WiFi calling guide:
the UK mobile networks with the best schemes
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Our guide talks you through which UK mobile networks have WiFi calling, compares how each scheme works and the phones they support. SIM Sherpa is your trusty guide. Last updated: April 7th 2020
In our WiFi calling guide
How WiFi calling works
Mobile network rankings
SIM only deals
How WiFi calling works
What is WiFi calling and what are its benefits?
✔ Stay connected when there's no mobile signal
WiFi calling is a network feature, which lets your phone use WiFi signal to make/take calls and sometimes also send/receive SMS text messages, instead of conventional mobile signal.
The advantage of this is straightforward: if you’re in an indoor blackspot that mobile signal can’t get to, like underground or in a thick-walled building, you can still use your phone if there’s WiFi there.
When you make a call or send a text over WiFi calling, it comes out of your regular mobile allowance (or it's charged at your normal rate on pay as you go). People calling you just dial your usual mobile number.
At the moment, WiFi calling is only offered by a few networks in the UK (see further down page). And it's mostly the big 4 providers where you can get it. But some of the smaller ones are just starting to offer it too.
What we think makes a good WiFi calling scheme...
✔ The easiest, most-accessible scheme will win
Below, we've listed all the networks that have WiFi calling and ranked which ones we think have the best schemes. The best WiFi calling scheme will…
1) Make and take high quality calls without making you do anything differently
2) Allow you to send and receive conventional SMS text messages too
3) Let you move away from WiFi mid-call without dropping your call
4) Work with as many makes and models of phones as possible
We’ve looked at every network’s schemes and ranked them on how well they live up to all this.
Where to next within this guide?
UK mobile networks with WiFi calling
Here are the only networks with WiFi calling schemes
Click a logo to see our rankings or read in order
1st place: Three's inTouch WiFi calling is the most flexible
What we like:
Comes as standard on any plan Supports SMS text messages too Move away from WiFi without call dropping Worked on test phones not bought from Three
What we don't like:
App for unsupported phones withdrawn
Three's conventional 3G signal for calls and texts is broadcast on frequencies that can find it difficult to get into buildings (read our indoor coverage guide here), so thankfully their WiFi calling scheme is excellent.
WiFi calling on Three should just work automatically out of the box, with no rummaging in your account to activate it. And every plan comes with it. Three are the only network with WiFi calling on pay as you go.
Each of these deals comes with Three's inTouch WiFi calling:
Three are the most confident network about supporting your phone (see device list here), as long as the handset has the feature . Our manufacturer-bought Android test phones worked with Three's WiFi calling.
They did withdraw an external app for unsupported phones, which annoyed quite a few people. But overall, the flexibility of Three's inTouch is what earns it its place at the top of our rankings.
Useful link: How to get WiFi calling on Three
Joint 2nd: BT Mobile's WiFi calling has improved hugely
What we like: Comes as standard on any plan Supports SMS text messages too Move off WiFi without dropping call Combine with free BT WiFi
What we don't like: Non-committal on some Android phones
BT Mobile find themselves in a similar situation to Three with their 2G and 3G signal for calls and texts not being broadcast on ideal frequencies to get good indoor signal. So their WiFi calling needs to be good.
And it is. It should work from the moment you put their SIM card in a WiFi calling-ready phone. Every BT Mobile plan gets you WiFi calling as standard. And you can send / receive SMS text messages with it too.
BT say they can't guarantee support for Android phones not bought from BT. We think they're covering their backs a little. Our test Android phones weren't bought from EE/BT but the feature worked fine on them.
Each of these BT Mobile deals gets you WiFi calling as standard:
One bonus point with BT Mobile is that you get free access to millions of public BT WiFi hotspots too, which complements the feature by extending WiFi calling to places out of the home too.
Useful link: All about BT's WiFi calling scheme
Joint 2nd: EE’s WiFi calling now supports more phones
What we like: Huge list of supported phones Supports SMS text messages too Move off WiFi without dropping call Combine with WiFi on the Underground
What we don't like: Not available on Flex or pay as you go
EE have clearly been working with manufacturers to get their WiFi calling settings included with software updates, because their supported device list is now huge, even if you didn't buy your phone from EE.
You get WiFi calling as standard on any phone contract if the model has the feature or on their 12-month or longer SIM only deals. You don't get it on Flex SIMs or pay as you go though.
These are the best current EE SIM only deals that get you WiFi calling:
In terms of its functionality, EE's WiFi calling is as good as Three and BT's. You can send and receive SMS texts over WiFi and you can move away from WiFi mid-call without it dropping, as long as you have 4G signal.
As long as you're not looking to join on pay as you go, EE deserve their place on your shortlist for networks to join with WiFi calling.
Useful link: Read what EE say about their WiFi calling
Joint 2nd: iD Mobile only budget network with WiFi calling
What we like: Big list of supported phones Supports SMS text messages too Move off WiFi without dropping call Cheap plan prices
What we don't like: Not available on pay as you go
It's very unusual for low-cost networks to offer WiFi calling. But iD Mobile do. And we actually rate it highly - because we suspect it's basically identical to Three's system, from our own tests.
You can send and receive texts over WiFi and you can switch over to a 4G call too if you move away from a WiFi connection, without the call dropping.
Their list of supported devices has grown substantially recently iD seem more confident you can bring a phone from another network to them, and WiFi calling will work. Our manufacturer-bought Samsung worked on iD.
These are the most competitive current deals with WiFi calling on iD Mobile:
The only real things stopping us giving iD a higher rating are that you don't get it on their pay as you go, and they don't offer any free WiFi hotspots to combine with (like London Undergroun).
Useful link: Read iD Mobile's guide to their WiFi calling
3rd: O2 WiFi calling doesn't support SMS texts
What we like: Move away from WiFi without getting cut off Combine with free O2 WiFi
What we don't like: Non-committal on Android phones Doesn't work on pay as you go
If your primary interest in WiFi calling is to make and take phone calls over WiFi, then O2 are a perfectly good choice. But it's worth noting they don't support SMS text messaging over WiFi, like the networks above do.
We also find it a bit tedious that you have to go into your account and manually turn on WiFi calling. But once you do, the feature works well, connects quickly, with decent audio quality.
You can only get WiFi calling on O2's pay monthly phone contracts and SIM only deals. It doesn't work on their pay as you go products, which is an unnecessary restriction.
Here are our favourite current O2 SIMs with WiFi calling:
O2's list of supported devices has been steadily growing. And even though they say you may need to have bought an Android phone from them, we found our manufacturer-bought Samsung worked fine.
Useful link: Read O2's full guide to WiFi calling
Joint 4th: Vodafone’s WiFi calling supports loads of phones
What we like: Disconnect WiFi without call dropping Good support for iPhones
What we don't like: Patchy Android phone support Doesn't support SMS text messages Not on pay as you go or Basics
As one of the main four networks, it's a must that Vodafone have WiFi calling. And they do. Although you only get it Red and Unlimited pay monthly phones and SIMs (Basics Plans and pay as you go don't include it).
Functionality-wise, Vodafone's WiFi calling is good. We found calls connect fast with good audio quality. And you can lose the WiFi signal without the call dropping if you're in a 4G area. It doesn't work with SMS texts.
We'd say Vodafone are the riskiest network to try joining on SIM only with an Android phone not bought from them. Our manufacturer-bought Samsung Galaxy S7 didn't work, despite being on their supported device list.
Here are the best-value plans on Vodafone that include WiFi calling:
If you have an iPhone or take an Android on a phone contract directly from Vodafone, then the feature should work. Vodafone are a viable choice, as long as you test WiFi calling, as soon as your product arrives.
Useful link: Full details on Vodafone's WiFi calling
Joint 4th: Sky Mobile offer WiFi calling on select devices
What we like: Comes as standard on any plan iPhone support good
What we don't like: Android phone support patchy Doesn't support SMS text messages Didn't transfer to 4G calling mid-call
Sky Mobile don't make a huge song and dance about having WiFi calling but they do have it. And you'll get it free as standard on all their plans (phones and SIMs).
If you're taking a phone contract for a device that has the feature, WiFi calling will work on Sky. If you're taking a SIM only and bringing a phone from elsewhere, there are some compatibility issues.
These are the current best-value plans on Sky Mobile that also include WiFi calling:
If your phone's an iPhone, the feature should work. If it's an Android, check Sky's latest supported device list here, because our own testing found if your phone's not on there, the WiFi calling feature genuinely won't work.
We found Sky Mobile's WiFi calling only "kicks in" when there's no signal for a 4G calling call. When wemoved away from WiFi connections during a call, the call dropped too (handover to 4G calling / VoLTE failed).
It just means you have to stay put if you're on a call. Overall, the audio quality and connection time is good. And if it works, it works. So Sky Mobile are a viable option if you need the feature.
Useful link: Sky Mobile's WiFi calling help guide
5th: Virgin Mobile now offer WiFi calling for limited models
What we like: Good iPhone support (update needed)
What we don't like: Limited Android support No 4G calling yet Calls drop when out of WiFi range
Virgin Mobile added WiFi calling to all their pay monthly plans from April 2020, meaning you can now make and take calls over WiFi calling, as long as your phone is supported and you've had the latest software update.
Their list of supported devices is limited but does include all iPhone models with the feature (you'll need latest iOS update) and some Androids. We've successfully tested it on an iPhone 7 but our older Samsung didn't work, as Virgin predicted.
Here are the best-value Virgin Mobile SIM only plans that come with the WiFi calling feature:
The technology kicks in easily when you're on WiFi and calls are fast to connect and decent quality. We were able to send outbound SMS text messages over WiFi but not receive them in our tests.
It doesn't look like Virgin have actived 4G calling though, which means no expanding calls coverage and that you can't move away from an area with WiFi without the call dropping like you can with other providers.
Useful link: How to activate WiFi calling on Virgin Mobile
Joint last for WiFi calling: all other UK mobile providers!
✖ No WiFi calling with these providers
As you can see from above, WiFi calling is really only possible on the 4 major providers that control their networks and a handful of smaller providers that piggyback on them.
This means WiFi calling is still actually a bit of a premium feature, as the main networks tend to be a little pricier than their smaller counterparts. The question is how much you value it.
Notable virtual networks that don't have WiFi include: Tesco Mobile, giffgaff, VOXI and SMARTY. It'd be good to see these providers offering it in future.
Where to next within this guide?
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WiFi calling FAQs
What does WiFi calling mean?
WiFi calling is when your phone uses a WiFi signal to make or take a call instead of conventional mobile phone signal.
Which UK mobile networks have WiFi calling?
The only networks currently offering WiFi calling are BT Mobile, EE, iD Mobile, O2, Sky Mobile, Three and Vodafone.
How do you test if WiFi calling is working?
On most phones and networks, you'll see a symbol at the top of your screen showing a phone with WiFi coming from it, or the words "WiFi calling" or similar.
You'll find some networks' WiFi calling kicks in more easily than others. You might need to try get somewhere without phone signal. Try the middle of your house, in a cupboard, or putting your phone on the floor to get it to kick in.
When you make the call, most phones will indicate it's a WiFi call on the phone call screen.
What shall I do if my WiFi calling isn't working?
If you don't think WiFi calling is working, we'd recommend the following:
1) Make sure your phone actually has the feature, by checking the manufacturer website
2) Make sure your network has the feature and you're on a plan that includes it
3) Check in your mobile network account that the feature is turned on (it can be set to off on by default on some networks)
4) Dig into your phone settings to make sure WiFi calling is turned on as a feature (switching between networks can turn it off)
5) Download the latest software update for your phone
6) Seek help from your mobile network and return your SIM within their 14 days period if all else fails and you've bought online
How much does WiFi calling cost?
On every network that offers it, calls made via WiFi calling will cost the same as if you'd made them over a mobile phone signal.
If you're on pay monthly, WiFi calls will come out of your monthly allowance of UK minutes. If you have unlimited minutes, then there's no limit on WiFi calls either.
If you're on a pay as you go, WiFi calls are charged at the same rate as regular ones.
Can you use WiFi calling abroad when roaming?
Generally speaking, no you can't. One exception to this was O2's TuGo WiFi calling app, which did let you call from abroad but has now been discontinued.
As far as we know this is more of a technological limitation than a choice by the mobile providers themselves.
An alternative to using WiFi calling would be using an app like Facebook Messenger, WhatsApp or Skype over WiFi instead while you're roaming.
It's worth remembering that every mobile network now has to offer free roaming within the EU (read our guide to best roaming networks here).
Do you need an app for WiFi calling?
Out of the mobile networks that offer WiFi calling, most work via software on your phone, which connects automatically in the background when you've got better WiFi signal than mobile signal. That means you don't need to run a separate app manually to be able to make a call.
On the other hand, the networks that receive our best ratings offer an optional separate app if your phone is not compatible with their main software.
What’s the data usage with WiFi calling?
WiFi calling doesn't use up any of your mobile data because you connect to it via WiFi rather than by 3G or 4G mobile signal. Data usage with WiFi calling isn't something to worry about.
Which phones support WiFi calling?
Generally speaking WiFi calling came in as a phone feature in the years since 2015 but only on particular models (particularly iPhone and high-end Samsung Galaxy).
To make things more complicated, different networks' WiFi calling schemes support different devices. The best choice is to check the published lists of support phones for each of the networks to see if yours is covered:
EE | iD Mobile | O2 | Three | Vodafone | BT Mobile| Sky Mobile
How good is WiFi calling sound quality?
According to all providers, the answer to this is dependent on the quality of your WiFi signal. None of the networks make any hard and fast promises of HD quality for WiFi calling.
Can you also receive calls on WiFi calling?
Yes. When your phone's connected to WiFi calling, it's just like it being on normal mobile signal, so you will be able to receive calls on your regular mobile number.
