alerts to be trialled". BBC News. 17 May 2021. Retrieved 18 May 2021.
  14. ^ "Emergency Alerts". GOV.UK. Retrieved 18 May 2021.
  15. ^ "Switching on emergency alerts this summer". Retrieved 18 May 2021.
  16. ^ a b "How emergency alerts work". GOV.UK. Retrieved 18 May 2021.
  17. ^ "Emergency phone system to send warnings of terror attacks by text message". The Independent. 15 May 2021. Retrieved 28 May 2021.
  18. ^ "Coronavirus: SMS messages". GOV.UK. Retrieved 18 May 2021.
  19. ^ "Get Boosted Now text message to go out from Boxing Day - GOV.UK".

External links

  • Official website
  • Public emergency alerts: mobile alerting trials