IMPORTANT: This article applies only to specific products and/or operating systems. Check Applicable Products and Categories for details.
What is VoLTE?
VoLTE stands for Voice over Long-Term Evolution or Voice over LTE. VoLTE offers the possibility to voice call via the LTE/4G* mobile network.
Previously, 4G was limited to surfing the Internet. When it came to calls, your phone would automatically switch to 3G or 2G. You may recall a few seconds of delay before the recipient's phone rang. Thanks to VoLTE, that delay is gone.
On a 2G or 3G network, calls and data are separated and cannot work simultaneously. For example, during a phone call on a 2G network, any incoming text messages at that moment will only arrive after you’ve terminated your phone call. On a 4G LTE network, both calls and data work in unison, meaning that a text message will arrive instantly even during a call.
*The terms 4G and LTE refer to the same technology and can be used interchangeably.
- What do you need to make VoLTE calls?
- What are the benefits of VoLTE?
- Smooth transition between VoWiFi and VoLTE
- What is the difference between VoLTE and VoWiFi?
- Can I make emergency calls with VoLTE?
What do you need to make VoLTE calls?
To be able to make calls via the 4G/LTE network, some conditions must be fulfilled:
NOTE: Contact your network operator to verify what is valid for your Xperia device model.
- You must have an 4G/LTE-compatible phone.
- Your phone must be within the range of an 4G/LTE network.
- Your operator and subscription (incl. SIM card) must support VoLTE for the device model you're using. Your device must be compatible and running the latest software.
- Your phone must be running unmodified software as provided by your operator and/or manufacturer.
- VoLTE must be activated in your device’s settings.
What are the benefits of VoLTE?
- Fast call set-up.
- High voice quality and reduced background noise.
- The phone remains in the 4G/LTE network during voice calls.
- You can use 4G/LTE data services, such as web surfing and tethering, while simultaneously making and receiving calls.
- When calling over LTE, you don't use extra data but call minutes. You pay for the voice call service, not the data you use.
Smooth transition between VoWiFi and VoLTE
If you leave the Wi-Fi range during a Wi-Fi call (VoWiFi), your smartphone will automatically switch to VoLTE (Voice over data) and the call will continue. However, this will only happen if 4G/LTE is selected as Network mode on your phone and if you’re within the range of a 4G/LTE network. This transition is not possible when calling over Wi-Fi with a separate app such as Skype, WhatsApp, etc.
If VoWiFi, also known as Wi-Fi calling, doesn’t have VoLTE to fall back to, VoWiFi will switch to 3G or 2G, if available. This will make the call drop.
To learn more about VoWiFi / Wi-Fi calling, visit: What is the difference between VoIP and VoWiFi?
What is the difference between VoLTE and VoWiFi?
VoLTE and VoWiFi both allow you to make voice calls over the Internet. What’s more, both technologies make calls through your phone’s calling application without the need for third-party apps. The main difference is that Wi-Fi Calling relies on a connection via Wi-Fi, and VoLTE relies on a data connection from your operator. If both VoWiFi and VoLTE are enabled, your phone will automatically decide which service is the most optimal to ensure the best call quality possible.
Can I make emergency calls with VoLTE?
In some countries, calling emergency numbers over VoLTE is not possible.
However, there is always a fallback option. If you try to make an emergency call over VoLTE and this option is not available, your device will automatically use the mobile network, if it is within the range of the mobile network.