The modern pace of life dictates its own conditions, and stable voice communication becomes critical, even when you are in a room with thick walls or in a remote area of the city. Technology Voice over Wi-Fi (VoWiFi) MTS's Wi-Fi solution allows you to make and receive calls using Wi-Fi instead of traditional cell towers. This solution is ideal for apartments with poor GSM/LTE signal but high-speed home internet, providing crystal-clear sound and a stable connection.
Activating this feature doesn't require installing third-party apps or complex programs, as the technology is built directly into the software of modern smartphones. All you need is a compatible device, the latest firmware version, and support from your data plan. In most cases, the setup process takes just a few minutes and doesn't require extensive technical knowledge, but there are some nuances to consider depending on the operating system.
In this article, we'll walk you through all the steps to connect to the service, check your equipment's compatibility, and address common errors that may arise during setup. You'll learn how to properly configure your router and phone to make calls through Wi-Fi Calling Work smoothly, and you'll understand how this technology differs from popular messengers like WhatsApp or Telegram.
What is VoWiFi technology and how does it work?
Technology VoWiFi VoWiFi is a method for transmitting voice calls over IP using a wireless LAN internet connection. Unlike instant messaging calls, which require a specific app and contacts to be loaded, VoWiFi is integrated into your smartphone's standard dialing interface. This means incoming calls appear as normal, with caller ID and full phonebook functionality.
The principle of operation is that voice traffic is encrypted and transmitted via a Wi-Fi access point to MTS servers, where it is converted into a regular telephone network signal. This process is completely transparent to the user. If you leave the Wi-Fi coverage area during a call and there is a strong cellular signal outside, modern smartphones can automatically switch the call to LTE/3G without disconnecting, if the technology is supported. Seamless Handover.
The main advantage is the connection quality in areas where the operator's radio signal can't penetrate dense building structures, but where a stable wired internet connection is available. Furthermore, Wi-Fi calls often provide better audio quality thanks to the use of high-resolution codecs, such as HD Voice, provided that the channel is not overloaded with other devices.
⚠️ Please note: A stable internet connection is critical for this technology to work. If your router loses connection to your provider or the speed drops below 50-100 kbps, call quality may deteriorate significantly, or the call may not connect at all.
It's important to understand that despite internet usage, traffic is consumed according to your MTS tariff plan and is not billed as internet traffic (unless otherwise specified in your tariff terms). The operator treats this call as a regular voice call, so the minutes are deducted from your plan's volume.
Checking smartphone and tariff compatibility
Before setting up, you need to ensure that your hardware and software support VoWiFi networks. Not all phone models, even those released in recent years, have this feature, as it requires certification from the carrier and device manufacturer. The list of supported devices is constantly expanding, but is based on specific models and operating system versions.
MTS supports this service on most modern smartphones running iOS and Android. However, if you have a device not purchased from official dealers in Russia (so-called "gray" shipments), functionality may be limited or require additional firmware modifications. It's also important to have 4G/LTE service activated on your SIM card, as VoWiFi often works in conjunction with 4G technology.
Here are the basic hardware and software requirements for stable operation:
- 📱 iPhone: iPhone 5c and later models running iOS 13.3 or later (some older models may have limitations).
- 🤖 Android: Samsung, Xiaomi, Huawei, Honor and other brands' VoWiFi-enabled devices released after 2016-2017.
- 📡 Router: Any device that supports Wi-Fi 802.11n/ac/ax standards and provides a stable communication channel.
- 💳 Rate: The current MTS tariff plan with voice call support (archived tariffs may require a transition to new conditions).
Pay special attention to the operating system version. Smartphone developers regularly add support for new operators and regions through software updates. If your phone was purchased several years ago, try checking for system updates in the settings. VoWiFi support for MTS was often added through such updates, even if the feature wasn't available initially.
Furthermore, the SIM card must be relatively new. If you're using a SIM card issued more than 10 years ago and haven't replaced it, it might be worth contacting a mobile phone store to replace it with a 4G/USIM-enabled card. Older cards may not work properly with modern voice traffic encryption protocols.
Activation of the service on the operator's side
Before setting up your phone, you need to ensure that the "Wi-Fi Calling" service is activated in your MTS subscriber profile. In some cases, this feature is enabled by default for all compatible plans, but in most cases, manual activation is required via your personal account or a USSD command. Without this step, your phone will not be able to register with the VoWiFi network, even if all device settings are correct.
The fastest way to activate is by using a USSD command. Dial the code on your phone. *111*1018# and press the call button. The system will automatically process the request and send an SMS notification confirming successful service activation. This method is universal and works on all devices, regardless of operating system.
Alternative ways to manage the service include using the "My MTS" mobile app or your personal account on the operator's website. In the app, go to the "Services" section and find the category related to communications or internet. There, you'll see a toggle for the "Wi-Fi Calling" service.
If you prefer the web interface, the algorithm of actions will be as follows:
- 🌐 Log in to your personal account on the official MTS website.
- 🔍 Go to the service management section or search for "Wi-Fi Calling".
- ✅ Click the "Connect" button and confirm the action with the code from the SMS.
After activating the service with your carrier, you may need to reboot your smartphone to update the network profiles. This is a standard procedure that allows the phone to receive the latest network settings and register with the VoWiFi domain.
☑️ Check before setting up your phone
Setting up Wi-Fi calling on Android
On Android devices, the setup process may vary slightly depending on the manufacturer and the version of the operating system (MIUI, OneUI, EMUI, etc.). However, the general steps remain the same for all compatible smartphones. The main task is to find the appropriate switch in the phone's settings menu.
First, make sure your smartphone is connected to a Wi-Fi network. Then, go to the device's main settings. This option is typically located under "Connections," "Network & Internet," or "SIM cards & mobile networks." You can search for "Wi-Fi" or "VoWiFi" in the settings search to quickly find the desired option.
Let's look at the sequence of actions for popular brands:
- 📱 Samsung: Settings → Connections → Wi-Fi Calling (switch to active position).
- 🌾 Xiaomi / Redmi: Settings → SIM cards and mobile networks → Select an MTS SIM card → Enable "Wi-Fi Calling".
- 🔵 Honor / Huawei: Settings → Wireless & networks → Mobile networks → Wi-Fi calling → Activate.
In some cases, especially on custom firmware or phones purchased abroad, the menu item may be hidden. If you're sure the technology is supported but can't find the settings, try entering the code in the dialer menu. ##869434## (does not work on all models) or reset the network settings to factory settings.
⚠️ Note: On dual-SIM phones, the setting must be configured separately for each SIM card. Make sure you activate the feature specifically for your MTS number if you use SIM cards from different carriers.
Once the feature is enabled, a special icon should appear in the status bar (top line of the screen) next to the Wi-Fi indicator or instead of the 4G/LTE icon. On different phones, it may look like a telephone handset with a Wi-Fi symbol or the words VoWiFi / Wi-Fi Call.
Instructions for iPhone (iOS) users
Apple smartphone owners are fortunate to have a unified settings interface, which is the same for all iPhone models, starting with the iPhone 5c. Enabling Wi-Fi calling on iOS is extremely simplified and takes just a few seconds if the service is already enabled with your carrier.
To set up, go to the "Settings" menu on your device. Find the "Cellular" section (or "Mobile Data" depending on your locale). If you have two SIM cards (a physical and an eSIM, or two physical ones on models for China/Hong Kong), select the one belonging to MTS.
Next, tap "Wi-Fi Calling." Slide the switch to "On." The system may ask you to confirm your address for emergency services (E911). In Russia, this feature has limitations, and you can enter an approximate address or leave it as is, as dispatch services in the Russian Federation do not always correctly process geolocation for internet calls.
After turning it on, the following message will appear in the notification shade (where the time and battery charge are) MTS Wi-Fi or simply Wi-Fi next to the carrier's name. This means the phone is ready to make and receive calls over the wireless network.
If you don't see Wi-Fi Calling, check the following:
- 🔄 Make sure you have the latest version of iOS installed (Settings → General → Software Update).
- 📶 Check that the MTS SIM card is selected as the primary voice card in the "Cellular Settings" section.
- 📲 Try removing and reinserting the SIM card, after turning off the phone.
What should I do if the Wi-Fi Call icon disappears after updating iOS?
Sometimes after major iOS updates, network settings may reset or conflict with your carrier profile. In this case, go to Settings → General → Transfer or reset iPhone → Reset → Reset Network Settings. This won't delete your personal data, but it will return your network settings to factory defaults. You'll then need to re-enter your Wi-Fi password and enable the feature.
Comparing VoWiFi and messaging calls
Many users confuse VoWiFi technology with voice calls on WhatsApp, Viber, or Telegram. While both methods technically use an internet channel to transmit voice, the user experience and technical implementation are fundamentally different. Understanding these differences will help you choose the optimal communication method for different situations.
VoWiFi is a native phone feature. You don't need to open an app, wait for it to load, or check if the other person is online. You simply dial the number as usual. Furthermore, VoWiFi calls often have priority on the carrier's network, ensuring lower latency and a more stable connection compared to OTT (over-the-top) services that operate over the internet.
Below is a table comparing key features of the technologies:
| Characteristic | VoWiFi (MTS) | Messengers (WhatsApp, Viber) |
|---|---|---|
| Need for an application | Not required (built into the phone) | Installation and registration required |
| Tariffs | At the voice call rate (minutes) | Internet traffic consumption |
| Subscriber availability | Always available if the phone is on | Only if the subscriber has internet and the app |
| Caller ID | Full (CLIP/CLIR) | Only if the number is saved or in the profile |
Another important aspect is roaming. While abroad, you can connect to hotel Wi-Fi and call Russian numbers at the rates of your home region, just as if you were in Russia. You also don't pay roaming fees when using messaging apps, but you can't call regular landlines or mobile numbers (not messaging app subscribers) without purchasing additional credits.
Solution and troubleshooting
Despite the simplicity of setup, users may encounter various issues when using Wi-Fi calling. These are most often related to an unstable internet connection or conflicting router security settings. If the VoWiFi icon is lit, but calls aren't connecting, or the connection quality is poor, follow these steps.
First, check your internet speed. A stable connection of at least 100 kbps in both directions is required for a comfortable conversation. If you have many devices connected to your Wi-Fi network downloading files or watching 4K videos, the bandwidth may not be sufficient for the voice packet. Try pausing downloads on other devices.
The second common problem is blocked ports or protocols on the router. Some home internet providers or corporate networks may block SIP traffic or traffic specific to VoIP. On your home network, check your router settings: make sure UPnP or NAT Open/Moderate type. Strict NAT may prevent the connection from being established.
It's also worth keeping in mind that when calling emergency services (112, 102, 103), location information may be inaccurate. The operator sees the Wi-Fi hotspot address, which may differ from your actual location, especially if you're using a router registered at a different address or a mobile hotspot.
Why doesn't the VoWiFi icon appear after all the settings?
If you've completed all the steps and the icon still doesn't appear, your phone may not have fully registered with the IMS (IP Multimedia Subsystem) network. Try turning on airplane mode for 10 seconds, then turning it off. If that doesn't help, reboot your phone. In rare cases, you may need to reflash your phone or contact a service center to check the device's IMEI address against the supported database.
Do you charge for Wi-Fi calls when roaming?
Yes, calls are charged according to your plan. However, while roaming, you won't be charged roaming rates for incoming and outgoing calls to Russian numbers as long as you're within Wi-Fi coverage. Calls will be made as if they were from your home region. However, be careful: if the Wi-Fi signal drops during a call, your phone may switch to the local cellular network, at which point roaming rates will apply.
Is it possible to use VoWiFi without mobile internet?
Technically, VoWiFi only requires Wi-Fi. However, many Android smartphones require the "Mobile Data" slider to be turned on in the settings, even when connected to Wi-Fi. This is necessary for service data exchange with the carrier's network (IMS registration). On an iPhone, simply having a SIM card is sufficient; data can be turned off.
In conclusion, MTS's Wi-Fi calling technology is a powerful tool for improving connection quality. It requires minimal setup and offers significant benefits in areas with poor cellular coverage. Using the instructions provided, you can stay connected anywhere with Wi-Fi access.