eSIM WiFi Calling: Get Connected Without Mobile Signal

Using eSIM WiFi Calling gives you coverage even when you don’t have signal.

Ever been on a call and had it cut off because you lost signal after entering a mobile network black spot? Perhaps you live in an area where your mobile coverage doesn’t quite reach? With WiFi Calling this never has to be an issue again.

This nifty functionality keeps you connected in places where mobile signal isn’t available, like the London Underground. Instead of relying on cellular networks you can make and receive calls (and texts) using an internet connection.

In this post, we explore using an eSIM WiFi Calling in more detail, from how it works and how much it costs, to setting it up, compatible devices, and supported networks.

This guide focuses on the United Kingdom

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person making Wi-Fi call in coffee shop

What is WiFi Calling?

With so many ways to get connected, why would you use eSIM WiFi Calling? The answer is simple: It keeps you connected even when you don’t have a mobile signal but doesn’t require an additional app or service.

WiFi Calling is a native functionality (i.e. built into the device) that allows a phone to make or receive calls and texts over the internet instead of cellular networks.

All you need is a supported phone and an internet connection.

How Does it Work?

WiFi Calling works similarly to VoIP applications. It routes the phone call or message through a WiFi connection and across the internet to a cellular network and then to the recipient.

Although the person sending a message or making a call will need a phone that supports the functionality, the person on the other end will only need to be connected to the internet or a cellular service to receive the message or call.

free wi-fi sign painted on wall

How Much Does it Cost?

The good news is that you won’t need to pay any additional data charges.

The service is included in your monthly tariffs whether you have a contract with a carrier or if you’re using a bespoke eSIM plan like the O2 UK eSIM.

If you run out of data, it costs the same as your regular mobile services.

You may need to pay additional data charges if you use it abroad.

Related | What are the different types of eSIMs?

Where Can I Use WiFi Calling?

You can use the service wherever an internet connection is available.

Currently, it is free to use within the United Kingdom and EU, but if you want to use the service outside of those areas additional roaming charges will apply.

woman using Wi-Fi Calling in Underground

How Do I Set WiFi Calling Up?

The functionality isn’t automatically set up on devices so you will need to set it up. The process may be different depending on what device you have.

How to set it up on iPhone

  1. Go to Settings > Phone > Wi-Fi Calling
  2. Toggle the setting to On
  3. To deactivate, toggle the setting to Off

How to set it up on Samsung

  1. Go to Settings > Connections > Wi-Fi calling
  2. Toggle the setting to On
  3. To deactivate, toggle the setting to Off


  1. Go to Phone
  2. Tap the three dots in the top right corner
  3. Navigate to Settings > Wi-Fi Calling
  4. Toggle the setting to On

See | How to activate Wi-Fi Calling on a Galaxy smartphone

How to set it up on Sony

  1. Go to Settings > More > Wi-Fi Calling
  2. Toggle the setting to On
  3. To deactivate, toggle the setting to Off

How to set it up on OnePlus

  1. Go to Settings > SIM & Network > Enhanced Communications
  2. Toggle the setting to On
  3. To deactivate, toggle the setting to Off

How to set it up on Google

  1. Go to Settings > Network & Internet > Advanced > Wi-Fi Calling
  2. Toggle the setting to On
  3. To deactivate, toggle the setting to Off

See | Make calls over the internet on Voice

How to set it up on HTC

  1. Go to Settings > Call
  2. Tap on Wi-Fi Calling to turn on.
  3. To deactivate, uncheck the setting

After it has been activated you won’t need to do anything. The routing of the call or message will automatically use WiFi when you don’t have cellular coverage.

Note: If you don’t see an option for WiFi Calling you may need to update your phone to ensure it is running the latest software.

smartphone home screen with icons

Compatible Phones

There are many handsets that support eSIM WiFi Calling. Unfortunately, this doesn’t guarantee that a network will support the service on that particular device.

Compatible devices vary from network to network (especially Android smartphones) and networks may have limitations on which mobile plans support the service.

Supported Mobile Networks

All the major networks – O2, EE, Three, and Vodafone – support WiFi Calling as well as independent MVNOs like

There may however be compatibility issues or limitations on which devices you can use when using the major carriers. For example, some Android handsets won’t work with Vodafone’s service if you bought it from one of the other networks.

Got questions about using an eSIM Wi-Fi Calling? Planet eSIM is a forum dedicated to answering all your questions about these revolutionary mobile technologies.