Cabinet Office claims that ‘vast majority of compatible phones’ received test message

The Three mobile network claims it is now working with government to investigate why a significant number of its users failed receive the test message sent out yesterday by the new national emergency alerts system.

At 3pm yesterday, the system sent messages to all compatible phones across the country. The messages – which were preceded by an alarm-like sound – contained text advising citizens that “this is a test of… a new UK government service that will warn you if there is a life-threatening emergency nearby”.

Alongside a link to a webpage where more information is available, the message added: “In a real emergency, follow the instructions in the alert to keep yourself and others safe. This is a test you do not need to take any action.”

There have been widespread reports that many customers of the Three network did not receive the message. The company acknowledged the issue and said that it was now engaging with government to investigate the problems, ahead of the full launch of the platform for sending alerts about ongoing emergencies.

“We’re aware that a number of customers have not received the test alert,” Three said. “We’re working closely with the government to understand why and ensure it doesn’t happen when the system is in use.”

The Cabinet Office, which is managing the alerts platform, said that “the vast majority of compatible phones received the alert, [but] we are aware that a very small proportion of mobile users on some networks did not receive it and will be looking at this as part of our review of the test”.

A spokesperson for the government added: “We have effectively completed the test of the UK-wide Emergency Alerts system, the biggest public communications exercise of its kind ever done. We are working with mobile network operators to review the outcome and any lessons learned.”

Three – whose network also supports connections from so-called ‘piggbyback’ providers SMARTY, iD Mobile, FreedomPop, and Superdrug Mobile – is the smallest of the UK’s four network providers, accounting for about one in seven connections. The largest of the four is O2 which, including piggyback networks such as Virgin Mobile and Giffgaff, accounts for more than a third of all connections. EE holds the second-largest market share, ahead of Vodafone in third.

To support the rollout of the alerts system, between December 2020 and May 2021 the government signed five-year deals with each of the four UK mobile network operators. A cumulative total of £15.6m was spent on the contracts, including a £3.6m deal with Three.

The system is designed to send messages to all 4G- and 5G-connected phones within range of designated network masts. Alerts will be issued in circumstances where there is considered to be an imminent threat to life or safety – primarily from extreme weather, such as heat, cold, storms, or wildfires.