Wi-Fi and 4G Calling
What is Wi-Fi and 4G calling?
Wi-Fi Calling lets you make and receive voice and video calls over a Wi-Fi connection instead of using your mobile network. If you have a Wi-Fi connection and are in an area where voice service is weak or unavailable, you can use Wi-Fi Calling to continue making calls.
With 4G Calling (also known as ‘VoLTE’), you can make voice calls over the 4G network instead of the older 2G or 3G network. Because 4G has much faster speeds than 2G and 3G, it means your calls connect more quickly and sound even clearer. Anyone with a 4G SIM and compatible handset can use 4G Calling, and calls will seamlessly switch between Wi-Fi and 4G depending on the network available.
Together, Wi-Fi Calling and 4G Calling give you superior call quality and improved coverage range.
How can I set up Wi-Fi and 4G Calling?
As long as you have a 4G SIM and compatible phone, 4G Calling is enabled automatically. For Wi-Fi Calling, find out how to get started by clicking.
How can I tell whether I’m using Wi-Fi or 4G Calling?
If you’re using an Android phone, keep an eye out for the "VoLTE" and "VoWiFi" icons at the top of your screen.
If you’re using an iPhone, there’s no icon to let you know whether you’re connected to 4G Calling. The only way to tell is during a call. If the device displays 4G when you’re taking a call, then that means you’re using 4G calling. But if the device displays 2G / 3G, then the device is using your mobile network.
Does Wi-Fi or 4G calling cost extra?
There’s no extra charge for Wi-Fi or 4G calls, and they’ll come out of your monthly allowance as usual. If you go over your allowance, you’ll be charged your standard out of bundle rates. There will be no change to your monthly UW bill.
How do I know if my handset is compatible?
Our current range of handsets are compatible with Wi-Fi calling and 4G calling. If you bought your device through a third party, it may not be compatible. The best way to check if your device is compatible is to search for ‘Wi-Fi Calling’ or ‘VoLTE’ in your device settings.
Does Wi-Fi Calling work if I’m abroad?
Wi-Fi Calling features only work in the UK.
What determines whether 4G or Wi-Fi calling is used?
Your mobile SIM will automatically select the strongest signal and use that. It will also move between 2G/3G/4G/Wi-Fi Calling if necessary to ensure you get the best signal possible.
They’re both very secure – in fact they’re more secure than traditional 2G and 3G calls. Both 4G Calling and Wi-Fi Calling are carried over IP (internet protocol) as data, which is safely encrypted using IPSec (Internet Protocol Security).
Is Wi-Fi calling or 4G calling better?
Usually, 4G Calling will give clearer calls than Wi-Fi Calling. This is because the mobile network assigns a guaranteed Quality of Service (QoS). With Wi-Fi Calling, the quality of the service is subject to the Wi-Fi / broadband connection.
But where mobile network coverage is extremely weak, Wi-Fi Calling may give a better experience than 4G Calling. For these reasons, devices will typically use 4G Calling over Wi-Fi Calling. Devices will switch to Wi-Fi calling only where there’s no (or very poor) mobile coverage.
Can I call any landline/mobile in the UK?
Yes, there are no restrictions to who you can call using Wi-Fi Calling and 4G Calling.
Will I have access to calling features such as call waiting and voicemail?
There’ll be no change to any calling features.
Can I still call 999?
You can still call the emergency number on 999. However, the emergency services won't be able to identify your location. So, we recommend calling through a fixed phone line when making this call and only using Wi-Fi or 4G Calling as a last resort.
What broadband speeds do I need to use Wi-Fi calling?
You’ll need a minimum speed of 1Mbps to use Wi-Fi calling. But your call quality will be at its best at 2Mbps.