At exactly 3pm on Sunday, September 7, 2025, a piercing siren erupted from millions of mobile phones across the United Kingdom, signaling the UK government’s second nationwide test of its emergency alert system. For most, it was a brief interruption—just ten seconds of noise and vibration, followed by a message reassuring recipients that it was only a drill. But for others, the event carried far more serious implications, raising questions about safety, accessibility, and the balance between public good and private risk.
The test, which built on the first national drill conducted in 2023, was designed to ensure that the system works seamlessly in the event of real-life emergencies. According to government estimates, nearly 100 million devices were expected to receive the alert, with about 95% of the UK population having access to the necessary 4G or 5G networks. The message, broadcast in both urban centers and remote corners—from London’s bustling streets to the windswept cliffs of Land’s End—read: “This is a test of Emergency Alerts, a UK government service that will warn you if there’s a life-threatening emergency nearby. You do not need to take any action. In a real emergency, follow the instructions in the alert to keep yourself and others safe.”
Prime Minister Sir Keir Starmer hailed the exercise as a vital step in national preparedness. “This is an important step in keeping people safe during national emergencies,” he said, as reported by BBC. Government officials, including Pat McFadden, Chancellor of the Duchy of Lancaster, emphasized the system’s life-saving potential. “It is a vital tool for keeping the nation safe when lives are on the line – and every minute matters,” McFadden noted. He pointed to recent real-world deployments of the system, such as warnings during Storm Darragh and Storm Eowyn, and the evacuation of 10,000 Plymouth residents following the discovery of a 500kg unexploded Second World War bomb.
The system’s ability to target specific regions has proven crucial. For instance, 3.5 million people across Wales and south-west England were alerted during Storm Darragh in December 2024, while 15,000 phones received warnings during flooding in Cumbria in May 2024. “During Storm Darragh and Storm Eowyn, as millions faced dangerous extreme weather, I saw first-hand how effective it was at getting life-saving advice to at-risk communities in an instant,” McFadden said. The technology can pinpoint areas of risk, ensuring that only those who need to act are notified, thus minimizing unnecessary panic.
Despite the system’s intended benefits, the test was not without its challenges. Some users reported receiving garbled messages, but a government spokesperson asserted that “the alert message was broadcast correctly and mobile operators have confirmed that the test ran as expected,” with no evidence of widespread errors. Others were startled by the sheer volume of the siren, which cut through the silence of libraries, woke up pets, and even startled passengers on the London tube. The alert’s reach was impressive—one aviation enthusiast received the alert while a couple of thousand feet up during a flying lesson in Kent, a testament to the system’s broad coverage.
However, as the test unfolded, concerns surfaced about unintended consequences, particularly for vulnerable groups. Domestic abuse charities such as Refuge and Solace raised alarms that the alert could inadvertently expose victims hiding secret phones from their abusers. Emma Pickering of Refuge explained, “During the initial roll-out of the government’s emergency alert system, Refuge expressed concerns about how the alerts could indirectly impact survivors who have hidden devices by making their abuser aware of the device. We know that having a hidden device that can be used to access support without fear of being tracked can offer a lifeline for many survivors.” A Solace spokesperson echoed these worries: “These alerts may put domestic abuse survivors at risk, if they are concealing devices from perpetrators.”
To address these risks, detailed instructions circulated on how to disable emergency alerts. For iPhone users, the process involved navigating to the ‘notifications’ menu in settings and toggling off ‘severe alerts’ and ‘extreme alerts’. Android users could search for ‘emergency alerts’ in their settings and do the same. For other devices, the government and charities provided step-by-step guides, including video tutorials on Refuge’s YouTube channel. The government also clarified that operator test alerts could be opted out of via network settings.
Of course, not everyone received the alert. Devices needed to be switched on, connected to 4G or 5G, and running relatively recent software—iOS 14.5 or later for iPhones, and Android 11 or later for Android devices. Phones on older 2G or 3G networks, WiFi-only tablets, or those switched off or in airplane mode missed the alert entirely. While this spared some from the sudden blare, it also highlighted a vulnerability: in an actual emergency, those without compatible devices or up-to-date software could be left in the dark. This gap is not trivial, especially for the elderly or those unable to afford newer technology.
Sporting events, public gatherings, and even a rugby match were momentarily disrupted as the siren sounded nationwide. Some drivers received warnings, and in places where silence is golden—like the British Library—the alert’s intrusion was met with confusion and, occasionally, humor. Yet, as the government pointed out, “It’s a small price to pay for a system that could one day help save lives.”
While the test was generally deemed a success, the government acknowledged the need for ongoing assessment. “We’re carrying out the test to make sure the system works well when we need it most, and afterwards, we’ll work with mobile network operators to assess performance,” McFadden said. The government stressed that emergency alerts are just one piece of the puzzle; in real emergencies, warnings would also be broadcast via television, radio, and even door-to-door notifications in some cases.
As the UK reflects on this latest test, the conversation continues about how best to balance technological progress with inclusivity and safety. The emergency alert system, like a fire alarm, may be disruptive in the moment, but its potential to save lives is undeniable. Still, as campaigners, technologists, and policymakers debate the finer points, one thing is clear: the siren’s echo has prompted a nation to think more deeply about what it means to be prepared—and protected—in a rapidly changing world.
