flame Compare Deals and save hundreds of pounds Sim Only Deals Phone Deals

What is VoLTE?

VoLTE

VoLTE stands for voice over LTE and it’s more or less exactly what it says on the tin. It's voice calls over a 4G LTE network, rather than the 2G or 3G connections which are usually used.

We tend to think of 4G as mostly being about downloading, streaming and web browsing, and indeed that’s primarily what it’s been used for so far, but it can also be used to improve calls, which is why some networks have started offering VoLTE.

Below you’ll find everything you need to know about VoLTE, including which networks offer it and what’s so good about it.

What are the benefits of VoLTE?

  • Superior call quality

The big advantage of VoLTE is that call quality is superior to 3G or 2G connections, as far more data can be transferred over 4G than 2G or 3G. Up to three times as much data as 3G and up to six times as much as 2G to be precise, making it easier to make out not only what the person on the other end of the line is saying, but also their tone of voice.

Essentially it’s an HD voice call and it’s a much richer experience overall.

  • Improved coverage and connectivity

VoLTE can connect calls up to twice as fast as the current methods, and as 2G and 3G connections will still be available when there’s no 4G signal it simply means that there’s greater mobile coverage overall, as without VoLTE you wouldn’t be able to make or receive calls in places with a 4G signal but no 2G or 3G.

Three_Super_voice

You might think that would be a rare occurrence, but some of the frequencies that 4G operates on, such as the 800MHz spectrum, have far greater reach than 2G or 3G spectrum, so you’ll be able to get signal further away from a mast or in buildings which other signals struggle to penetrate. Indeed, Three is fully relying on its 800MHz spectrum for VoLTE calls.

However, while 2G and 3G services have largely remained so far they aren’t as necessary as they used to be, and much of the spectrum used for 2G in particular could potentially be repurposed to increase capacity on 4G or 5G networks.

  • Better battery life

Smartphone users could also find their battery life increased with VoLTE, as without it whenever you make or receive a call your phone has to switch from 4G to 2G or 3G, since 4G calls aren’t supported, and then once the call is finished your phone switches back again. All that switching, plus the need to search for a different signal each time, can give the battery a significant hit.

  • Faster data

As you don’t have to switch to 3G when making a call with VoLTE, that means you can also keep using 4G for other functions on your phone while on a call. That’s handy if you’re multi-tasking. For example, browsing the web at the same time or downloading an app.

  • Works with Wi-Fi

4G Calling also offers the ability to seamlessly move between that and Wi-Fi Calling, without the call cutting out, so if you move away from one signal type you can continue on the other.

  • Video calling 

It’s also theoretically possible to make video calls over 4G, much like a Skype call, except you’d just use your mobile number and be able to use the regular dialler and call interface, so you can make and receive video calls from anyone else with VoLTE, rather than relying on separate accounts.

In fact you may have noticed that Skype and other existing video call services often seem to have superior audio quality to voice calls. That’s because like VoLTE they use more data as part of a similarly named VoIP system, so you can expect your voice calls to sound more like Skype calls when using VoLTE, but they won’t hit your battery life as much as Skype does.

Not only could video calls become native to the dialler, but other Rich Communication Services (or RCS’s) could as well, such as file transferring, real time language translation, and video voicemail, and there may be applications which haven’t even been thought up yet.

However, it’s worth noting that at the moment RCS is only used for messaging, and even then not by every network or smartphone maker – with Apple for example not yet supporting it, so this potential of VoLTE hasn’t yet been widely explored.

Are there any limitations to VoLTE?

It’s not available everywhere on every network, or on every handset, so you may or may not be able to use VoLTE – we’ve got more information on that below.

But assuming you can use it the only real limitation is that it won’t work when abroad.

Who offers VoLTE in the UK and how do I get it?

All the major UK operators offer VoLTE along with a few MVNOs (mobile virtual network operators).

In order to take advantage of VoLTE you need to ensure your phone is compatible and that coverage is available (though VoLTE works in most of the same places as 4G), so we recommend checking on the links provided to make sure you will be able to take advantage of VoLTE (4G Calling).

Assuming you have a compatible phone, the latest software from your network and are in an area with VoLTE on any of these networks you should have access to VoLTE – it may not be available on all plans though and the availability regularly changes, so if in doubt check with your network.

UK Networks offering VoLTE

Network

Availability

EE

Check compatibility

O2

Check compatibility

Three

Check compatibility

Vodafone

Check compatibility

iD Mobile

Check compatibility

BT Mobile

Check compatibility

Sky Mobile

Check compatibility
  • Three

Three was the first and network to offer VoLTE, through a service dubbed 4G Super-Voice, which is widely available across the UK.

A large number of phones are compatible if bought direct from Three including the Samsung Galaxy S20 range, iPhone 11 range, Samsung Galaxy S10 range, Huawei P30 Pro, Xiaomi Mi Mix 3 5G, iPhone X, iPhone 8, Samsung Galaxy S8, Samsung Galaxy Note 8, LG G6, Sony Xperia XZ Premium, Huawei P10 and many more.

  • EE

EE has a VoLTE service called 4G Calling, which is available everywhere on EE’s 4G network.

The service is only available on certain phones (and the selection is even more limited if you didn’t buy direct from EE), but many of the latest and most high-profile handsets are supported. 

  • Vodafone

Vodafone also has a VoLTE service called 4G Calling, and it’s available in the same places as its 4G network.

The service works with most high-profile phones from Apple, Samsung, Huawei, and Sony, among some others, but with the exception of Apple phones you must have bought your handset from Vodafone for 4G Calling to work on its network.

  • O2

O2’s VoLTE service is also called 4G Calling, and it’s available in many cities across the UK, on a range of handsets from Apple, Samsung and Sony, plus a small number from OnePlus, Google and others. However as with most networks, some Android phones only work with it if bought direct from O2.

  • iD Mobile

iD Mobile offers VoLTE in the same locations as Three, so it’s widely available. It works on a large number of devices, with a focus on recent Samsung, Apple, Huawei and Sony ones.

  • BT Mobile

BT Mobile offers 4G Calling in the same places as EE, so again, it’s widely available, and it works with any iPhone from the iPhone 6 onwards, as well as a number of Android phones.

  • Sky Mobile

Sky Mobile uses O2’s network for VoLTE (and everything else). However its VoLTE is very limited, as at the time of writing Sky claims it only works on the Samsung Galaxy S9 and Samsung Galaxy S9 Plus.

How do I know if my phone supports VoLTE?

If you’re using a 3G handset then you’ll definitely need to upgrade, but if you have a 4G enabled one (which most modern smartphones are) then it might work with VoLTE (though it may require a software update first).

In theory most existing 4G phones should work with VoLTE, but some may encounter problems and as they all require a tailored software update it’s dependent on each network to roll one out, so if you don’t have a new and popular phone then you may be left waiting indefinitely. In practice, each network only currently supports VoLTE on a subset of phones, and in some cases only those bought directly from the network.

Check the lists and links above for the full range of phones that are currently VoLTE-compatible on each network.

Why haven't we been making calls over 4G with VoLTE all along?

The problem with Voice over LTE is that 4G LTE is a data-only networking technology, so it doesn’t natively support voice calls. While 3G and 2G were primarily designed with voice calls in mind and data was added to them.

As such it’s been necessary to create new protocols to support voice calling over 4G and it’s a big job, requiring upgrades across the entire voice call infrastructure. There’s no one standard for this, with different networks creating their own solutions.

There are some common problems and solutions though, most notably the requirement for Single Radio Voice Call Continuity (SRVCC), which simply means that the phone will be able to switch back to a 2G or 3G signal if you move out of a 4G signal zone during the call.

This needs to be seamless or the call will cut out, so it requires masts to pre-emptively deliver a 3G signal whenever the 4G signal drops dangerously low, but also to keep the 4G signal running at the same time, so it can either stay on 3G if it loses the 4G signal entirely or drop the 3G if the 4G signal becomes strengthened again.

What about 5G Calling?

At the time of writing, 5G isn’t used for calls, just as 4G didn’t used to be (and still isn’t in some cases).

We’d imagine that eventually call support will be added to the UK’s 5G networks, especially as it is a use case that has been explored during the development of 5G, but there’s no current indication of when that will happen – right now the focus of networks is understandably on increasing 5G coverage.

Latest Offers

Sim Deals

SIM Card Triple SIM
2 GB Data 1000 Minutes 1000 Texts £5.00 a month
100 International Mins
View Details
SIM Card Triple SIM
3 GB Data UNLIMITED Minutes UNLIMITED Texts £6.00 a month View Details
View More

Latest Phones

Compare phone deals and save
Sign up for our newsletter.