Modern mobile device operating conditions often dictate their own rules, especially when it comes to voice quality. In densely populated cities, office buildings, or, conversely, in remote country homes, cellular network signal can be unstable or completely absent. It's in these situations that technology comes to the rescue. Voice over Wi-Fi, allowing you to make regular phone calls using your home or office wireless internet network. MTS is actively implementing this feature, ensuring subscribers have uninterrupted communication even in coverage dead zones.
Activating this service does not require complex equipment or special plans, but the setup process may vary depending on your smartphone model and operating system version. VoWiFi Voice over Wi-Fi (Voice over Wi-Fi) is a standard that transmits voice traffic over IP protocols, providing high-quality audio (HD Voice) and battery savings compared to third-party messaging apps. In this article, we'll cover how to properly set up Wi-Fi calling on MTS, the device requirements, and how to troubleshoot common connection issues.
VoWiFi Technology: How It Works and Its Benefits
Technology Voice over Wi-Fi is an elegant solution to the problem of cellular network blind spots. Unlike popular apps like WhatsApp or Telegram, which require separate software installation and a contact in your friend list, Wi-Fi calls on MTS work within the system's phone book. To the other end, your call appears as a regular incoming call from your number, not an internet call. This is achieved by creating a secure tunnel between your device and the operator's servers.
Using this feature offers a number of undeniable benefits to the user. Firstly, it's a stable connection: if you have internet access, you can receive and make calls even in a basement or deep bunker where base station signals don't reach. Secondly, the sound quality often surpasses standard GSM calls thanks to support for high-resolution codecs. Finally, VoWiFi It allows you to save battery power because your smartphone doesn't need to constantly search for a cellular network if it's connected to a stable Wi-Fi hotspot.
⚠️ Please note: Call quality directly depends on the speed and stability of your internet connection. If your home network is overloaded (for example, when downloading large files or watching 4K videos with other users), delays or interruptions in connection may occur.
Checking device and SIM card compatibility
Before proceeding with the settings, you need to make sure that your equipment supports the technology. VoWiFiMTS supports a wide range of modern smartphones, but older models may not have the required software. Furthermore, it's important to ensure this feature is supported by the firmware version of the specific region in which the device was manufactured. If you purchased a phone intended for another market, this feature may not be available without a firmware update.
The SIM card itself is also critical. Outdated Mini-SIM cards or older Micro-SIM versions may not support the necessary authorization protocols for internet voice calls. In most cases, replacing the SIM card with a newer format is required. Nano-SIM with 4G/LTE support. This can be done free of charge at any MTS store upon presentation of your passport.
To check your smartphone's compatibility, please refer to the official documentation or the manufacturer's website. Below is a table of popular brands and series that are guaranteed to support VoWiFi with MTS when configured accordingly:
| Brand | Device series | Minimum OS version | Peculiarities |
|---|---|---|---|
| Apple | iPhone 6 and newer | iOS 13.0+ | Operator profile update required |
| Samsung | Galaxy S, A, Note (since 2016) | Android 8.0+ | You may need to change the firmware region. |
| Xiaomi | Mi, Redmi, POCO | Android 9.0+ | Manual activation in the engineering menu is often required. |
| Huawei | P, Mate, Nova | Android 9.0+ | Support depends on the region of release |
What to do if your phone is not on the list?
If your phone isn't listed, it doesn't mean it's 100% impossible to set up. Some devices support the technology at the hardware level, but it's hidden in the software. Try entering the code ##4636## in the dialer (it works on many Android devices), select "Phone Information," and look for the "Wi-Fi Calling Provisioning" toggle. If it's there, enable it.
Activation of the service on the operator's side
The first step in the setup process is activating the service on your number. MTS offers this feature free of charge for most tariff plans, but it may be disabled by default. There are several ways to activate the service, so choose the one that's most convenient for you. This step must be completed before setting up your phone; otherwise, the device will not be able to register with the VoWiFi network.
The fastest way is to use a USSD command. Open the Phone app and dial the short code. *115#After pressing the call button, you will receive an SMS notification confirming successful service activation. Alternatively, you can use your personal account in the My MTS mobile app or on the official website. In the "Services" section, find the "Communications" category and enable the "Wi-Fi Calling" option.
- 📱 Via USSD: dial
*115#and follow the instructions on the screen. - 💻 Personal account: Log in to your profile on the mts.ru website and go to the service management section.
- 📲 Application: Open "My MTS", select your number and find the service switch.
- 📞 Support: Call 0890 or 8 800 250 0890 from any phone.
⚠️ Note: After activating the service with your carrier, changes may take anywhere from a few seconds to 24 hours to take effect. If the phone settings don't immediately help, try restarting your device or turning on airplane mode for 10-15 seconds.
Setting up VoWiFi on Android smartphones
The Android operating system interface can vary significantly depending on the manufacturer (Samsung One UI, Xiaomi MIUI, Huawei EMUI, etc.), so the location of settings may vary. However, the general procedure remains the same. Find the section responsible for mobile network or connections and turn on the corresponding toggle switch.
On a standard version of Android (e.g. Google Pixel, Nokia, Motorola smartphones) the path usually looks like this: go to Settings → Network & Internet → Mobile Network → Wi-Fi CallingHere, you need to toggle the switch to the active position. In some cases, you may need to select your preferred connection type: "Wi-Fi only" or "Mobile network preferred." For stable operation, we recommend leaving the default settings.
☑️ Android Setup Checklist
On Samsung devices, the algorithm may differ slightly. Open Settings → Connections → Mobile networkFind "Wi-Fi Calling" and enable it. If you don't see this option, your model or firmware may not support the feature for the Russian region. In this case, you can try changing the phone's region (CSC) using special utilities, but this requires technical knowledge and carries risks.
Instructions for iPhone (iOS) owners
Apple smartphone owners are more fortunate: setting up Wi-Fi calling on MTS in the iOS ecosystem is usually automatic and requires minimal user intervention. The main requirement is the latest version of the operating system and updated carrier settings. Once you activate the service on MTS, your iPhone should automatically retrieve the profile and enable the required feature.
For manual verification or activation, please go to Settings → CellularIf you have two SIM cards, select the one from MTS. Find "Wi-Fi Calling" and make sure the switch is green. You can also enable "Add Wi-Fi Calling to other devices" here, which will allow you to receive calls on your iPad or Mac even if your iPhone is in another room.
If the Wi-Fi Calling option is missing or grayed out, follow these steps:
- 🔄 Update iOS to the latest available version via
Settings → General → Software Update. - 📡 Check for carrier settings updates:
Settings → General → About(A pop-up window will appear if an update is available). - 🗑 Delete your carrier profile (if you're having problems):
Settings → General → About(scroll down to "Operator Profile" and click "Update" or delete the old profile).
Diagnostics and solution
Even with proper setup, users may encounter issues: the VoWiFi icon doesn't appear, calls are dropped, or the connection quality is poor. One common cause is a conflict between network modes. If the phone is stuck in 3G or 2G mode, VoWiFi may not activate. Make sure the correct network type is selected in the mobile network settings. 4G/LTE or "Auto".
Another common issue is roaming. Some smartphone models require "Data Roaming" to be enabled in the settings, even if you're on your home network, since the call is technically routed through a third-party gateway. It's also worth checking whether your router is blocking ports required for SIP protocols (although MTS uses standard ports, corporate firewalls may block them).
If all else fails, try a full network reset. This will reset all Wi-Fi, Bluetooth, and mobile settings to factory defaults, but will not delete your personal data (photos, contacts). Here's how to reset: Settings → System → Reset → Reset network settings (on Android) or Settings → General → Transfer or reset iPhone → Reset → Reset Network Settings (on iOS).
⚠️ Please note: Menu interfaces and item names may change with the release of new operating system versions and updates to MTS tariff terms. If you don't see the described items, check the operator's official help page for the latest information or contact technical support.
Frequently Asked Questions (FAQ)
Is there an extra charge for Wi-Fi calls?
No, VoWiFi technology is not a separate paid service. Call minutes are charged according to your main MTS plan, just like regular voice calls. Internet traffic is also not consumed, as the Wi-Fi channel is used.
Is it possible to make calls via Wi-Fi if the SIM card has no network coverage at all?
Yes, this is the main advantage of this technology. If your smartphone displays the Wi-Fi icon and the "Wi-Fi Only" (or similar) status, you can make and receive calls even in Airplane Mode (with Wi-Fi enabled), when there's no cellular network coverage.
Why did the VoWiFi icon disappear during a call?
This may mean the phone has switched to the cellular network due to a deteriorating Wi-Fi signal or to ensure a stable connection (handover). The icon may also disappear if you're out of range of your home network.
Does this feature work abroad?
Yes, while roaming internationally, you can connect to local Wi-Fi and call Russian numbers at your home region's rates, avoiding roaming charges. However, to register for the VoWiFi network, your phone still needs to have at least a short signal from your home operator or have saved profiles.