UK Emergency Alert Tests 2025

[DerekC]

It cannot receive an alert via WiFi. The coffee machine probably uses a common Android device as a base, which has a cellular modem. Even if it's not connected to a network and has no SIM card, it can still receive the alert.

OK - that makes sense. I was wondering if the latest coffee machines had a sim card!! Not entirely clear why you would want one with wifi or bluetooth, but that's definitely OT!

 

[RuddA]

My phone is set to WiFi calling and I received it twice, at 15:02 and 15:15.

 

[DerekC]

Light is dawning - the alert isn't sent like a text message. The base station is told to send the message to any phone in its area and continues to do so until the alert is turned off. So when you switch your phone on (or when you enter the area if it's a local alert) you get the message as long as the alert is still set, Does anyone who actually understands how the system works know if that's right?

== Doublepost prevention - post automatically merged: 7 Sep 2025 ==

My phone is set to WiFi calling and I received it twice, at 15:02 and 15:15.

Did you have any cellular signal at all?

 

[RuddA]

Did you have any cellular signal at all?

A single bar, so that must be enough.

 

[Bletchleyite]

I was out for a run and got it. The noise (not excessively loud) played through my AirPods (which I was wearing) rather than the phone.

 

[dangie]

Failure again. Arrived ~15 mins late on many O2 devices, if I remember correctly this is very similar to the last occurrence. On my device, I was curious as to why it didn't go off - so I turned it off and on and only then did it work. So much for being used in an actual emergency...

So if it arrived then it’s a partial success not a failure. After all it was a test not a genuine emergency. Why are there so many negative comments?

Incidently both the wife and I use Tesco Mobile (O2) and both phones alerted together at approx 1501hrs.

 

[JamesT]

Light is dawning - the alert isn't sent like a text message. The base station is told to send the message to any phone in its area and continues to do so until the alert is turned off. So when you switch your phone on (or when you enter the area if it's a local alert) you get the message as long as the alert is still set, Does anyone who actually understands how the system works know if that's right?

https://en.wikipedia.org/wiki/Cell_Broadcast has a description of the technology used, I think your summary is correct. So the variances in when handsets received the alert will be partially on the mobile networks pushing it across their base stations and then how often the handset checks in.

 

[MrJeeves]

Does anyone who actually understands how the system works know if that's right?

I provided a technical explanation of how a device is informed to check for alerts in post #62: https://www.railforums.co.uk/threads/uk-emergency-alert-tests-2025.291684/post-7454792

Essentially, if your phone is connected to the mobile network it will be told to perform a scan for alert informaiton when an alert is sent out.

If you have poor signal and your phone is searching for networks, it will discover the alert as it scans regularly. The device doesn't need to fully connect to the network to see the alert information.

The information is broadcast from all mobile network sites, and to anything that decides to listen. It's not sent to specific devices, hence there's no need for the government to know your phone number or anything else like that.

 

[1D54]

I was on here at 15:00 and got no alert at all.

 

[Siemens Staines]

I did not receive anything which was no real surprise as my phone is too old to support such advanced technology. I did think that I may get a text message as I did get the warning message the other day, but it transpires that it obviously doesn't work like that.

 

[cb a1]

Ah right. Fair enough but the point I was making was that everything else was equal, so for whatever reason O2 took a little longer

Come the apocalypse I’m going to enjoy my 4 extra seconds

My son and I are both on O2. His alert came through about 2 minutes after mine. I then got a second alert another couple of minutes later.

I said to him that O2 clearly think I'm more valuable to society than him so I can be two minutes ahead of him running in whatever direction I need to.

 

[DarloRich]

A total non event. Sound begins, press ok, sound stops. Hardly worth the froth!

I was on here at 15:00 and got no alert at all.

I am sorry, you are not on the list to be rescued.

 

[Purple Train]

I was in a church service. Half the congregation's phones went off at 3, others (including mine) at 3.01, and some poor person's went off at about 3.07. Certainly not as problematic as last time.

 

[Buzby]

My phone went off at 1500, but my 3 cellular connected iPads didn’t - interestingly, it isn’t a text (SMS) message, but uses Cell Broadcast - so it isn’t stored on the device. However, my Apple watch displayed it and that did startle me!

 

[SuspectUsual]

I wish I’d been in a Sam Smith’s pub when this happened

 

[RailAleFan]

....

 

[ainsworth74]

Sound begins, press ok, sound stops. Hardly worth the froth!

I do think it's flawed that pressing okay to make the annoying sound stop also gets rid of the alert text. The instinct is to make the irritating noise stop before you actually pause to read the message. So in a real emergency you'd be at risk of dismissing the very notification you need to read!

Beyond that, as you say, non-event.

I wish I’d been in a Sam Smith’s pub when this happened

Probably for the best really, he'd be liable to have the pub shutdown just because. A really odious individual by all accounts! Though probably a subject fro another thread.

 

[75A]

Between the Wife and I we've got two Tablets and three Android mobile phones, one of the phones got the message bang on 3pm the others all remained silent as we'd set them.

 

[Pete_uk]

Two android phones went off a few seconds apart in our house. One on EE the other on Voda

 

[Jimini]

Random but maybe informative point (although I get the points above about cell based broadcasts): my U.S work phone (AT&T) received the alert at pretty much the same time as my U.K phone (the former roaming on EE; the latter on o2).

 

[PeterC]

I was in a church service. Half the congregation's phones went off at 3, others (including mine) at 3.01, and some poor person's went off at about 3.07. Certainly not as problematic as last time.

Mine wenr off at 15:07 as well (Three) signal inside my house is patchy and variable. SWMBO is in hospital and all the phones there went off over 10 or 12 seconds.

 

[matt]

After not receving it the previous test my phone got it bang on 15:00. This was on three in an area of poor phone signal.

 

[Russel]

Was walking around Lichfield City Centre at 1500, as it was quite busy, it was interesting to see how much variation there was in the time people received the alert, I was hearing it from 1500 until about 1510.

 

[StoneRoad]

I got the warning on Wednesday, but not the actual test message / siren, although OH got both. On the same network and we were sat about a yard apart, at the most !

Was in the pub after eating my Sunday Lunch and at 15:00 and for some minutes after, various phones were warbling ...
a most annoying noise !

 

[Peter Mugridge]

Hmm... doesn't seem particularly annoying to me; I assume it's louder than that on the actual phones?

As expected, mine didn't go off ( turned the alerts off ) but my son's and daughter's phones did ( we were watching the motor race at the time ).

Didn't seem particularly loud, annoying or noticeable, really - as per my thoughts after watching that YouTube video. I can imagine quite a few people are probably going to set it as their ringtone, which will of course reduce the effectiveness of it...

Maybe they should have made the alert sound and volume that of the Carter Sirens?

 

[etr221]

A question: is/was/should the alert/message received by mobile phones without a SIM?

As I understand such phones are still able to make 'emergency calls', is it possible to determine whether they are sufficiently in contact with 'the network' for such purposes?

 

[styles]

A question: is/was/should the alert/message received by mobile phones without a SIM?

As I understand such phones are still able to make 'emergency calls', is it possible to determine whether they are sufficiently in contact with 'the network' for such purposes?

You don't need a SIM to receive it.

I had a cheap Android smart phone with no SIM which went off fine on the last test a couple of years back.

 

[ainsworth74]

a most annoying noise !

I mean that is sort of the point

From memory the tones (which is the same or very similar to the US Emergency Alert System "Attention Tone" broadcast on radio or TV) are deliberately designed to be unpleasant/annoying in the way that they clash in order to get the attention of anyone hearing it. Even if that attention is initially "What is that godawful noise and how to do I stop it?"

I can imagine quite a few people are probably going to set it as their ringtone, which will of course reduce the effectiveness of it...

That seems unlikely to me? Why would people want that particular sound as their ringtone?

 

[greatkingrat]

That seems unlikely to me? Why would people want that particular sound as their ringtone?

Presumably to make other people panic that there is some sort of emergency?

 

[ainsworth74]

Presumably to make other people panic that there is some sort of emergency?

Though you could just play YouTube video if that was your intention as there's plenty examples of the US EAS attention tone (which ours seems to be identical too). No need to set your ringtone as the tone!