VoLTE, or Voice over LTE, is how our phones and carriers transmit our voices during a call, and if you have a modern phone, you're probably already using it. All of the major U.S. carriers have rolled out the red carpet for VoLTE on LTE, or what most of us call 4G. VoLTE is now available in the vast majority of the country as carriers work to expand LTE and 5G coverage to all towers. If your phone is a few years old and you're not already using VoLTE, it's a good idea to switch over not only for higher quality, but to be ready to take advantage of all new towers being installed.
Let's take a deeper look.
What is VoLTE?
As the name suggests, Voice over LTE happens when your carrier allows you to place a phone call over your LTE connection instead of the older legacy voice networks. For example, Verizon Wireless used 1XRTT in years past for all voice calls, switching to LTE only for data usage like browsing the web. This used to be why Verizon phones couldn't simultaneously use voice and data. Likewise, AT&T and T-Mobile relied on a combination of LTE for data and HSPA+ for calls and would drop down to a 3G signal when talking to someone on the other line. With VoLTE, neither of these scenarios is necessary.
What both network types now have in common, thanks to VoLTE, is the ability to use more bandwidth to make phone calls with higher-quality audio traveling both ways. When you are on a call with someone else using VoLTE, you can immediately notice the difference in call quality on both ends. You might also notice calls connecting faster.
Which U.S. carriers support VoLTE?
However, some carriers refer to VoLTE as HD Voice for marketing reasons, as it points to its increased fidelity compared to a traditional cell call. At this point, most people making a call on a modern smartphone will be using HD Voice whether they know it or not. Most MVNOs and Prepaid carriers use VoLTE for the majority of calls and some, like Visible, even require it.
Wi-Fi calling tech is nearly identical to HD Voice from the user's perspective in that it uses a Wi-Fi data connection to complete the call instead of LTE data. On all carriers, you can expect an increase in quality as long as your connection is solid. This can be essential for people that work or live in the concrete brutalist buildings that were commonly built in the 70s and 80s that block outside cell signals.
Some prepaid carriers, such as Visible, have even already moved to an all-digital network, with VoLTE being the only option for calls.
How can I use VoLTE?
Every major carrier supports VoLTE, and pretty much any new phone you buy today supports it. In fact, it's probably enabled on your phone already.
On an iPhone, the setting is a toggle in the main settings under Cellular, then Cellular Data Options. (You might notice that when you change this selection, the network indicator on the phone resets.)
On most newer Samsung phones, the option will be in the connections category in the phone's settings. On other phones, such as those from OnePlus, it's very similar to the option under Wi-Fi & network category.
A few things need to go right for VoLTE to take effect, including having a good enough LTE connection on a tower that supports VoLTE. You'll also need a device that supports VoLTE. This is something that will need to be confirmed on each device on each carrier, but most phones released in the last couple of years should be onboard.
The eventual goal for carriers is to move everyone over to calling on VoIP, which stands for Voice over Internet Protocol. Once this happens, features like VoLTE, VoNR (5G), and Wi-Fi Calling will fall into the same category and allow calling when connected to any secure internet source. This includes standalone 5G, and as more efficient 5G networks mature, carriers are going to want customers to stay on that tower as much as possible.
What else do I need to know about VoLTE?
Today, all carriers count HD Voice/VoLTE calls toward the minutes in one's monthly bucket and not data, even though VoLTE uses the same data network as video streaming or browsing the web. But for carriers like Verizon that support video calls under the VoLTE standard, the voice portion of a chat will use minutes, while the video portion will use data. Verizon says that "an average 1-minute video call uses about 6-8 MB of data," so unless you're hanging on to an ancient small data plan, it's likely a nonissue.
It's also worth noting that all major carriers offer Wi-Fi calling, which routes regular voice calls through a Wi-Fi network in areas of poor cellular coverage or just to improve call quality and reliability. Wi-Fi calling has more hoops to jump through than VoLTE does on U.S. carriers — especially on AT&T — but it can be a very useful tool if you live near or in a dead zone.
It's also worth keeping in mind that VoLTE will likely not be available if you're traveling internationally. Wi-Fi calling should still be available.
While the VoLTE revolution has been slow and steady, it's mostly complete. It's good to see progress from mobile carriers, especially as spectrum becomes more valuable ahead of further 5G deployment.
Do I need to upgrade my phone to keep making calls?
Most people, even those still using older phones without VoLTE support, will upgrade voluntarily before any network requires them to do so. However, if you have an older phone without VoLTE support and are just looking for stronger and more consistent performance, especially while traveling, upgrading to one of the best Android phones with support for VoLTE is a good move.
If you bought a phone from a carrier, like AT&T, and tried to take it to another, like Verizon, there may be some incompatibility between software versions that makes VoLTE not work properly.
In 2020, some AT&T customers were told that they needed to upgrade their phones to continue using the service. In fact, AT&T has already shut down its 3G network so affected customers should have already been upgraded to LTE-compatible devices. T-Mobile also took its 3G network down in 2022, so customers more than likely have already been upgraded to VoLTE phones.
AT&T isn't the first carrier to drop support for older phones, and it certainly won't be the last. The fact of the matter is that maintaining equipment for all of its legacy networks for the few customers that insist on using dated phones is a huge waste. While using a phone for longer is good for the environment, there's a point where the hardware just can't keep up with modern infrastructure.
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When Samuel is not writing about networking or 5G at Android Central, he spends most of his time researching computer components and obsessing over what CPU goes into the ultimate Windows 98 computer. It's the Pentium 3.