Expect your mobile to go off at 3pm on Sunday as new emergency alerts are tested – here's which phones will ring and what it'll sound like

Public emergency alerts, which will use the 4G and 5G mobile networks, enable urgent messages to be broadcast to a defined area when there is an imminent risk to life, such as wildfires or severe flooding.

Other countries – including Canada, Japan, the Netherlands and the USA – already use the alerts to warn people about severe weather events, for example.

If you're looking for a new handset or Sim, try our Cheap Mobile Finder.

Who will – and won't – get the test alert

Millions of mobile devices connected to any of the UK's 4G or 5G networks will get the alert on Sunday 23 April – but not all.

You WON'T get the alert if your device is:

• Only connected to a 2G or 3G network (not 4G or 5G) – if you have an older device, see our 3G to be turned off MSE News story for more info and help with this. You can also use our Mobile Phone Coverage Checker to see which networks have the strongest signal in your area.

• Wi-Fi only.

• Running an older version of iOS or Android – see which versions are supported and how to check yours.

• Turned off or in airplane mode.

What the alert will look like

Depending on the device you have and its settings, your mobile or tablet may do one or more of the following:

• Make a loud siren-like sound, even if it's set on silent.

• Read out the alert.

• Vibrate.

The sound and vibration will last for about 10 seconds.

Here's what the alert will say:

The video below gives you an idea of how the alerts will appear and sound: 

Charities have warned anyone living with domestic abuse to turn off any hidden phones ahead of the test on Sunday 23 April

The domestic abuse charity Refuge has warned that, because the alerts will sound even if a phone is in silent mode, the test could alert an abuser to a concealed device. Other charities and organisations, including Citizens Advice and local police forces, have shared similar warnings.

If you're concerned about this, you can opt out of the test by switching your phone off before the test at 3pm on Sunday 23 April – unlike a normal text message, the alert won't be delivered after you switch the device back on.

You WON'T be asked for your phone number, location or other details – beware scammers trying to take advantage

The alerts are sent by mobile phone masts, which can broadcast them to compatible devices in the surrounding area during an emergency.

This means the Government does NOT need your phone number, location or any other personal details to send you an emergency alert, and you DON'T need to download an app or sign up to receive them.

Scammers often exploit Government initiatives and other news items as a way to target people – for example, there was a surge in cost of living scams last year as criminals sought to capitalise on the crisis – so be wary of suspicious texts, emails or other messages asking you to hand over your details.

You can opt out of future alerts

If you'd prefer not to get the emergency alerts in the future, you can disable them in the settings on your device – though the Government does advise that you should keep them switched on for your own safety.

To opt out:

1. Search your settings for 'emergency alerts'.

2. Turn off 'severe alerts' and 'extreme alerts'.

3. If you still get alerts, contact your device manufacturer for help.

The Government told us that following these steps should also prevent the test alert from ringing. Alternatively, putting your phone in airplane mode or simply turning it off before 3pm on Sunday 23 April will also do the trick.